* Re: [PATCH v4 04/23] LSM: Create and manage the lsmblob data structure.
From: John Johansen @ 2019-06-26 23:39 UTC (permalink / raw)
To: Casey Schaufler, casey.schaufler, jmorris, linux-security-module,
selinux
Cc: keescook, penguin-kernel, paul, sds
In-Reply-To: <20190626192234.11725-5-casey@schaufler-ca.com>
On 6/26/19 12:22 PM, Casey Schaufler wrote:
> When more than one security module is exporting data to
> audit and networking sub-systems a single 32 bit integer
> is no longer sufficient to represent the data. Add a
> structure to be used instead.
>
> The lsmblob structure is currently an array of
> u32 "secids". There is an entry for each of the
> security modules built into the system that would
> use secids if active. The system assigns the module
> a "slot" when it registers hooks. If modules are
> compiled in but not registered there will be unused
> slots.
>
> A new lsm_id structure, which contains the name
> of the LSM and its slot number, is created. There
> is an instance for each LSM, which assigns the name
> and passes it to the infrastructure to set the slot.
>
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
> ---
> include/linux/lsm_hooks.h | 12 +++++--
> include/linux/security.h | 66 ++++++++++++++++++++++++++++++++++++++
> security/apparmor/lsm.c | 4 ++-
> security/commoncap.c | 7 +++-
> security/loadpin/loadpin.c | 8 ++++-
> security/safesetid/lsm.c | 8 ++++-
> security/security.c | 31 ++++++++++++++----
> security/selinux/hooks.c | 5 ++-
> security/smack/smack_lsm.c | 4 ++-
> security/tomoyo/tomoyo.c | 8 ++++-
> security/yama/yama_lsm.c | 4 ++-
> 11 files changed, 140 insertions(+), 17 deletions(-)
>
> diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
> index 3fe39abccc8f..fe1fb7a69ee5 100644
> --- a/include/linux/lsm_hooks.h
> +++ b/include/linux/lsm_hooks.h
> @@ -2029,6 +2029,14 @@ struct security_hook_heads {
> #endif /* CONFIG_BPF_SYSCALL */
> } __randomize_layout;
>
> +/*
> + * Information that identifies a security module.
> + */
> +struct lsm_id {
> + const char *lsm; /* Name of the LSM */
> + int slot; /* Slot in lsmblob if one is allocated */
> +};
> +
> /*
> * Security module hook list structure.
> * For use with generic list macros for common operations.
> @@ -2037,7 +2045,7 @@ struct security_hook_list {
> struct hlist_node list;
> struct hlist_head *head;
> union security_list_options hook;
> - char *lsm;
> + struct lsm_id *lsmid;
> } __randomize_layout;
>
> /*
> @@ -2068,7 +2076,7 @@ extern struct security_hook_heads security_hook_heads;
> extern char *lsm_names;
>
> extern void security_add_hooks(struct security_hook_list *hooks, int count,
> - char *lsm);
> + struct lsm_id *lsmid);
>
> #define LSM_FLAG_LEGACY_MAJOR BIT(0)
> #define LSM_FLAG_EXCLUSIVE BIT(1)
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 49f2685324b0..5bb8b9a6fa84 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -76,6 +76,72 @@ enum lsm_event {
> LSM_POLICY_CHANGE,
> };
>
> +/*
> + * Data exported by the security modules
> + *
> + * Any LSM that provides secid or secctx based hooks must be included.
> + */
> +#define LSMBLOB_ENTRIES ( \
> + (IS_ENABLED(CONFIG_SECURITY_SELINUX) ? 1 : 0) + \
> + (IS_ENABLED(CONFIG_SECURITY_SMACK) ? 1 : 0) + \
> + (IS_ENABLED(CONFIG_SECURITY_APPARMOR) ? 1 : 0))
> +
> +struct lsmblob {
> + u32 secid[LSMBLOB_ENTRIES];
> +};
> +
> +#define LSMBLOB_INVALID -1 /* Not a valid LSM slot number */
> +#define LSMBLOB_NEEDED -2 /* Slot requested on initialization */
> +#define LSMBLOB_NOT_NEEDED -3 /* Slot not requested */
> +
> +/**
> + * lsmblob_init - initialize an lsmblob structure.
> + * @blob: Pointer to the data to initialize
> + * @secid: The initial secid value
> + *
> + * Set all secid for all modules to the specified value.
> + */
> +static inline void lsmblob_init(struct lsmblob *blob, u32 secid)
> +{
> + int i;
> +
> + for (i = 0; i < LSMBLOB_ENTRIES; i++)
> + blob->secid[i] = secid;
> +}
> +
> +/**
> + * lsmblob_is_set - report if there is an value in the lsmblob
> + * @blob: Pointer to the exported LSM data
> + *
> + * Returns true if there is a secid set, false otherwise
> + */
> +static inline bool lsmblob_is_set(struct lsmblob *blob)
> +{
> + int i;
> +
> + for (i = 0; i < LSMBLOB_ENTRIES; i++)
> + if (blob->secid[i] != 0)
> + return true;
> + return false;
> +}
> +
> +/**
> + * lsmblob_equal - report if the two lsmblob's are equal
> + * @bloba: Pointer to one LSM data
> + * @blobb: Pointer to the other LSM data
> + *
> + * Returns true if all entries in the two are equal, false otherwise
> + */
> +static inline bool lsmblob_equal(struct lsmblob *bloba, struct lsmblob *blobb)
> +{
> + int i;
> +
> + for (i = 0; i < LSMBLOB_ENTRIES; i++)
> + if (bloba->secid[i] != blobb->secid[i])
> + return false;
> + return true;
> +}
> +
> /* These functions are in security/commoncap.c */
> extern int cap_capable(const struct cred *cred, struct user_namespace *ns,
> int cap, unsigned int opts);
> diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
> index 2716e7731279..6d2eefc9b7c1 100644
> --- a/security/apparmor/lsm.c
> +++ b/security/apparmor/lsm.c
> @@ -1138,6 +1138,8 @@ struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = {
> .lbs_sock = sizeof(struct aa_sk_ctx),
> };
>
> +static struct lsm_id apparmor_lsmid = { .lsm="apparmor", .slot=LSMBLOB_NEEDED };
__lsm_ro_after_init
> +
> static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
> LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
> LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
> @@ -1679,7 +1681,7 @@ static int __init apparmor_init(void)
> goto buffers_out;
> }
> security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
> - "apparmor");
> + &apparmor_lsmid);
>
> /* Report that AppArmor successfully initialized */
> apparmor_initialized = 1;
> diff --git a/security/commoncap.c b/security/commoncap.c
> index afd9679ca866..305a6088c81e 100644
> --- a/security/commoncap.c
> +++ b/security/commoncap.c
> @@ -1344,6 +1344,11 @@ int cap_mmap_file(struct file *file, unsigned long reqprot,
>
> #ifdef CONFIG_SECURITY
>
> +static struct lsm_id capability_lsmid = {
__lsm_ro_after_init
> + .lsm="capability",
> + .slot=LSMBLOB_NOT_NEEDED
> +};
> +
> static struct security_hook_list capability_hooks[] __lsm_ro_after_init = {
> LSM_HOOK_INIT(capable, cap_capable),
> LSM_HOOK_INIT(settime, cap_settime),
> @@ -1368,7 +1373,7 @@ static struct security_hook_list capability_hooks[] __lsm_ro_after_init = {
> static int __init capability_init(void)
> {
> security_add_hooks(capability_hooks, ARRAY_SIZE(capability_hooks),
> - "capability");
> + &capability_lsmid);
> return 0;
> }
>
> diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c
> index 055fb0a64169..13db59d5327e 100644
> --- a/security/loadpin/loadpin.c
> +++ b/security/loadpin/loadpin.c
> @@ -181,6 +181,11 @@ static int loadpin_load_data(enum kernel_load_data_id id)
> return loadpin_read_file(NULL, (enum kernel_read_file_id) id);
> }
>
> +static struct lsm_id loadpin_lsmid = {
__lsm_ro_after_init
> + .lsm="loadpin",
> + .slot=LSMBLOB_NOT_NEEDED
> +};
> +
> static struct security_hook_list loadpin_hooks[] __lsm_ro_after_init = {
> LSM_HOOK_INIT(sb_free_security, loadpin_sb_free_security),
> LSM_HOOK_INIT(kernel_read_file, loadpin_read_file),
> @@ -191,7 +196,8 @@ static int __init loadpin_init(void)
> {
> pr_info("ready to pin (currently %senforcing)\n",
> enforce ? "" : "not ");
> - security_add_hooks(loadpin_hooks, ARRAY_SIZE(loadpin_hooks), "loadpin");
> + security_add_hooks(loadpin_hooks, ARRAY_SIZE(loadpin_hooks),
> + &loadpin_lsmid);
> return 0;
> }
>
> diff --git a/security/safesetid/lsm.c b/security/safesetid/lsm.c
> index cecd38e2ac80..ca34badde4cf 100644
> --- a/security/safesetid/lsm.c
> +++ b/security/safesetid/lsm.c
> @@ -255,6 +255,11 @@ void flush_safesetid_whitelist_entries(void)
> }
> }
>
> +static struct lsm_id safesetid_lsmid = {
__lsm_ro_after_init
> + .lsm="safesetid",
> + .slot=LSMBLOB_NOT_NEEDED
> +};
> +
> static struct security_hook_list safesetid_security_hooks[] = {
> LSM_HOOK_INIT(task_fix_setuid, safesetid_task_fix_setuid),
> LSM_HOOK_INIT(capable, safesetid_security_capable)
> @@ -263,7 +268,8 @@ static struct security_hook_list safesetid_security_hooks[] = {
> static int __init safesetid_security_init(void)
> {
> security_add_hooks(safesetid_security_hooks,
> - ARRAY_SIZE(safesetid_security_hooks), "safesetid");
> + ARRAY_SIZE(safesetid_security_hooks),
> + &safesetid_lsmid);
>
> /* Report that SafeSetID successfully initialized */
> safesetid_initialized = 1;
> diff --git a/security/security.c b/security/security.c
> index 7cfedb90210a..27e2db3d6b04 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -317,6 +317,7 @@ static void __init ordered_lsm_init(void)
> init_debug("sock blob size = %d\n", blob_sizes.lbs_sock);
> init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
> init_debug("task blob size = %d\n", blob_sizes.lbs_task);
> + init_debug("lsmblob size = %lu\n", sizeof(struct lsmblob));
>
> /*
> * Create any kmem_caches needed for blobs
> @@ -399,7 +400,7 @@ static bool match_last_lsm(const char *list, const char *lsm)
> return !strcmp(last, lsm);
> }
>
> -static int lsm_append(char *new, char **result)
> +static int lsm_append(const char *new, char **result)
> {
> char *cp;
>
> @@ -420,24 +421,40 @@ static int lsm_append(char *new, char **result)
> return 0;
> }
>
> +/*
> + * Current index to use while initializing the lsmblob secid list.
> + */
> +static int lsm_slot __initdata;
> +
> /**
> * security_add_hooks - Add a modules hooks to the hook lists.
> * @hooks: the hooks to add
> * @count: the number of hooks to add
> - * @lsm: the name of the security module
> + * @lsmid: the identification information for the security module
> *
> * Each LSM has to register its hooks with the infrastructure.
> + * If the LSM is using hooks that export secids allocate a slot
> + * for it in the lsmblob.
> */
> void __init security_add_hooks(struct security_hook_list *hooks, int count,
> - char *lsm)
> + struct lsm_id *lsmid)
> {
> int i;
>
> + if (lsmid->slot == LSMBLOB_NEEDED) {
> + if (lsm_slot >= LSMBLOB_ENTRIES)
> + panic("%s Too many LSMs registered.\n", __func__);
> + lsmid->slot = lsm_slot++;
> + init_debug("%s assigned lsmblob slot %d\n", lsmid->lsm,
> + lsmid->slot);
> + }
It might be nice (but not required) to add back in the list of hooks that need
secids as a cross check of LSMLOB_NOT_NEEDED. It would allow us to catch
bad registrations upfront instead of crashing the kernel when the hook gets
used.
> +
> for (i = 0; i < count; i++) {
> - hooks[i].lsm = lsm;
> + hooks[i].lsmid = lsmid;
> hlist_add_tail_rcu(&hooks[i].list, hooks[i].head);
> }
> - if (lsm_append(lsm, &lsm_names) < 0)
> +
> + if (lsm_append(lsmid->lsm, &lsm_names) < 0)
> panic("%s - Cannot get early memory.\n", __func__);
> }
>
> @@ -1917,7 +1934,7 @@ int security_getprocattr(struct task_struct *p, const char *lsm, char *name,
> struct security_hook_list *hp;
>
> hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) {
> - if (lsm != NULL && strcmp(lsm, hp->lsm))
> + if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm))
> continue;
> return hp->hook.getprocattr(p, name, value);
> }
> @@ -1930,7 +1947,7 @@ int security_setprocattr(const char *lsm, const char *name, void *value,
> struct security_hook_list *hp;
>
> hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) {
> - if (lsm != NULL && strcmp(lsm, hp->lsm))
> + if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm))
> continue;
> return hp->hook.setprocattr(name, value, size);
> }
> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> index c83ec2652eda..8c93b07bb353 100644
> --- a/security/selinux/hooks.c
> +++ b/security/selinux/hooks.c
> @@ -6622,6 +6622,8 @@ struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
> .lbs_superblock = sizeof(struct superblock_security_struct),
> };
>
> +static struct lsm_id selinux_lsmid = { .lsm="selinux", .slot=LSMBLOB_NEEDED };
> +
> static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
> LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
> LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
> @@ -6877,7 +6879,8 @@ static __init int selinux_init(void)
>
> hashtab_cache_init();
>
> - security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
> + security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
> + &selinux_lsmid);
>
> if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
> panic("SELinux: Unable to register AVC netcache callback\n");
> diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
> index e9560b078efe..ad646b865295 100644
> --- a/security/smack/smack_lsm.c
> +++ b/security/smack/smack_lsm.c
> @@ -4553,6 +4553,8 @@ struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = {
> .lbs_superblock = sizeof(struct superblock_smack),
> };
>
> +static struct lsm_id smack_lsmid = { .lsm="smack", .slot=LSMBLOB_NEEDED };
__lsm_ro_after_init
> +
> static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
> LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
> LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
> @@ -4743,7 +4745,7 @@ static __init int smack_init(void)
> /*
> * Register with LSM
> */
> - security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack");
> + security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), &smack_lsmid);
> smack_enabled = 1;
>
> pr_info("Smack: Initializing.\n");
> diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c
> index 716c92ec941a..57e6b845ea51 100644
> --- a/security/tomoyo/tomoyo.c
> +++ b/security/tomoyo/tomoyo.c
> @@ -529,6 +529,11 @@ static void tomoyo_task_free(struct task_struct *task)
> }
> }
>
> +static struct lsm_id tomoyo_lsmid = {
__lsm_ro_after_init
> + .lsm="tomoyo",
> + .slot=LSMBLOB_NOT_NEEDED
> +};
> +
> /*
> * tomoyo_security_ops is a "struct security_operations" which is used for
> * registering TOMOYO.
> @@ -581,7 +586,8 @@ static int __init tomoyo_init(void)
> struct tomoyo_task *s = tomoyo_task(current);
>
> /* register ourselves with the security framework */
> - security_add_hooks(tomoyo_hooks, ARRAY_SIZE(tomoyo_hooks), "tomoyo");
> + security_add_hooks(tomoyo_hooks, ARRAY_SIZE(tomoyo_hooks),
> + &tomoyo_lsmid);
> pr_info("TOMOYO Linux initialized\n");
> s->domain_info = &tomoyo_kernel_domain;
> atomic_inc(&tomoyo_kernel_domain.users);
> diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c
> index efac68556b45..2263822a4af7 100644
> --- a/security/yama/yama_lsm.c
> +++ b/security/yama/yama_lsm.c
> @@ -425,6 +425,8 @@ static int yama_ptrace_traceme(struct task_struct *parent)
> return rc;
> }
>
> +static struct lsm_id yama_lsmid = { .lsm="yama", .slot=LSMBLOB_NOT_NEEDED };
__lsm_ro_after_init
> +
> static struct security_hook_list yama_hooks[] __lsm_ro_after_init = {
> LSM_HOOK_INIT(ptrace_access_check, yama_ptrace_access_check),
> LSM_HOOK_INIT(ptrace_traceme, yama_ptrace_traceme),
> @@ -482,7 +484,7 @@ static inline void yama_init_sysctl(void) { }
> static int __init yama_init(void)
> {
> pr_info("Yama: becoming mindful.\n");
> - security_add_hooks(yama_hooks, ARRAY_SIZE(yama_hooks), "yama");
> + security_add_hooks(yama_hooks, ARRAY_SIZE(yama_hooks), &yama_lsmid);
> yama_init_sysctl();
> return 0;
> }
>
I like the change,
Reviewed-by: John Johansen <john.johansen@canonical.com>
^ permalink raw reply
* Re: [PATCH v4 05/23] LSM: Use lsmblob in security_audit_rule_match
From: John Johansen @ 2019-06-26 23:45 UTC (permalink / raw)
To: Casey Schaufler, casey.schaufler, jmorris, linux-security-module,
selinux
Cc: keescook, penguin-kernel, paul, sds
In-Reply-To: <20190626192234.11725-6-casey@schaufler-ca.com>
On 6/26/19 12:22 PM, Casey Schaufler wrote:
> Change the secid parameter of security_audit_rule_match
> to a lsmblob structure pointer. Pass the entry from the
> lsmblob structure for the approprite slot to the LSM hook.
>
> Change the users of security_audit_rule_match to use the
> lsmblob instead of a u32. In some cases this requires a
> temporary conversion using lsmblob_init() that will go
> away when other interfaces get converted.
>
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
> ---
> include/linux/security.h | 7 ++++---
> kernel/auditfilter.c | 7 +++++--
> kernel/auditsc.c | 14 ++++++++++----
> security/integrity/ima/ima.h | 4 ++--
> security/integrity/ima/ima_policy.c | 7 +++++--
> security/security.c | 18 +++++++++++++++---
> 6 files changed, 41 insertions(+), 16 deletions(-)
>
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 5bb8b9a6fa84..4f8b478bc3a1 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -1761,7 +1761,8 @@ static inline int security_key_getsecurity(struct key *key, char **_buffer)
> #ifdef CONFIG_SECURITY
> int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule);
> int security_audit_rule_known(struct audit_krule *krule);
> -int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule);
> +int security_audit_rule_match(struct lsmblob *blob, u32 field, u32 op,
> + void *lsmrule);
> void security_audit_rule_free(void *lsmrule);
>
> #else
> @@ -1777,8 +1778,8 @@ static inline int security_audit_rule_known(struct audit_krule *krule)
> return 0;
> }
>
> -static inline int security_audit_rule_match(u32 secid, u32 field, u32 op,
> - void *lsmrule)
> +static inline int security_audit_rule_match(struct lsmblob *blob, u32 field,
> + u32 op, void *lsmrule)
> {
> return 0;
> }
> diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
> index 63f8b3f26fab..8786b95b60bd 100644
> --- a/kernel/auditfilter.c
> +++ b/kernel/auditfilter.c
> @@ -1324,6 +1324,7 @@ int audit_filter(int msgtype, unsigned int listtype)
> struct audit_field *f = &e->rule.fields[i];
> pid_t pid;
> u32 sid;
> + struct lsmblob blob;
>
> switch (f->type) {
> case AUDIT_PID:
> @@ -1354,8 +1355,10 @@ int audit_filter(int msgtype, unsigned int listtype)
> case AUDIT_SUBJ_CLR:
> if (f->lsm_rule) {
> security_task_getsecid(current, &sid);
> - result = security_audit_rule_match(sid,
> - f->type, f->op, f->lsm_rule);
> + lsmblob_init(&blob, sid);
> + result = security_audit_rule_match(
> + &blob, f->type,
> + f->op, f->lsm_rule);
> }
> break;
> case AUDIT_EXE:
> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index d1eab1d4a930..18ee5556c086 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -445,6 +445,7 @@ static int audit_filter_rules(struct task_struct *tsk,
> const struct cred *cred;
> int i, need_sid = 1;
> u32 sid;
> + struct lsmblob blob;
> unsigned int sessionid;
>
> cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);
> @@ -630,7 +631,9 @@ static int audit_filter_rules(struct task_struct *tsk,
> security_task_getsecid(tsk, &sid);
> need_sid = 0;
> }
> - result = security_audit_rule_match(sid, f->type,
> + lsmblob_init(&blob, sid);
> + result = security_audit_rule_match(&blob,
> + f->type,
> f->op,
> f->lsm_rule);
> }
> @@ -645,15 +648,17 @@ static int audit_filter_rules(struct task_struct *tsk,
> if (f->lsm_rule) {
> /* Find files that match */
> if (name) {
> + lsmblob_init(&blob, name->osid);
> result = security_audit_rule_match(
> - name->osid,
> + &blob,
> f->type,
> f->op,
> f->lsm_rule);
> } else if (ctx) {
> list_for_each_entry(n, &ctx->names_list, list) {
> + lsmblob_init(&blob, n->osid);
> if (security_audit_rule_match(
> - n->osid,
> + &blob,
> f->type,
> f->op,
> f->lsm_rule)) {
> @@ -665,7 +670,8 @@ static int audit_filter_rules(struct task_struct *tsk,
> /* Find ipc objects that match */
> if (!ctx || ctx->type != AUDIT_IPC)
> break;
> - if (security_audit_rule_match(ctx->ipc.osid,
> + lsmblob_init(&blob, ctx->ipc.osid);
> + if (security_audit_rule_match(&blob,
> f->type, f->op,
> f->lsm_rule))
> ++result;
> diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
> index d213e835c498..5a337239d9e4 100644
> --- a/security/integrity/ima/ima.h
> +++ b/security/integrity/ima/ima.h
> @@ -307,8 +307,8 @@ static inline int security_filter_rule_init(u32 field, u32 op, char *rulestr,
> return -EINVAL;
> }
>
> -static inline int security_filter_rule_match(u32 secid, u32 field, u32 op,
> - void *lsmrule)
> +static inline int security_filter_rule_match(struct lsmblob *blob, u32 field,
> + u32 op, void *lsmrule)
> {
> return -EINVAL;
> }
> diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
> index e0cc323f948f..e7b8ce942950 100644
> --- a/security/integrity/ima/ima_policy.c
> +++ b/security/integrity/ima/ima_policy.c
> @@ -327,6 +327,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
> for (i = 0; i < MAX_LSM_RULES; i++) {
> int rc = 0;
> u32 osid;
> + struct lsmblob blob;
> int retried = 0;
>
> if (!rule->lsm[i].rule)
> @@ -337,7 +338,8 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
> case LSM_OBJ_ROLE:
> case LSM_OBJ_TYPE:
> security_inode_getsecid(inode, &osid);
> - rc = security_filter_rule_match(osid,
> + lsmblob_init(&blob, osid);
> + rc = security_filter_rule_match(&blob,
> rule->lsm[i].type,
> Audit_equal,
> rule->lsm[i].rule);
> @@ -345,7 +347,8 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
> case LSM_SUBJ_USER:
> case LSM_SUBJ_ROLE:
> case LSM_SUBJ_TYPE:
> - rc = security_filter_rule_match(secid,
> + lsmblob_init(&blob, secid);
> + rc = security_filter_rule_match(&blob,
> rule->lsm[i].type,
> Audit_equal,
> rule->lsm[i].rule);
> diff --git a/security/security.c b/security/security.c
> index 27e2db3d6b04..46ca4b85ad96 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -424,7 +424,7 @@ static int lsm_append(const char *new, char **result)
> /*
> * Current index to use while initializing the lsmblob secid list.
> */
> -static int lsm_slot __initdata;
> +static int lsm_slot;
>
> /**
> * security_add_hooks - Add a modules hooks to the hook lists.
> @@ -2433,9 +2433,21 @@ void security_audit_rule_free(void *lsmrule)
> call_void_hook(audit_rule_free, lsmrule);
> }
>
> -int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule)
> +int security_audit_rule_match(struct lsmblob *blob, u32 field, u32 op,
> + void *lsmrule)
> {
> - return call_int_hook(audit_rule_match, 0, secid, field, op, lsmrule);
> + struct security_hook_list *hp;
> + int rc;
> +
> + hlist_for_each_entry(hp, &security_hook_heads.audit_rule_match, list) {
> + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
> + continue;
> + rc = hp->hook.audit_rule_match(blob->secid[hp->lsmid->slot],
> + field, op, lsmrule);
> + if (rc != 0)
> + return rc;
> + }
> + return 0;
> }
> #endif /* CONFIG_AUDIT */
>
>
^ permalink raw reply
* Re: [PATCH v4 06/23] LSM: Use lsmblob in security_kernel_act_as
From: John Johansen @ 2019-06-26 23:47 UTC (permalink / raw)
To: Casey Schaufler, casey.schaufler, jmorris, linux-security-module,
selinux
Cc: keescook, penguin-kernel, paul, sds
In-Reply-To: <20190626192234.11725-7-casey@schaufler-ca.com>
On 6/26/19 12:22 PM, Casey Schaufler wrote:
> Change the security_kernel_act_as interface to use a lsmblob
> structure in place of the single u32 secid in support of
> module stacking. Change it's only caller, set_security_override,
> to do the same. Change that one's only caller,
> set_security_override_from_ctx, to call it with the new
> parameter type.
>
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
> ---
> include/linux/cred.h | 3 ++-
> include/linux/security.h | 5 +++--
> kernel/cred.c | 10 ++++++----
> security/security.c | 14 ++++++++++++--
> 4 files changed, 23 insertions(+), 9 deletions(-)
>
> diff --git a/include/linux/cred.h b/include/linux/cred.h
> index efb6edf32de7..9a21c376ed97 100644
> --- a/include/linux/cred.h
> +++ b/include/linux/cred.h
> @@ -22,6 +22,7 @@
>
> struct cred;
> struct inode;
> +struct lsmblob;
>
> /*
> * COW Supplementary groups list
> @@ -165,7 +166,7 @@ extern const struct cred *override_creds(const struct cred *);
> extern void revert_creds(const struct cred *);
> extern struct cred *prepare_kernel_cred(struct task_struct *);
> extern int change_create_files_as(struct cred *, struct inode *);
> -extern int set_security_override(struct cred *, u32);
> +extern int set_security_override(struct cred *, struct lsmblob *);
> extern int set_security_override_from_ctx(struct cred *, const char *);
> extern int set_create_files_as(struct cred *, struct inode *);
> extern int cred_fscmp(const struct cred *, const struct cred *);
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 4f8b478bc3a1..313e45a3cac3 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -388,7 +388,7 @@ void security_cred_free(struct cred *cred);
> int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp);
> void security_transfer_creds(struct cred *new, const struct cred *old);
> void security_cred_getsecid(const struct cred *c, u32 *secid);
> -int security_kernel_act_as(struct cred *new, u32 secid);
> +int security_kernel_act_as(struct cred *new, struct lsmblob *blob);
> int security_kernel_create_files_as(struct cred *new, struct inode *inode);
> int security_kernel_module_request(char *kmod_name);
> int security_kernel_load_data(enum kernel_load_data_id id);
> @@ -971,7 +971,8 @@ static inline void security_transfer_creds(struct cred *new,
> {
> }
>
> -static inline int security_kernel_act_as(struct cred *cred, u32 secid)
> +static inline int security_kernel_act_as(struct cred *cred,
> + struct lsmblob *blob)
> {
> return 0;
> }
> diff --git a/kernel/cred.c b/kernel/cred.c
> index 45d77284aed0..71c14dda107e 100644
> --- a/kernel/cred.c
> +++ b/kernel/cred.c
> @@ -701,14 +701,14 @@ EXPORT_SYMBOL(prepare_kernel_cred);
> /**
> * set_security_override - Set the security ID in a set of credentials
> * @new: The credentials to alter
> - * @secid: The LSM security ID to set
> + * @blob: The LSM security information to set
> *
> * Set the LSM security ID in a set of credentials so that the subjective
> * security is overridden when an alternative set of credentials is used.
> */
> -int set_security_override(struct cred *new, u32 secid)
> +int set_security_override(struct cred *new, struct lsmblob *blob)
> {
> - return security_kernel_act_as(new, secid);
> + return security_kernel_act_as(new, blob);
> }
> EXPORT_SYMBOL(set_security_override);
>
> @@ -724,6 +724,7 @@ EXPORT_SYMBOL(set_security_override);
> */
> int set_security_override_from_ctx(struct cred *new, const char *secctx)
> {
> + struct lsmblob blob;
> u32 secid;
> int ret;
>
> @@ -731,7 +732,8 @@ int set_security_override_from_ctx(struct cred *new, const char *secctx)
> if (ret < 0)
> return ret;
>
> - return set_security_override(new, secid);
> + lsmblob_init(&blob, secid);
> + return set_security_override(new, &blob);
> }
> EXPORT_SYMBOL(set_security_override_from_ctx);
>
> diff --git a/security/security.c b/security/security.c
> index 46ca4b85ad96..f9c8e1926a0b 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -1627,9 +1627,19 @@ void security_cred_getsecid(const struct cred *c, u32 *secid)
> }
> EXPORT_SYMBOL(security_cred_getsecid);
>
> -int security_kernel_act_as(struct cred *new, u32 secid)
> +int security_kernel_act_as(struct cred *new, struct lsmblob *blob)
> {
> - return call_int_hook(kernel_act_as, 0, new, secid);
> + struct security_hook_list *hp;
> + int rc;
> +
> + hlist_for_each_entry(hp, &security_hook_heads.kernel_act_as, list) {
> + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
> + continue;
> + rc = hp->hook.kernel_act_as(new, blob->secid[hp->lsmid->slot]);
> + if (rc != 0)
> + return rc;
> + }
> + return 0;
> }
>
> int security_kernel_create_files_as(struct cred *new, struct inode *inode)
>
^ permalink raw reply
* Re: [PATCH v4 07/23] net: Prepare UDS for secuirty module stacking
From: John Johansen @ 2019-06-26 23:48 UTC (permalink / raw)
To: Casey Schaufler, casey.schaufler, jmorris, linux-security-module,
selinux
Cc: keescook, penguin-kernel, paul, sds
In-Reply-To: <20190626192234.11725-8-casey@schaufler-ca.com>
On 6/26/19 12:22 PM, Casey Schaufler wrote:
> Change the data used in UDS SO_PEERSEC processing from a
> secid to a more general struct lsmblob. Update the
> security_socket_getpeersec_dgram() interface to use the
> lsmblob. There is a small amount of scaffolding code
> that will come out when the security_secid_to_secctx()
> code is brought in line with the lsmblob.
>
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
> ---
> include/linux/security.h | 7 +++++--
> include/net/af_unix.h | 2 +-
> include/net/scm.h | 8 +++++---
> net/ipv4/ip_sockglue.c | 8 +++++---
> net/unix/af_unix.c | 6 +++---
> security/security.c | 18 +++++++++++++++---
> 6 files changed, 34 insertions(+), 15 deletions(-)
>
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 313e45a3cac3..dcf20da87d1b 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -1280,7 +1280,8 @@ int security_socket_shutdown(struct socket *sock, int how);
> int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb);
> int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
> int __user *optlen, unsigned len);
> -int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid);
> +int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
> + struct lsmblob *blob);
> int security_sk_alloc(struct sock *sk, int family, gfp_t priority);
> void security_sk_free(struct sock *sk);
> void security_sk_clone(const struct sock *sk, struct sock *newsk);
> @@ -1418,7 +1419,9 @@ static inline int security_socket_getpeersec_stream(struct socket *sock, char __
> return -ENOPROTOOPT;
> }
>
> -static inline int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
> +static inline int security_socket_getpeersec_dgram(struct socket *sock,
> + struct sk_buff *skb,
> + struct lsmblob *blob)
> {
> return -ENOPROTOOPT;
> }
> diff --git a/include/net/af_unix.h b/include/net/af_unix.h
> index 3426d6dacc45..933492c08b8c 100644
> --- a/include/net/af_unix.h
> +++ b/include/net/af_unix.h
> @@ -36,7 +36,7 @@ struct unix_skb_parms {
> kgid_t gid;
> struct scm_fp_list *fp; /* Passed files */
> #ifdef CONFIG_SECURITY_NETWORK
> - u32 secid; /* Security ID */
> + struct lsmblob lsmblob; /* Security LSM data */
> #endif
> u32 consumed;
> } __randomize_layout;
> diff --git a/include/net/scm.h b/include/net/scm.h
> index 1ce365f4c256..e2e71c4bf9d0 100644
> --- a/include/net/scm.h
> +++ b/include/net/scm.h
> @@ -33,7 +33,7 @@ struct scm_cookie {
> struct scm_fp_list *fp; /* Passed files */
> struct scm_creds creds; /* Skb credentials */
> #ifdef CONFIG_SECURITY_NETWORK
> - u32 secid; /* Passed security ID */
> + struct lsmblob lsmblob; /* Passed LSM data */
> #endif
> };
>
> @@ -46,7 +46,7 @@ struct scm_fp_list *scm_fp_dup(struct scm_fp_list *fpl);
> #ifdef CONFIG_SECURITY_NETWORK
> static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
> {
> - security_socket_getpeersec_dgram(sock, NULL, &scm->secid);
> + security_socket_getpeersec_dgram(sock, NULL, &scm->lsmblob);
> }
> #else
> static __inline__ void unix_get_peersec_dgram(struct socket *sock, struct scm_cookie *scm)
> @@ -97,7 +97,9 @@ static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct sc
> int err;
>
> if (test_bit(SOCK_PASSSEC, &sock->flags)) {
> - err = security_secid_to_secctx(scm->secid, &secdata, &seclen);
> + /* Scaffolding - it has to be element 0 for now */
> + err = security_secid_to_secctx(scm->lsmblob.secid[0],
> + &secdata, &seclen);
>
> if (!err) {
> put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
> diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
> index 82f341e84fae..2a5c868ce135 100644
> --- a/net/ipv4/ip_sockglue.c
> +++ b/net/ipv4/ip_sockglue.c
> @@ -130,15 +130,17 @@ static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb,
>
> static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
> {
> + struct lsmblob lb;
> char *secdata;
> - u32 seclen, secid;
> + u32 seclen;
> int err;
>
> - err = security_socket_getpeersec_dgram(NULL, skb, &secid);
> + err = security_socket_getpeersec_dgram(NULL, skb, &lb);
> if (err)
> return;
>
> - err = security_secid_to_secctx(secid, &secdata, &seclen);
> + /* Scaffolding - it has to be element 0 */
> + err = security_secid_to_secctx(lb.secid[0], &secdata, &seclen);
> if (err)
> return;
>
> diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
> index ddb838a1b74c..c50a004a1389 100644
> --- a/net/unix/af_unix.c
> +++ b/net/unix/af_unix.c
> @@ -143,17 +143,17 @@ static struct hlist_head *unix_sockets_unbound(void *addr)
> #ifdef CONFIG_SECURITY_NETWORK
> static void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb)
> {
> - UNIXCB(skb).secid = scm->secid;
> + UNIXCB(skb).lsmblob = scm->lsmblob;
> }
>
> static inline void unix_set_secdata(struct scm_cookie *scm, struct sk_buff *skb)
> {
> - scm->secid = UNIXCB(skb).secid;
> + scm->lsmblob = UNIXCB(skb).lsmblob;
> }
>
> static inline bool unix_secdata_eq(struct scm_cookie *scm, struct sk_buff *skb)
> {
> - return (scm->secid == UNIXCB(skb).secid);
> + return lsmblob_equal(&scm->lsmblob, &(UNIXCB(skb).lsmblob));
> }
> #else
> static inline void unix_get_secdata(struct scm_cookie *scm, struct sk_buff *skb)
> diff --git a/security/security.c b/security/security.c
> index f9c8e1926a0b..4e1eb2a54064 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -2120,10 +2120,22 @@ int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
> optval, optlen, len);
> }
>
> -int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
> +int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
> + struct lsmblob *blob)
> {
> - return call_int_hook(socket_getpeersec_dgram, -ENOPROTOOPT, sock,
> - skb, secid);
> + struct security_hook_list *hp;
> + int rc = -ENOPROTOOPT;
> +
> + hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_dgram,
> + list) {
> + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
> + continue;
> + rc = hp->hook.socket_getpeersec_dgram(sock, skb,
> + &blob->secid[hp->lsmid->slot]);
> + if (rc != 0)
> + break;
> + }
> + return rc;
> }
> EXPORT_SYMBOL(security_socket_getpeersec_dgram);
>
>
^ permalink raw reply
* Re: [PATCH v4 08/23] LSM: Use lsmblob in security_secctx_to_secid
From: John Johansen @ 2019-06-26 23:50 UTC (permalink / raw)
To: Casey Schaufler, casey.schaufler, jmorris, linux-security-module,
selinux
Cc: keescook, penguin-kernel, paul, sds
In-Reply-To: <20190626192234.11725-9-casey@schaufler-ca.com>
On 6/26/19 12:22 PM, Casey Schaufler wrote:
> Change security_secctx_to_secid() to fill in a lsmblob instead
> of a u32 secid. Multiple LSMs may be able to interpret the
> string, and this allows for setting whichever secid is
> appropriate. In some cases there is scaffolding where other
> interfaces have yet to be converted.
>
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
> ---
> include/linux/security.h | 5 +++--
> kernel/cred.c | 4 +---
> net/netfilter/nft_meta.c | 13 ++++++-------
> net/netfilter/xt_SECMARK.c | 5 ++++-
> net/netlabel/netlabel_unlabeled.c | 14 ++++++++------
> security/security.c | 18 +++++++++++++++---
> 6 files changed, 37 insertions(+), 22 deletions(-)
>
> diff --git a/include/linux/security.h b/include/linux/security.h
> index dcf20da87d1b..30337f1a9056 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -447,7 +447,8 @@ int security_setprocattr(const char *lsm, const char *name, void *value,
> int security_netlink_send(struct sock *sk, struct sk_buff *skb);
> int security_ismaclabel(const char *name);
> int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen);
> -int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid);
> +int security_secctx_to_secid(const char *secdata, u32 seclen,
> + struct lsmblob *blob);
> void security_release_secctx(char *secdata, u32 seclen);
>
> void security_inode_invalidate_secctx(struct inode *inode);
> @@ -1230,7 +1231,7 @@ static inline int security_secid_to_secctx(u32 secid, char **secdata, u32 *secle
>
> static inline int security_secctx_to_secid(const char *secdata,
> u32 seclen,
> - u32 *secid)
> + struct lsmblob *blob)
> {
> return -EOPNOTSUPP;
> }
> diff --git a/kernel/cred.c b/kernel/cred.c
> index 71c14dda107e..d70a2c02ced4 100644
> --- a/kernel/cred.c
> +++ b/kernel/cred.c
> @@ -725,14 +725,12 @@ EXPORT_SYMBOL(set_security_override);
> int set_security_override_from_ctx(struct cred *new, const char *secctx)
> {
> struct lsmblob blob;
> - u32 secid;
> int ret;
>
> - ret = security_secctx_to_secid(secctx, strlen(secctx), &secid);
> + ret = security_secctx_to_secid(secctx, strlen(secctx), &blob);
> if (ret < 0)
> return ret;
>
> - lsmblob_init(&blob, secid);
> return set_security_override(new, &blob);
> }
> EXPORT_SYMBOL(set_security_override_from_ctx);
> diff --git a/net/netfilter/nft_meta.c b/net/netfilter/nft_meta.c
> index 987d2d6ce624..054fb4b48d51 100644
> --- a/net/netfilter/nft_meta.c
> +++ b/net/netfilter/nft_meta.c
> @@ -576,21 +576,20 @@ static const struct nla_policy nft_secmark_policy[NFTA_SECMARK_MAX + 1] = {
>
> static int nft_secmark_compute_secid(struct nft_secmark *priv)
> {
> - u32 tmp_secid = 0;
> + struct lsmblob blob;
> int err;
>
> - err = security_secctx_to_secid(priv->ctx, strlen(priv->ctx), &tmp_secid);
> + err = security_secctx_to_secid(priv->ctx, strlen(priv->ctx), &blob);
> if (err)
> return err;
>
> - if (!tmp_secid)
> - return -ENOENT;
> -
> - err = security_secmark_relabel_packet(tmp_secid);
> + /* Using le[0] is scaffolding */
> + err = security_secmark_relabel_packet(blob.secid[0]);
> if (err)
> return err;
>
> - priv->secid = tmp_secid;
> + /* Using le[0] is scaffolding */
> + priv->secid = blob.secid[0];
> return 0;
> }
>
> diff --git a/net/netfilter/xt_SECMARK.c b/net/netfilter/xt_SECMARK.c
> index f16202d26c20..8081fadc30e9 100644
> --- a/net/netfilter/xt_SECMARK.c
> +++ b/net/netfilter/xt_SECMARK.c
> @@ -49,13 +49,14 @@ secmark_tg(struct sk_buff *skb, const struct xt_action_param *par)
>
> static int checkentry_lsm(struct xt_secmark_target_info *info)
> {
> + struct lsmblob blob;
> int err;
>
> info->secctx[SECMARK_SECCTX_MAX - 1] = '\0';
> info->secid = 0;
>
> err = security_secctx_to_secid(info->secctx, strlen(info->secctx),
> - &info->secid);
> + &blob);
> if (err) {
> if (err == -EINVAL)
> pr_info_ratelimited("invalid security context \'%s\'\n",
> @@ -63,6 +64,8 @@ static int checkentry_lsm(struct xt_secmark_target_info *info)
> return err;
> }
>
> + /* scaffolding during the transition */
> + info->secid = blob.secid[0];
> if (!info->secid) {
> pr_info_ratelimited("unable to map security context \'%s\'\n",
> info->secctx);
> diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
> index c92894c3e40a..2976370e41aa 100644
> --- a/net/netlabel/netlabel_unlabeled.c
> +++ b/net/netlabel/netlabel_unlabeled.c
> @@ -895,7 +895,7 @@ static int netlbl_unlabel_staticadd(struct sk_buff *skb,
> void *addr;
> void *mask;
> u32 addr_len;
> - u32 secid;
> + struct lsmblob blob;
> struct netlbl_audit audit_info;
>
> /* Don't allow users to add both IPv4 and IPv6 addresses for a
> @@ -919,12 +919,13 @@ static int netlbl_unlabel_staticadd(struct sk_buff *skb,
> ret_val = security_secctx_to_secid(
> nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
> nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
> - &secid);
> + &blob);
> if (ret_val != 0)
> return ret_val;
>
> + /* scaffolding with the [0] */
> return netlbl_unlhsh_add(&init_net,
> - dev_name, addr, mask, addr_len, secid,
> + dev_name, addr, mask, addr_len, blob.secid[0],
> &audit_info);
> }
>
> @@ -946,7 +947,7 @@ static int netlbl_unlabel_staticadddef(struct sk_buff *skb,
> void *addr;
> void *mask;
> u32 addr_len;
> - u32 secid;
> + struct lsmblob blob;
> struct netlbl_audit audit_info;
>
> /* Don't allow users to add both IPv4 and IPv6 addresses for a
> @@ -968,12 +969,13 @@ static int netlbl_unlabel_staticadddef(struct sk_buff *skb,
> ret_val = security_secctx_to_secid(
> nla_data(info->attrs[NLBL_UNLABEL_A_SECCTX]),
> nla_len(info->attrs[NLBL_UNLABEL_A_SECCTX]),
> - &secid);
> + &blob);
> if (ret_val != 0)
> return ret_val;
>
> + /* scaffolding with the [0] */
> return netlbl_unlhsh_add(&init_net,
> - NULL, addr, mask, addr_len, secid,
> + NULL, addr, mask, addr_len, blob.secid[0],
> &audit_info);
> }
>
> diff --git a/security/security.c b/security/security.c
> index 4e1eb2a54064..ad9aaa46ed04 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -1982,10 +1982,22 @@ int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
> }
> EXPORT_SYMBOL(security_secid_to_secctx);
>
> -int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
> +int security_secctx_to_secid(const char *secdata, u32 seclen,
> + struct lsmblob *blob)
> {
> - *secid = 0;
> - return call_int_hook(secctx_to_secid, 0, secdata, seclen, secid);
> + struct security_hook_list *hp;
> + int rc;
> +
> + lsmblob_init(blob, 0);
> + hlist_for_each_entry(hp, &security_hook_heads.secctx_to_secid, list) {
> + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
> + continue;
> + rc = hp->hook.secctx_to_secid(secdata, seclen,
> + &blob->secid[hp->lsmid->slot]);
> + if (rc != 0)
> + return rc;
> + }
> + return 0;
> }
> EXPORT_SYMBOL(security_secctx_to_secid);
>
>
^ permalink raw reply
* Re: [PATCH v4 09/23] LSM: Use lsmblob in security_secid_to_secctx
From: John Johansen @ 2019-06-26 23:51 UTC (permalink / raw)
To: Casey Schaufler, casey.schaufler, jmorris, linux-security-module,
selinux
Cc: keescook, penguin-kernel, paul, sds
In-Reply-To: <20190626192234.11725-10-casey@schaufler-ca.com>
On 6/26/19 12:22 PM, Casey Schaufler wrote:
> Change security_secid_to_secctx() to take a lsmblob as input
> instead of a u32 secid. It will then call the LSM hooks
> using the lsmblob element allocated for that module. The
> callers have been updated as well. This allows for the
> possibility that more than one module may be called upon
> to translate a secid to a string, as can occur in the
> audit code.
>
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
> ---
> drivers/android/binder.c | 4 +++-
> include/linux/security.h | 5 +++--
> include/net/scm.h | 5 ++---
> kernel/audit.c | 9 +++++++--
> kernel/auditsc.c | 14 ++++++++++----
> net/ipv4/ip_sockglue.c | 3 +--
> net/netfilter/nf_conntrack_netlink.c | 8 ++++++--
> net/netfilter/nf_conntrack_standalone.c | 4 +++-
> net/netfilter/nfnetlink_queue.c | 8 ++++++--
> net/netlabel/netlabel_unlabeled.c | 18 ++++++++++++++----
> net/netlabel/netlabel_user.c | 6 +++---
> security/security.c | 16 +++++++++++++---
> 12 files changed, 71 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index 8685882da64c..1962f6b8abd0 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -3120,9 +3120,11 @@ static void binder_transaction(struct binder_proc *proc,
>
> if (target_node && target_node->txn_security_ctx) {
> u32 secid;
> + struct lsmblob blob;
>
> security_task_getsecid(proc->tsk, &secid);
> - ret = security_secid_to_secctx(secid, &secctx, &secctx_sz);
> + lsmblob_init(&blob, secid);
> + ret = security_secid_to_secctx(&blob, &secctx, &secctx_sz);
> if (ret) {
> return_error = BR_FAILED_REPLY;
> return_error_param = ret;
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 30337f1a9056..7b4667cc4930 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -446,7 +446,7 @@ int security_setprocattr(const char *lsm, const char *name, void *value,
> size_t size);
> int security_netlink_send(struct sock *sk, struct sk_buff *skb);
> int security_ismaclabel(const char *name);
> -int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen);
> +int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen);
> int security_secctx_to_secid(const char *secdata, u32 seclen,
> struct lsmblob *blob);
> void security_release_secctx(char *secdata, u32 seclen);
> @@ -1224,7 +1224,8 @@ static inline int security_ismaclabel(const char *name)
> return 0;
> }
>
> -static inline int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
> +static inline int security_secid_to_secctx(struct lsmblob *blob,
> + char **secdata, u32 *seclen)
> {
> return -EOPNOTSUPP;
> }
> diff --git a/include/net/scm.h b/include/net/scm.h
> index e2e71c4bf9d0..31ae605fcc0a 100644
> --- a/include/net/scm.h
> +++ b/include/net/scm.h
> @@ -97,9 +97,8 @@ static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct sc
> int err;
>
> if (test_bit(SOCK_PASSSEC, &sock->flags)) {
> - /* Scaffolding - it has to be element 0 for now */
> - err = security_secid_to_secctx(scm->lsmblob.secid[0],
> - &secdata, &seclen);
> + err = security_secid_to_secctx(&scm->lsmblob, &secdata,
> + &seclen);
>
> if (!err) {
> put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
> diff --git a/kernel/audit.c b/kernel/audit.c
> index c89ea48c70a6..d0338411d75d 100644
> --- a/kernel/audit.c
> +++ b/kernel/audit.c
> @@ -1430,7 +1430,10 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
> case AUDIT_SIGNAL_INFO:
> len = 0;
> if (audit_sig_sid) {
> - err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
> + struct lsmblob blob;
> +
> + lsmblob_init(&blob, audit_sig_sid);
> + err = security_secid_to_secctx(&blob, &ctx, &len);
> if (err)
> return err;
> }
> @@ -2073,12 +2076,14 @@ int audit_log_task_context(struct audit_buffer *ab)
> unsigned len;
> int error;
> u32 sid;
> + struct lsmblob blob;
>
> security_task_getsecid(current, &sid);
> if (!sid)
> return 0;
>
> - error = security_secid_to_secctx(sid, &ctx, &len);
> + lsmblob_init(&blob, sid);
> + error = security_secid_to_secctx(&blob, &ctx, &len);
> if (error) {
> if (error != -EINVAL)
> goto error_path;
> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index 18ee5556c086..d31914088a82 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -947,6 +947,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
> char *ctx = NULL;
> u32 len;
> int rc = 0;
> + struct lsmblob blob;
>
> ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
> if (!ab)
> @@ -956,7 +957,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
> from_kuid(&init_user_ns, auid),
> from_kuid(&init_user_ns, uid), sessionid);
> if (sid) {
> - if (security_secid_to_secctx(sid, &ctx, &len)) {
> + lsmblob_init(&blob, sid);
> + if (security_secid_to_secctx(&blob, &ctx, &len)) {
> audit_log_format(ab, " obj=(none)");
> rc = 1;
> } else {
> @@ -1198,7 +1200,10 @@ static void show_special(struct audit_context *context, int *call_panic)
> if (osid) {
> char *ctx = NULL;
> u32 len;
> - if (security_secid_to_secctx(osid, &ctx, &len)) {
> + struct lsmblob blob;
> +
> + lsmblob_init(&blob, osid);
> + if (security_secid_to_secctx(&blob, &ctx, &len)) {
> audit_log_format(ab, " osid=%u", osid);
> *call_panic = 1;
> } else {
> @@ -1349,9 +1354,10 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
> if (n->osid != 0) {
> char *ctx = NULL;
> u32 len;
> + struct lsmblob blob;
>
> - if (security_secid_to_secctx(
> - n->osid, &ctx, &len)) {
> + lsmblob_init(&blob, n->osid);
> + if (security_secid_to_secctx(&blob, &ctx, &len)) {
> audit_log_format(ab, " osid=%u", n->osid);
> if (call_panic)
> *call_panic = 2;
> diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
> index 2a5c868ce135..e05f4ef68bd8 100644
> --- a/net/ipv4/ip_sockglue.c
> +++ b/net/ipv4/ip_sockglue.c
> @@ -139,8 +139,7 @@ static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
> if (err)
> return;
>
> - /* Scaffolding - it has to be element 0 */
> - err = security_secid_to_secctx(lb.secid[0], &secdata, &seclen);
> + err = security_secid_to_secctx(&lb, &secdata, &seclen);
> if (err)
> return;
>
> diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
> index 66c596d287a5..ca0968f13240 100644
> --- a/net/netfilter/nf_conntrack_netlink.c
> +++ b/net/netfilter/nf_conntrack_netlink.c
> @@ -330,8 +330,10 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
> struct nlattr *nest_secctx;
> int len, ret;
> char *secctx;
> + struct lsmblob blob;
>
> - ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
> + lsmblob_init(&blob, ct->secmark);
> + ret = security_secid_to_secctx(&blob, &secctx, &len);
> if (ret)
> return 0;
>
> @@ -615,8 +617,10 @@ static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
> {
> #ifdef CONFIG_NF_CONNTRACK_SECMARK
> int len, ret;
> + struct lsmblob blob;
>
> - ret = security_secid_to_secctx(ct->secmark, NULL, &len);
> + lsmblob_init(&blob, ct->secmark);
> + ret = security_secid_to_secctx(&blob, NULL, &len);
> if (ret)
> return 0;
>
> diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
> index c2ae14c720b4..c793103f3cd7 100644
> --- a/net/netfilter/nf_conntrack_standalone.c
> +++ b/net/netfilter/nf_conntrack_standalone.c
> @@ -175,8 +175,10 @@ static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
> int ret;
> u32 len;
> char *secctx;
> + struct lsmblob blob;
>
> - ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
> + lsmblob_init(&blob, ct->secmark);
> + ret = security_secid_to_secctx(&blob, &secctx, &len);
> if (ret)
> return;
>
> diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
> index 0dcc3592d053..59211bff90ab 100644
> --- a/net/netfilter/nfnetlink_queue.c
> +++ b/net/netfilter/nfnetlink_queue.c
> @@ -309,13 +309,17 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
> {
> u32 seclen = 0;
> #if IS_ENABLED(CONFIG_NETWORK_SECMARK)
> + struct lsmblob blob;
> +
> if (!skb || !sk_fullsock(skb->sk))
> return 0;
>
> read_lock_bh(&skb->sk->sk_callback_lock);
>
> - if (skb->secmark)
> - security_secid_to_secctx(skb->secmark, secdata, &seclen);
> + if (skb->secmark) {
> + lsmblob_init(&blob, skb->secmark);
> + security_secid_to_secctx(&blob, secdata, &seclen);
> + }
>
> read_unlock_bh(&skb->sk->sk_callback_lock);
> #endif
> diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
> index 2976370e41aa..2d8dd5b84457 100644
> --- a/net/netlabel/netlabel_unlabeled.c
> +++ b/net/netlabel/netlabel_unlabeled.c
> @@ -389,6 +389,7 @@ int netlbl_unlhsh_add(struct net *net,
> struct audit_buffer *audit_buf = NULL;
> char *secctx = NULL;
> u32 secctx_len;
> + struct lsmblob blob;
>
> if (addr_len != sizeof(struct in_addr) &&
> addr_len != sizeof(struct in6_addr))
> @@ -451,7 +452,8 @@ int netlbl_unlhsh_add(struct net *net,
> unlhsh_add_return:
> rcu_read_unlock();
> if (audit_buf != NULL) {
> - if (security_secid_to_secctx(secid,
> + lsmblob_init(&blob, secid);
> + if (security_secid_to_secctx(&blob,
> &secctx,
> &secctx_len) == 0) {
> audit_log_format(audit_buf, " sec_obj=%s", secctx);
> @@ -488,6 +490,7 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
> struct net_device *dev;
> char *secctx;
> u32 secctx_len;
> + struct lsmblob blob;
>
> spin_lock(&netlbl_unlhsh_lock);
> list_entry = netlbl_af4list_remove(addr->s_addr, mask->s_addr,
> @@ -507,8 +510,10 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
> addr->s_addr, mask->s_addr);
> if (dev != NULL)
> dev_put(dev);
> + if (entry != NULL)
> + lsmblob_init(&blob, entry->secid);
> if (entry != NULL &&
> - security_secid_to_secctx(entry->secid,
> + security_secid_to_secctx(&blob,
> &secctx, &secctx_len) == 0) {
> audit_log_format(audit_buf, " sec_obj=%s", secctx);
> security_release_secctx(secctx, secctx_len);
> @@ -550,6 +555,7 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
> struct net_device *dev;
> char *secctx;
> u32 secctx_len;
> + struct lsmblob blob;
>
> spin_lock(&netlbl_unlhsh_lock);
> list_entry = netlbl_af6list_remove(addr, mask, &iface->addr6_list);
> @@ -568,8 +574,10 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
> addr, mask);
> if (dev != NULL)
> dev_put(dev);
> + if (entry != NULL)
> + lsmblob_init(&blob, entry->secid);
> if (entry != NULL &&
> - security_secid_to_secctx(entry->secid,
> + security_secid_to_secctx(&blob,
> &secctx, &secctx_len) == 0) {
> audit_log_format(audit_buf, " sec_obj=%s", secctx);
> security_release_secctx(secctx, secctx_len);
> @@ -1090,6 +1098,7 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
> u32 secid;
> char *secctx;
> u32 secctx_len;
> + struct lsmblob blob;
>
> data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,
> cb_arg->seq, &netlbl_unlabel_gnl_family,
> @@ -1144,7 +1153,8 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
> secid = addr6->secid;
> }
>
> - ret_val = security_secid_to_secctx(secid, &secctx, &secctx_len);
> + lsmblob_init(&blob, secid);
> + ret_val = security_secid_to_secctx(&blob, &secctx, &secctx_len);
> if (ret_val != 0)
> goto list_cb_failure;
> ret_val = nla_put(cb_arg->skb,
> diff --git a/net/netlabel/netlabel_user.c b/net/netlabel/netlabel_user.c
> index 4676f5bb16ae..2ccc6567e2a2 100644
> --- a/net/netlabel/netlabel_user.c
> +++ b/net/netlabel/netlabel_user.c
> @@ -100,6 +100,7 @@ struct audit_buffer *netlbl_audit_start_common(int type,
> struct audit_buffer *audit_buf;
> char *secctx;
> u32 secctx_len;
> + struct lsmblob blob;
>
> if (audit_enabled == AUDIT_OFF)
> return NULL;
> @@ -112,10 +113,9 @@ struct audit_buffer *netlbl_audit_start_common(int type,
> from_kuid(&init_user_ns, audit_info->loginuid),
> audit_info->sessionid);
>
> + lsmblob_init(&blob, audit_info->secid);
> if (audit_info->secid != 0 &&
> - security_secid_to_secctx(audit_info->secid,
> - &secctx,
> - &secctx_len) == 0) {
> + security_secid_to_secctx(&blob, &secctx, &secctx_len) == 0) {
> audit_log_format(audit_buf, " subj=%s", secctx);
> security_release_secctx(secctx, secctx_len);
> }
> diff --git a/security/security.c b/security/security.c
> index ad9aaa46ed04..0c7784a243e7 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -1975,10 +1975,20 @@ int security_ismaclabel(const char *name)
> }
> EXPORT_SYMBOL(security_ismaclabel);
>
> -int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
> +int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen)
> {
> - return call_int_hook(secid_to_secctx, -EOPNOTSUPP, secid, secdata,
> - seclen);
> + struct security_hook_list *hp;
> + int rc;
> +
> + hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) {
> + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
> + continue;
> + rc = hp->hook.secid_to_secctx(blob->secid[hp->lsmid->slot],
> + secdata, seclen);
> + if (rc != 0)
> + return rc;
> + }
> + return 0;
> }
> EXPORT_SYMBOL(security_secid_to_secctx);
>
>
^ permalink raw reply
* Re: [PATCH v4 10/23] LSM: Use lsmblob in security_ipc_getsecid
From: John Johansen @ 2019-06-26 23:53 UTC (permalink / raw)
To: Casey Schaufler, casey.schaufler, jmorris, linux-security-module,
selinux
Cc: keescook, penguin-kernel, paul, sds
In-Reply-To: <20190626192234.11725-11-casey@schaufler-ca.com>
On 6/26/19 12:22 PM, Casey Schaufler wrote:
> There may be more than one LSM that provides IPC data
> for auditing. Change security_ipc_getsecid() to fill in
> a lsmblob structure instead of the u32 secid. The
> audit data structure containing the secid will be updated
> later, so there is a bit of scaffolding here.
>
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
> ---
> include/linux/security.h | 7 ++++---
> kernel/auditsc.c | 5 ++++-
> security/security.c | 12 +++++++++---
> 3 files changed, 17 insertions(+), 7 deletions(-)
>
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 7b4667cc4930..41dc3053094e 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -417,7 +417,7 @@ int security_task_prctl(int option, unsigned long arg2, unsigned long arg3,
> unsigned long arg4, unsigned long arg5);
> void security_task_to_inode(struct task_struct *p, struct inode *inode);
> int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag);
> -void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid);
> +void security_ipc_getsecid(struct kern_ipc_perm *ipcp, struct lsmblob *blob);
> int security_msg_msg_alloc(struct msg_msg *msg);
> void security_msg_msg_free(struct msg_msg *msg);
> int security_msg_queue_alloc(struct kern_ipc_perm *msq);
> @@ -1102,9 +1102,10 @@ static inline int security_ipc_permission(struct kern_ipc_perm *ipcp,
> return 0;
> }
>
> -static inline void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
> +static inline void security_ipc_getsecid(struct kern_ipc_perm *ipcp,
> + struct lsmblob *blob)
> {
> - *secid = 0;
> + lsmblob_init(blob, 0);
> }
>
> static inline int security_msg_msg_alloc(struct msg_msg *msg)
> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index d31914088a82..148733ec3c72 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -2268,11 +2268,14 @@ void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
> void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
> {
> struct audit_context *context = audit_context();
> + struct lsmblob blob;
> context->ipc.uid = ipcp->uid;
> context->ipc.gid = ipcp->gid;
> context->ipc.mode = ipcp->mode;
> context->ipc.has_perm = 0;
> - security_ipc_getsecid(ipcp, &context->ipc.osid);
> + security_ipc_getsecid(ipcp, &blob);
> + /* scaffolding on the [0] - change "osid" to a lsmblob */
> + context->ipc.osid = blob.secid[0];
> context->type = AUDIT_IPC;
> }
>
> diff --git a/security/security.c b/security/security.c
> index 0c7784a243e7..5245d4d1e799 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -1795,10 +1795,16 @@ int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
> return call_int_hook(ipc_permission, 0, ipcp, flag);
> }
>
> -void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
> +void security_ipc_getsecid(struct kern_ipc_perm *ipcp, struct lsmblob *blob)
> {
> - *secid = 0;
> - call_void_hook(ipc_getsecid, ipcp, secid);
> + struct security_hook_list *hp;
> +
> + lsmblob_init(blob, 0);
> + hlist_for_each_entry(hp, &security_hook_heads.ipc_getsecid, list) {
> + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
> + continue;
> + hp->hook.ipc_getsecid(ipcp, &blob->secid[hp->lsmid->slot]);
> + }
> }
>
> int security_msg_msg_alloc(struct msg_msg *msg)
>
^ permalink raw reply
* Re: [PATCH v4 11/23] LSM: Use lsmblob in security_task_getsecid
From: John Johansen @ 2019-06-26 23:55 UTC (permalink / raw)
To: Casey Schaufler, casey.schaufler, jmorris, linux-security-module,
selinux
Cc: keescook, penguin-kernel, paul, sds
In-Reply-To: <20190626192234.11725-12-casey@schaufler-ca.com>
On 6/26/19 12:22 PM, Casey Schaufler wrote:
> Change the security_task_getsecid() interface to fill in
> a lsmblob structure instead of a u32 secid in support of
> LSM stacking. Audit interfaces will need to collect all
> possible secids for possible reporting.
>
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
> ---
> drivers/android/binder.c | 4 +---
> include/linux/security.h | 7 +++---
> kernel/audit.c | 6 ++---
> kernel/auditfilter.c | 4 +---
> kernel/auditsc.c | 22 ++++++++++++------
> net/netlabel/netlabel_unlabeled.c | 5 +++-
> net/netlabel/netlabel_user.h | 6 ++++-
> security/integrity/ima/ima_appraise.c | 4 +++-
> security/integrity/ima/ima_main.c | 33 +++++++++++++++------------
> security/security.c | 12 +++++++---
> 10 files changed, 63 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index 1962f6b8abd0..144ac4f1c24f 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -3119,11 +3119,9 @@ static void binder_transaction(struct binder_proc *proc,
> t->priority = task_nice(current);
>
> if (target_node && target_node->txn_security_ctx) {
> - u32 secid;
> struct lsmblob blob;
>
> - security_task_getsecid(proc->tsk, &secid);
> - lsmblob_init(&blob, secid);
> + security_task_getsecid(proc->tsk, &blob);
> ret = security_secid_to_secctx(&blob, &secctx, &secctx_sz);
> if (ret) {
> return_error = BR_FAILED_REPLY;
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 41dc3053094e..cfd7cf4b0be9 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -400,7 +400,7 @@ int security_task_fix_setuid(struct cred *new, const struct cred *old,
> int security_task_setpgid(struct task_struct *p, pid_t pgid);
> int security_task_getpgid(struct task_struct *p);
> int security_task_getsid(struct task_struct *p);
> -void security_task_getsecid(struct task_struct *p, u32 *secid);
> +void security_task_getsecid(struct task_struct *p, struct lsmblob *blob);
> int security_task_setnice(struct task_struct *p, int nice);
> int security_task_setioprio(struct task_struct *p, int ioprio);
> int security_task_getioprio(struct task_struct *p);
> @@ -1029,9 +1029,10 @@ static inline int security_task_getsid(struct task_struct *p)
> return 0;
> }
>
> -static inline void security_task_getsecid(struct task_struct *p, u32 *secid)
> +static inline void security_task_getsecid(struct task_struct *p,
> + struct lsmblob *blob)
> {
> - *secid = 0;
> + lsmblob_init(blob, 0);
> }
>
> static inline int security_task_setnice(struct task_struct *p, int nice)
> diff --git a/kernel/audit.c b/kernel/audit.c
> index d0338411d75d..a0205f3c23c7 100644
> --- a/kernel/audit.c
> +++ b/kernel/audit.c
> @@ -2075,14 +2075,12 @@ int audit_log_task_context(struct audit_buffer *ab)
> char *ctx = NULL;
> unsigned len;
> int error;
> - u32 sid;
> struct lsmblob blob;
>
> - security_task_getsecid(current, &sid);
> - if (!sid)
> + security_task_getsecid(current, &blob);
> + if (!lsmblob_is_set(&blob))
> return 0;
>
> - lsmblob_init(&blob, sid);
> error = security_secid_to_secctx(&blob, &ctx, &len);
> if (error) {
> if (error != -EINVAL)
> diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
> index 8786b95b60bd..8f244c98bb57 100644
> --- a/kernel/auditfilter.c
> +++ b/kernel/auditfilter.c
> @@ -1323,7 +1323,6 @@ int audit_filter(int msgtype, unsigned int listtype)
> for (i = 0; i < e->rule.field_count; i++) {
> struct audit_field *f = &e->rule.fields[i];
> pid_t pid;
> - u32 sid;
> struct lsmblob blob;
>
> switch (f->type) {
> @@ -1354,8 +1353,7 @@ int audit_filter(int msgtype, unsigned int listtype)
> case AUDIT_SUBJ_SEN:
> case AUDIT_SUBJ_CLR:
> if (f->lsm_rule) {
> - security_task_getsecid(current, &sid);
> - lsmblob_init(&blob, sid);
> + security_task_getsecid(current, &blob);
> result = security_audit_rule_match(
> &blob, f->type,
> f->op, f->lsm_rule);
> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index 148733ec3c72..7112fe31684d 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -444,7 +444,6 @@ static int audit_filter_rules(struct task_struct *tsk,
> {
> const struct cred *cred;
> int i, need_sid = 1;
> - u32 sid;
> struct lsmblob blob;
> unsigned int sessionid;
>
> @@ -628,10 +627,9 @@ static int audit_filter_rules(struct task_struct *tsk,
> logged upon error */
> if (f->lsm_rule) {
> if (need_sid) {
> - security_task_getsecid(tsk, &sid);
> + security_task_getsecid(tsk, &blob);
> need_sid = 0;
> }
> - lsmblob_init(&blob, sid);
> result = security_audit_rule_match(&blob,
> f->type,
> f->op,
> @@ -2365,12 +2363,15 @@ int __audit_sockaddr(int len, void *a)
> void __audit_ptrace(struct task_struct *t)
> {
> struct audit_context *context = audit_context();
> + struct lsmblob blob;
>
> context->target_pid = task_tgid_nr(t);
> context->target_auid = audit_get_loginuid(t);
> context->target_uid = task_uid(t);
> context->target_sessionid = audit_get_sessionid(t);
> - security_task_getsecid(t, &context->target_sid);
> + security_task_getsecid(t, &blob);
> + /* scaffolding - until target_sid is converted */
> + context->target_sid = blob.secid[0];
> memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
> }
>
> @@ -2387,6 +2388,7 @@ int audit_signal_info(int sig, struct task_struct *t)
> struct audit_aux_data_pids *axp;
> struct audit_context *ctx = audit_context();
> kuid_t uid = current_uid(), auid, t_uid = task_uid(t);
> + struct lsmblob blob;
>
> if (auditd_test_task(t) &&
> (sig == SIGTERM || sig == SIGHUP ||
> @@ -2397,7 +2399,9 @@ int audit_signal_info(int sig, struct task_struct *t)
> audit_sig_uid = auid;
> else
> audit_sig_uid = uid;
> - security_task_getsecid(current, &audit_sig_sid);
> + security_task_getsecid(current, &blob);
> + /* scaffolding until audit_sig_sid is converted */
> + audit_sig_sid = blob.secid[0];
> }
>
> if (!audit_signals || audit_dummy_context())
> @@ -2410,7 +2414,9 @@ int audit_signal_info(int sig, struct task_struct *t)
> ctx->target_auid = audit_get_loginuid(t);
> ctx->target_uid = t_uid;
> ctx->target_sessionid = audit_get_sessionid(t);
> - security_task_getsecid(t, &ctx->target_sid);
> + security_task_getsecid(t, &blob);
> + /* scaffolding until target_sid is converted */
> + ctx->target_sid = blob.secid[0];
> memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
> return 0;
> }
> @@ -2431,7 +2437,9 @@ int audit_signal_info(int sig, struct task_struct *t)
> axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
> axp->target_uid[axp->pid_count] = t_uid;
> axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
> - security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
> + security_task_getsecid(t, &blob);
> + /* scaffolding until target_sid is converted */
> + axp->target_sid[axp->pid_count] = blob.secid[0];
> memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
> axp->pid_count++;
>
> diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
> index 2d8dd5b84457..2294aa9471e6 100644
> --- a/net/netlabel/netlabel_unlabeled.c
> +++ b/net/netlabel/netlabel_unlabeled.c
> @@ -1552,11 +1552,14 @@ int __init netlbl_unlabel_defconf(void)
> int ret_val;
> struct netlbl_dom_map *entry;
> struct netlbl_audit audit_info;
> + struct lsmblob blob;
>
> /* Only the kernel is allowed to call this function and the only time
> * it is called is at bootup before the audit subsystem is reporting
> * messages so don't worry to much about these values. */
> - security_task_getsecid(current, &audit_info.secid);
> + security_task_getsecid(current, &blob);
> + /* scaffolding until audit_info.secid is converted */
> + audit_info.secid = blob.secid[0];
> audit_info.loginuid = GLOBAL_ROOT_UID;
> audit_info.sessionid = 0;
>
> diff --git a/net/netlabel/netlabel_user.h b/net/netlabel/netlabel_user.h
> index 4a397cde1a48..ab88baaaa50d 100644
> --- a/net/netlabel/netlabel_user.h
> +++ b/net/netlabel/netlabel_user.h
> @@ -48,7 +48,11 @@
> static inline void netlbl_netlink_auditinfo(struct sk_buff *skb,
> struct netlbl_audit *audit_info)
> {
> - security_task_getsecid(current, &audit_info->secid);
> + struct lsmblob blob;
> +
> + security_task_getsecid(current, &blob);
> + /* scaffolding until secid is converted */
> + audit_info->secid = blob.secid[0];
> audit_info->loginuid = audit_get_loginuid(current);
> audit_info->sessionid = audit_get_sessionid(current);
> }
> diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
> index 5fb7127bbe68..85c7692fc4a3 100644
> --- a/security/integrity/ima/ima_appraise.c
> +++ b/security/integrity/ima/ima_appraise.c
> @@ -51,11 +51,13 @@ bool is_ima_appraise_enabled(void)
> int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func)
> {
> u32 secid;
> + struct lsmblob blob;
>
> if (!ima_appraise)
> return 0;
>
> - security_task_getsecid(current, &secid);
> + security_task_getsecid(current, &blob);
> + lsmblob_secid(&blob, &secid);
> return ima_match_policy(inode, current_cred(), secid, func, mask,
> IMA_APPRAISE | IMA_HASH, NULL);
> }
> diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
> index 357edd140c09..fefa848cf0c7 100644
> --- a/security/integrity/ima/ima_main.c
> +++ b/security/integrity/ima/ima_main.c
> @@ -335,12 +335,13 @@ static int process_measurement(struct file *file, const struct cred *cred,
> */
> int ima_file_mmap(struct file *file, unsigned long prot)
> {
> - u32 secid;
> + struct lsmblob blob;
>
> if (file && (prot & PROT_EXEC)) {
> - security_task_getsecid(current, &secid);
> - return process_measurement(file, current_cred(), secid, NULL,
> - 0, MAY_EXEC, MMAP_CHECK);
> + security_task_getsecid(current, &blob);
> + /* scaffolding - until process_measurement changes */
> + return process_measurement(file, current_cred(), blob.secid[0],
> + NULL, 0, MAY_EXEC, MMAP_CHECK);
> }
>
> return 0;
> @@ -363,10 +364,12 @@ int ima_bprm_check(struct linux_binprm *bprm)
> {
> int ret;
> u32 secid;
> + struct lsmblob blob;
>
> - security_task_getsecid(current, &secid);
> - ret = process_measurement(bprm->file, current_cred(), secid, NULL, 0,
> - MAY_EXEC, BPRM_CHECK);
> + security_task_getsecid(current, &blob);
> + /* scaffolding until process_measurement changes */
> + ret = process_measurement(bprm->file, current_cred(), blob.secid[0],
> + NULL, 0, MAY_EXEC, BPRM_CHECK);
> if (ret)
> return ret;
>
> @@ -387,10 +390,11 @@ int ima_bprm_check(struct linux_binprm *bprm)
> */
> int ima_file_check(struct file *file, int mask)
> {
> - u32 secid;
> + struct lsmblob blob;
>
> - security_task_getsecid(current, &secid);
> - return process_measurement(file, current_cred(), secid, NULL, 0,
> + security_task_getsecid(current, &blob);
> + /* scaffolding until process_measurement changes */
> + return process_measurement(file, current_cred(), blob.secid[0], NULL, 0,
> mask & (MAY_READ | MAY_WRITE | MAY_EXEC |
> MAY_APPEND), FILE_CHECK);
> }
> @@ -499,7 +503,7 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size,
> enum kernel_read_file_id read_id)
> {
> enum ima_hooks func;
> - u32 secid;
> + struct lsmblob blob;
>
> if (!file && read_id == READING_FIRMWARE) {
> if ((ima_appraise & IMA_APPRAISE_FIRMWARE) &&
> @@ -521,9 +525,10 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size,
> }
>
> func = read_idmap[read_id] ?: FILE_CHECK;
> - security_task_getsecid(current, &secid);
> - return process_measurement(file, current_cred(), secid, buf, size,
> - MAY_READ, func);
> + security_task_getsecid(current, &blob);
> + /* scaffolding until process_measurement changes */
> + return process_measurement(file, current_cred(), blob.secid[0], buf,
> + size, MAY_READ, func);
> }
>
> /**
> diff --git a/security/security.c b/security/security.c
> index 5245d4d1e799..2f123003b0b3 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -1712,10 +1712,16 @@ int security_task_getsid(struct task_struct *p)
> return call_int_hook(task_getsid, 0, p);
> }
>
> -void security_task_getsecid(struct task_struct *p, u32 *secid)
> +void security_task_getsecid(struct task_struct *p, struct lsmblob *blob)
> {
> - *secid = 0;
> - call_void_hook(task_getsecid, p, secid);
> + struct security_hook_list *hp;
> +
> + lsmblob_init(blob, 0);
> + hlist_for_each_entry(hp, &security_hook_heads.task_getsecid, list) {
> + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
> + continue;
> + hp->hook.task_getsecid(p, &blob->secid[hp->lsmid->slot]);
> + }
> }
> EXPORT_SYMBOL(security_task_getsecid);
>
>
^ permalink raw reply
* Re: [PATCH v4 12/23] LSM: Use lsmblob in security_inode_getsecid
From: John Johansen @ 2019-06-26 23:56 UTC (permalink / raw)
To: Casey Schaufler, casey.schaufler, jmorris, linux-security-module,
selinux
Cc: keescook, penguin-kernel, paul, sds
In-Reply-To: <20190626192234.11725-13-casey@schaufler-ca.com>
On 6/26/19 12:22 PM, Casey Schaufler wrote:
> Change the security_inode_getsecid() interface to fill in a
> lsmblob structure instead of a u32 secid. This allows for its
> callers to gather data from all registered LSMs. Data is provided
> for IMA and audit.
>
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
> ---
> include/linux/security.h | 7 ++++---
> kernel/auditsc.c | 6 +++++-
> security/integrity/ima/ima_policy.c | 4 +---
> security/security.c | 11 +++++++++--
> 4 files changed, 19 insertions(+), 9 deletions(-)
>
> diff --git a/include/linux/security.h b/include/linux/security.h
> index cfd7cf4b0be9..2d81cac418e3 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -362,7 +362,7 @@ int security_inode_killpriv(struct dentry *dentry);
> int security_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc);
> int security_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags);
> int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size);
> -void security_inode_getsecid(struct inode *inode, u32 *secid);
> +void security_inode_getsecid(struct inode *inode, struct lsmblob *blob);
> int security_inode_copy_up(struct dentry *src, struct cred **new);
> int security_inode_copy_up_xattr(const char *name);
> int security_file_permission(struct file *file, int mask);
> @@ -858,9 +858,10 @@ static inline int security_inode_listsecurity(struct inode *inode, char *buffer,
> return 0;
> }
>
> -static inline void security_inode_getsecid(struct inode *inode, u32 *secid)
> +static inline void security_inode_getsecid(struct inode *inode,
> + struct lsmblob *blob)
> {
> - *secid = 0;
> + lsmblob_init(blob, 0);
> }
>
> static inline int security_inode_copy_up(struct dentry *src, struct cred **new)
> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index 7112fe31684d..54797c0fc3b7 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -1910,13 +1910,17 @@ static inline int audit_copy_fcaps(struct audit_names *name,
> void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
> struct inode *inode, unsigned int flags)
> {
> + struct lsmblob blob;
> +
> name->ino = inode->i_ino;
> name->dev = inode->i_sb->s_dev;
> name->mode = inode->i_mode;
> name->uid = inode->i_uid;
> name->gid = inode->i_gid;
> name->rdev = inode->i_rdev;
> - security_inode_getsecid(inode, &name->osid);
> + security_inode_getsecid(inode, &blob);
> + /* scaffolding until osid is updated */
> + name->osid = blob.secid[0];
> if (flags & AUDIT_INODE_NOEVAL) {
> name->fcap_ver = -1;
> return;
> diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
> index e7b8ce942950..92ee3d984c73 100644
> --- a/security/integrity/ima/ima_policy.c
> +++ b/security/integrity/ima/ima_policy.c
> @@ -326,7 +326,6 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
> return false;
> for (i = 0; i < MAX_LSM_RULES; i++) {
> int rc = 0;
> - u32 osid;
> struct lsmblob blob;
> int retried = 0;
>
> @@ -337,8 +336,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
> case LSM_OBJ_USER:
> case LSM_OBJ_ROLE:
> case LSM_OBJ_TYPE:
> - security_inode_getsecid(inode, &osid);
> - lsmblob_init(&blob, osid);
> + security_inode_getsecid(inode, &blob);
> rc = security_filter_rule_match(&blob,
> rule->lsm[i].type,
> Audit_equal,
> diff --git a/security/security.c b/security/security.c
> index 2f123003b0b3..91388553d3d7 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -1404,9 +1404,16 @@ int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer
> }
> EXPORT_SYMBOL(security_inode_listsecurity);
>
> -void security_inode_getsecid(struct inode *inode, u32 *secid)
> +void security_inode_getsecid(struct inode *inode, struct lsmblob *blob)
> {
> - call_void_hook(inode_getsecid, inode, secid);
> + struct security_hook_list *hp;
> +
> + lsmblob_init(blob, 0);
> + hlist_for_each_entry(hp, &security_hook_heads.inode_getsecid, list) {
> + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
> + continue;
> + hp->hook.inode_getsecid(inode, &blob->secid[hp->lsmid->slot]);
> + }
> }
>
> int security_inode_copy_up(struct dentry *src, struct cred **new)
>
^ permalink raw reply
* Re: [PATCH v4 13/23] LSM: Use lsmblob in security_cred_getsecid
From: John Johansen @ 2019-06-26 23:57 UTC (permalink / raw)
To: Casey Schaufler, casey.schaufler, jmorris, linux-security-module,
selinux
Cc: keescook, penguin-kernel, paul, sds
In-Reply-To: <20190626192234.11725-14-casey@schaufler-ca.com>
On 6/26/19 12:22 PM, Casey Schaufler wrote:
> Change the security_cred_getsecid() interface to fill in a
> lsmblob instead of a u32 secid. The associated data elements
> in the audit sub-system are changed from a secid to a lsmblob
> to accomodate multiple possible LSM audit users.
>
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
> ---
> include/linux/security.h | 2 +-
> kernel/audit.c | 14 +++++-------
> kernel/audit.h | 5 +++--
> kernel/auditsc.c | 37 +++++++++++--------------------
> security/integrity/ima/ima_main.c | 8 +++----
> security/security.c | 12 +++++++---
> 6 files changed, 36 insertions(+), 42 deletions(-)
>
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 2d81cac418e3..d310fa3942ce 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -387,7 +387,7 @@ int security_cred_alloc_blank(struct cred *cred, gfp_t gfp);
> void security_cred_free(struct cred *cred);
> int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp);
> void security_transfer_creds(struct cred *new, const struct cred *old);
> -void security_cred_getsecid(const struct cred *c, u32 *secid);
> +void security_cred_getsecid(const struct cred *c, struct lsmblob *blob);
> int security_kernel_act_as(struct cred *new, struct lsmblob *blob);
> int security_kernel_create_files_as(struct cred *new, struct inode *inode);
> int security_kernel_module_request(char *kmod_name);
> diff --git a/kernel/audit.c b/kernel/audit.c
> index a0205f3c23c7..1b51e907f131 100644
> --- a/kernel/audit.c
> +++ b/kernel/audit.c
> @@ -137,7 +137,7 @@ static u32 audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME;
> /* The identity of the user shutting down the audit system. */
> kuid_t audit_sig_uid = INVALID_UID;
> pid_t audit_sig_pid = -1;
> -u32 audit_sig_sid = 0;
> +struct lsmblob audit_sig_lsm;
>
> /* Records can be lost in several ways:
> 0) [suppressed in audit_alloc]
> @@ -1429,23 +1429,21 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
> }
> case AUDIT_SIGNAL_INFO:
> len = 0;
> - if (audit_sig_sid) {
> - struct lsmblob blob;
> -
> - lsmblob_init(&blob, audit_sig_sid);
> - err = security_secid_to_secctx(&blob, &ctx, &len);
> + if (lsmblob_is_set(&audit_sig_lsm)) {
> + err = security_secid_to_secctx(&audit_sig_lsm, &ctx,
> + &len);
> if (err)
> return err;
> }
> sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
> if (!sig_data) {
> - if (audit_sig_sid)
> + if (lsmblob_is_set(&audit_sig_lsm))
> security_release_secctx(ctx, len);
> return -ENOMEM;
> }
> sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
> sig_data->pid = audit_sig_pid;
> - if (audit_sig_sid) {
> + if (lsmblob_is_set(&audit_sig_lsm)) {
> memcpy(sig_data->ctx, ctx, len);
> security_release_secctx(ctx, len);
> }
> diff --git a/kernel/audit.h b/kernel/audit.h
> index 958d5b8fc1b3..29e29c6f4afb 100644
> --- a/kernel/audit.h
> +++ b/kernel/audit.h
> @@ -22,6 +22,7 @@
> #include <linux/fs.h>
> #include <linux/audit.h>
> #include <linux/skbuff.h>
> +#include <linux/security.h>
> #include <uapi/linux/mqueue.h>
> #include <linux/tty.h>
>
> @@ -147,7 +148,7 @@ struct audit_context {
> kuid_t target_auid;
> kuid_t target_uid;
> unsigned int target_sessionid;
> - u32 target_sid;
> + struct lsmblob target_lsm;
> char target_comm[TASK_COMM_LEN];
>
> struct audit_tree_refs *trees, *first_trees;
> @@ -338,7 +339,7 @@ extern char *audit_unpack_string(void **bufp, size_t *remain, size_t len);
>
> extern pid_t audit_sig_pid;
> extern kuid_t audit_sig_uid;
> -extern u32 audit_sig_sid;
> +extern struct lsmblob audit_sig_lsm;
>
> extern int audit_filter(int msgtype, unsigned int listtype);
>
> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index 54797c0fc3b7..c7aa39bda5cc 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -112,7 +112,7 @@ struct audit_aux_data_pids {
> kuid_t target_auid[AUDIT_AUX_PIDS];
> kuid_t target_uid[AUDIT_AUX_PIDS];
> unsigned int target_sessionid[AUDIT_AUX_PIDS];
> - u32 target_sid[AUDIT_AUX_PIDS];
> + struct lsmblob target_lsm[AUDIT_AUX_PIDS];
> char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
> int pid_count;
> };
> @@ -938,14 +938,14 @@ static inline void audit_free_context(struct audit_context *context)
> }
>
> static int audit_log_pid_context(struct audit_context *context, pid_t pid,
> - kuid_t auid, kuid_t uid, unsigned int sessionid,
> - u32 sid, char *comm)
> + kuid_t auid, kuid_t uid,
> + unsigned int sessionid,
> + struct lsmblob *blob, char *comm)
> {
> struct audit_buffer *ab;
> char *ctx = NULL;
> u32 len;
> int rc = 0;
> - struct lsmblob blob;
>
> ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
> if (!ab)
> @@ -954,9 +954,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
> audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
> from_kuid(&init_user_ns, auid),
> from_kuid(&init_user_ns, uid), sessionid);
> - if (sid) {
> - lsmblob_init(&blob, sid);
> - if (security_secid_to_secctx(&blob, &ctx, &len)) {
> + if (lsmblob_is_set(blob)) {
> + if (security_secid_to_secctx(blob, &ctx, &len)) {
> audit_log_format(ab, " obj=(none)");
> rc = 1;
> } else {
> @@ -1527,7 +1526,7 @@ static void audit_log_exit(void)
> axs->target_auid[i],
> axs->target_uid[i],
> axs->target_sessionid[i],
> - axs->target_sid[i],
> + &axs->target_lsm[i],
> axs->target_comm[i]))
> call_panic = 1;
> }
> @@ -1536,7 +1535,7 @@ static void audit_log_exit(void)
> audit_log_pid_context(context, context->target_pid,
> context->target_auid, context->target_uid,
> context->target_sessionid,
> - context->target_sid, context->target_comm))
> + &context->target_lsm, context->target_comm))
> call_panic = 1;
>
> if (context->pwd.dentry && context->pwd.mnt) {
> @@ -1713,7 +1712,7 @@ void __audit_syscall_exit(int success, long return_code)
> context->aux = NULL;
> context->aux_pids = NULL;
> context->target_pid = 0;
> - context->target_sid = 0;
> + lsmblob_init(&context->target_lsm, 0);
> context->sockaddr_len = 0;
> context->type = 0;
> context->fds[0] = -1;
> @@ -2367,15 +2366,12 @@ int __audit_sockaddr(int len, void *a)
> void __audit_ptrace(struct task_struct *t)
> {
> struct audit_context *context = audit_context();
> - struct lsmblob blob;
>
> context->target_pid = task_tgid_nr(t);
> context->target_auid = audit_get_loginuid(t);
> context->target_uid = task_uid(t);
> context->target_sessionid = audit_get_sessionid(t);
> - security_task_getsecid(t, &blob);
> - /* scaffolding - until target_sid is converted */
> - context->target_sid = blob.secid[0];
> + security_task_getsecid(t, &context->target_lsm);
> memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
> }
>
> @@ -2392,7 +2388,6 @@ int audit_signal_info(int sig, struct task_struct *t)
> struct audit_aux_data_pids *axp;
> struct audit_context *ctx = audit_context();
> kuid_t uid = current_uid(), auid, t_uid = task_uid(t);
> - struct lsmblob blob;
>
> if (auditd_test_task(t) &&
> (sig == SIGTERM || sig == SIGHUP ||
> @@ -2403,9 +2398,7 @@ int audit_signal_info(int sig, struct task_struct *t)
> audit_sig_uid = auid;
> else
> audit_sig_uid = uid;
> - security_task_getsecid(current, &blob);
> - /* scaffolding until audit_sig_sid is converted */
> - audit_sig_sid = blob.secid[0];
> + security_task_getsecid(current, &audit_sig_lsm);
> }
>
> if (!audit_signals || audit_dummy_context())
> @@ -2418,9 +2411,7 @@ int audit_signal_info(int sig, struct task_struct *t)
> ctx->target_auid = audit_get_loginuid(t);
> ctx->target_uid = t_uid;
> ctx->target_sessionid = audit_get_sessionid(t);
> - security_task_getsecid(t, &blob);
> - /* scaffolding until target_sid is converted */
> - ctx->target_sid = blob.secid[0];
> + security_task_getsecid(t, &ctx->target_lsm);
> memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
> return 0;
> }
> @@ -2441,9 +2432,7 @@ int audit_signal_info(int sig, struct task_struct *t)
> axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
> axp->target_uid[axp->pid_count] = t_uid;
> axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
> - security_task_getsecid(t, &blob);
> - /* scaffolding until target_sid is converted */
> - axp->target_sid[axp->pid_count] = blob.secid[0];
> + security_task_getsecid(t, &axp->target_lsm[axp->pid_count]);
> memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
> axp->pid_count++;
>
> diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
> index fefa848cf0c7..1afb75a893af 100644
> --- a/security/integrity/ima/ima_main.c
> +++ b/security/integrity/ima/ima_main.c
> @@ -363,7 +363,6 @@ int ima_file_mmap(struct file *file, unsigned long prot)
> int ima_bprm_check(struct linux_binprm *bprm)
> {
> int ret;
> - u32 secid;
> struct lsmblob blob;
>
> security_task_getsecid(current, &blob);
> @@ -373,9 +372,10 @@ int ima_bprm_check(struct linux_binprm *bprm)
> if (ret)
> return ret;
>
> - security_cred_getsecid(bprm->cred, &secid);
> - return process_measurement(bprm->file, bprm->cred, secid, NULL, 0,
> - MAY_EXEC, CREDS_CHECK);
> + security_cred_getsecid(bprm->cred, &blob);
> + /* scaffolding until process_measurement changes */
> + return process_measurement(bprm->file, bprm->cred, blob.secid[0],
> + NULL, 0, MAY_EXEC, CREDS_CHECK);
> }
>
> /**
> diff --git a/security/security.c b/security/security.c
> index 91388553d3d7..3180a6f30625 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -1627,10 +1627,16 @@ void security_transfer_creds(struct cred *new, const struct cred *old)
> call_void_hook(cred_transfer, new, old);
> }
>
> -void security_cred_getsecid(const struct cred *c, u32 *secid)
> +void security_cred_getsecid(const struct cred *c, struct lsmblob *blob)
> {
> - *secid = 0;
> - call_void_hook(cred_getsecid, c, secid);
> + struct security_hook_list *hp;
> +
> + lsmblob_init(blob, 0);
> + hlist_for_each_entry(hp, &security_hook_heads.cred_getsecid, list) {
> + if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
> + continue;
> + hp->hook.cred_getsecid(c, &blob->secid[hp->lsmid->slot]);
> + }
> }
> EXPORT_SYMBOL(security_cred_getsecid);
>
>
^ permalink raw reply
* Re: [PATCH v4 14/23] IMA: Change internal interfaces to use lsmblobs
From: John Johansen @ 2019-06-26 23:58 UTC (permalink / raw)
To: Casey Schaufler, casey.schaufler, jmorris, linux-security-module,
selinux
Cc: keescook, penguin-kernel, paul, sds
In-Reply-To: <20190626192234.11725-15-casey@schaufler-ca.com>
On 6/26/19 12:22 PM, Casey Schaufler wrote:
> The IMA interfaces ima_get_action() and ima_match_policy()
> call LSM functions that use lsmblobs. Change the IMA functions
> to pass the lsmblob to be compatible with the LSM functions.
>
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: John Johansen <john.johansen@canonical.com>
> ---
> security/integrity/ima/ima.h | 10 ++++++----
> security/integrity/ima/ima_api.c | 9 +++++----
> security/integrity/ima/ima_appraise.c | 4 +---
> security/integrity/ima/ima_main.c | 27 +++++++++++----------------
> security/integrity/ima/ima_policy.c | 12 ++++++------
> 5 files changed, 29 insertions(+), 33 deletions(-)
>
> diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
> index 5a337239d9e4..73b3b15dec5c 100644
> --- a/security/integrity/ima/ima.h
> +++ b/security/integrity/ima/ima.h
> @@ -192,8 +192,9 @@ enum ima_hooks {
> };
>
> /* LIM API function definitions */
> -int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
> - int mask, enum ima_hooks func, int *pcr);
> +int ima_get_action(struct inode *inode, const struct cred *cred,
> + struct lsmblob *blob, int mask, enum ima_hooks func,
> + int *pcr);
> int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func);
> int ima_collect_measurement(struct integrity_iint_cache *iint,
> struct file *file, void *buf, loff_t size,
> @@ -213,8 +214,9 @@ void ima_free_template_entry(struct ima_template_entry *entry);
> const char *ima_d_path(const struct path *path, char **pathbuf, char *filename);
>
> /* IMA policy related functions */
> -int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
> - enum ima_hooks func, int mask, int flags, int *pcr);
> +int ima_match_policy(struct inode *inode, const struct cred *cred,
> + struct lsmblob *blob, enum ima_hooks func, int mask,
> + int flags, int *pcr);
> void ima_init_policy(void);
> void ima_update_policy(void);
> void ima_update_policy_flag(void);
> diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
> index c7505fb122d4..94b2a4840d81 100644
> --- a/security/integrity/ima/ima_api.c
> +++ b/security/integrity/ima/ima_api.c
> @@ -159,7 +159,7 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
> * ima_get_action - appraise & measure decision based on policy.
> * @inode: pointer to inode to measure
> * @cred: pointer to credentials structure to validate
> - * @secid: secid of the task being validated
> + * @blob: LSM data of the task being validated
> * @mask: contains the permission mask (MAY_READ, MAY_WRITE, MAY_EXEC,
> * MAY_APPEND)
> * @func: caller identifier
> @@ -175,14 +175,15 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
> * Returns IMA_MEASURE, IMA_APPRAISE mask.
> *
> */
> -int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
> - int mask, enum ima_hooks func, int *pcr)
> +int ima_get_action(struct inode *inode, const struct cred *cred,
> + struct lsmblob *blob, int mask, enum ima_hooks func,
> + int *pcr)
> {
> int flags = IMA_MEASURE | IMA_AUDIT | IMA_APPRAISE | IMA_HASH;
>
> flags &= ima_policy_flag;
>
> - return ima_match_policy(inode, cred, secid, func, mask, flags, pcr);
> + return ima_match_policy(inode, cred, blob, func, mask, flags, pcr);
> }
>
> /*
> diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
> index 85c7692fc4a3..3ff7aae81829 100644
> --- a/security/integrity/ima/ima_appraise.c
> +++ b/security/integrity/ima/ima_appraise.c
> @@ -50,15 +50,13 @@ bool is_ima_appraise_enabled(void)
> */
> int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func)
> {
> - u32 secid;
> struct lsmblob blob;
>
> if (!ima_appraise)
> return 0;
>
> security_task_getsecid(current, &blob);
> - lsmblob_secid(&blob, &secid);
> - return ima_match_policy(inode, current_cred(), secid, func, mask,
> + return ima_match_policy(inode, current_cred(), &blob, func, mask,
> IMA_APPRAISE | IMA_HASH, NULL);
> }
>
> diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
> index 1afb75a893af..0588dd9a88db 100644
> --- a/security/integrity/ima/ima_main.c
> +++ b/security/integrity/ima/ima_main.c
> @@ -169,8 +169,8 @@ void ima_file_free(struct file *file)
> }
>
> static int process_measurement(struct file *file, const struct cred *cred,
> - u32 secid, char *buf, loff_t size, int mask,
> - enum ima_hooks func)
> + struct lsmblob *blob, char *buf, loff_t size,
> + int mask, enum ima_hooks func)
> {
> struct inode *inode = file_inode(file);
> struct integrity_iint_cache *iint = NULL;
> @@ -192,7 +192,7 @@ static int process_measurement(struct file *file, const struct cred *cred,
> * bitmask based on the appraise/audit/measurement policy.
> * Included is the appraise submask.
> */
> - action = ima_get_action(inode, cred, secid, mask, func, &pcr);
> + action = ima_get_action(inode, cred, blob, mask, func, &pcr);
> violation_check = ((func == FILE_CHECK || func == MMAP_CHECK) &&
> (ima_policy_flag & IMA_MEASURE));
> if (!action && !violation_check)
> @@ -339,8 +339,7 @@ int ima_file_mmap(struct file *file, unsigned long prot)
>
> if (file && (prot & PROT_EXEC)) {
> security_task_getsecid(current, &blob);
> - /* scaffolding - until process_measurement changes */
> - return process_measurement(file, current_cred(), blob.secid[0],
> + return process_measurement(file, current_cred(), &blob,
> NULL, 0, MAY_EXEC, MMAP_CHECK);
> }
>
> @@ -366,16 +365,14 @@ int ima_bprm_check(struct linux_binprm *bprm)
> struct lsmblob blob;
>
> security_task_getsecid(current, &blob);
> - /* scaffolding until process_measurement changes */
> - ret = process_measurement(bprm->file, current_cred(), blob.secid[0],
> - NULL, 0, MAY_EXEC, BPRM_CHECK);
> + ret = process_measurement(bprm->file, current_cred(), &blob, NULL, 0,
> + MAY_EXEC, BPRM_CHECK);
> if (ret)
> return ret;
>
> security_cred_getsecid(bprm->cred, &blob);
> - /* scaffolding until process_measurement changes */
> - return process_measurement(bprm->file, bprm->cred, blob.secid[0],
> - NULL, 0, MAY_EXEC, CREDS_CHECK);
> + return process_measurement(bprm->file, bprm->cred, &blob, NULL, 0,
> + MAY_EXEC, CREDS_CHECK);
> }
>
> /**
> @@ -393,8 +390,7 @@ int ima_file_check(struct file *file, int mask)
> struct lsmblob blob;
>
> security_task_getsecid(current, &blob);
> - /* scaffolding until process_measurement changes */
> - return process_measurement(file, current_cred(), blob.secid[0], NULL, 0,
> + return process_measurement(file, current_cred(), &blob, NULL, 0,
> mask & (MAY_READ | MAY_WRITE | MAY_EXEC |
> MAY_APPEND), FILE_CHECK);
> }
> @@ -526,9 +522,8 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size,
>
> func = read_idmap[read_id] ?: FILE_CHECK;
> security_task_getsecid(current, &blob);
> - /* scaffolding until process_measurement changes */
> - return process_measurement(file, current_cred(), blob.secid[0], buf,
> - size, MAY_READ, func);
> + return process_measurement(file, current_cred(), &blob, buf, size,
> + MAY_READ, func);
> }
>
> /**
> diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
> index 92ee3d984c73..dbad256aa7b4 100644
> --- a/security/integrity/ima/ima_policy.c
> +++ b/security/integrity/ima/ima_policy.c
> @@ -286,7 +286,7 @@ static void ima_lsm_update_rules(void)
> * Returns true on rule match, false on failure.
> */
> static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
> - const struct cred *cred, u32 secid,
> + const struct cred *cred, struct lsmblob *blob,
> enum ima_hooks func, int mask)
> {
> int i;
> @@ -345,7 +345,6 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
> case LSM_SUBJ_USER:
> case LSM_SUBJ_ROLE:
> case LSM_SUBJ_TYPE:
> - lsmblob_init(&blob, secid);
> rc = security_filter_rule_match(&blob,
> rule->lsm[i].type,
> Audit_equal,
> @@ -394,7 +393,7 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
> * @inode: pointer to an inode for which the policy decision is being made
> * @cred: pointer to a credentials structure for which the policy decision is
> * being made
> - * @secid: LSM secid of the task to be validated
> + * @blob: LSM data of the task to be validated
> * @func: IMA hook identifier
> * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
> * @pcr: set the pcr to extend
> @@ -406,8 +405,9 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
> * list when walking it. Reads are many orders of magnitude more numerous
> * than writes so ima_match_policy() is classical RCU candidate.
> */
> -int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
> - enum ima_hooks func, int mask, int flags, int *pcr)
> +int ima_match_policy(struct inode *inode, const struct cred *cred,
> + struct lsmblob *blob, enum ima_hooks func, int mask,
> + int flags, int *pcr)
> {
> struct ima_rule_entry *entry;
> int action = 0, actmask = flags | (flags << 1);
> @@ -418,7 +418,7 @@ int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
> if (!(entry->action & actmask))
> continue;
>
> - if (!ima_match_rules(entry, inode, cred, secid, func, mask))
> + if (!ima_match_rules(entry, inode, cred, blob, func, mask))
> continue;
>
> action |= entry->flags & IMA_ACTION_FLAGS;
>
^ permalink raw reply
* Re: [PATCH V33 24/30] bpf: Restrict bpf when kernel lockdown is in confidentiality mode
From: Andy Lutomirski @ 2019-06-27 0:57 UTC (permalink / raw)
To: James Morris
Cc: Andy Lutomirski, Matthew Garrett, linux-security, LKML, Linux API,
David Howells, Alexei Starovoitov, Matthew Garrett,
Network Development, Chun-Yi Lee, Daniel Borkmann,
linux-security-module
In-Reply-To: <alpine.LRH.2.21.1906270621080.28132@namei.org>
> On Jun 26, 2019, at 1:22 PM, James Morris <jmorris@namei.org> wrote:
>
> [Adding the LSM mailing list: missed this patchset initially]
>
>> On Thu, 20 Jun 2019, Andy Lutomirski wrote:
>>
>> This patch exemplifies why I don't like this approach:
>>
>>> @@ -97,6 +97,7 @@ enum lockdown_reason {
>>> LOCKDOWN_INTEGRITY_MAX,
>>> LOCKDOWN_KCORE,
>>> LOCKDOWN_KPROBES,
>>> + LOCKDOWN_BPF,
>>> LOCKDOWN_CONFIDENTIALITY_MAX,
>>
>>> --- a/security/lockdown/lockdown.c
>>> +++ b/security/lockdown/lockdown.c
>>> @@ -33,6 +33,7 @@ static char *lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX+1] = {
>>> [LOCKDOWN_INTEGRITY_MAX] = "integrity",
>>> [LOCKDOWN_KCORE] = "/proc/kcore access",
>>> [LOCKDOWN_KPROBES] = "use of kprobes",
>>> + [LOCKDOWN_BPF] = "use of bpf",
>>> [LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality",
>>
>> The text here says "use of bpf", but what this patch is *really* doing
>> is locking down use of BPF to read kernel memory. If the details
>> change, then every LSM needs to get updated, and we risk breaking user
>> policies that are based on LSMs that offer excessively fine
>> granularity.
>
> Can you give an example of how the details might change?
>
>> I'd be more comfortable if the LSM only got to see "confidentiality"
>> or "integrity".
>
> These are not sufficient for creating a useful policy for the SELinux
> case.
>
>
I may have misunderstood, but I thought that SELinux mainly needed to allow certain privileged programs to bypass the policy. Is there a real example of what SELinux wants to do that can’t be done in the simplified model?
The think that specifically makes me uneasy about exposing all of these precise actions to LSMs is that they will get exposed to userspace in a way that forces us to treat them as stable ABIs.
^ permalink raw reply
* Re: [PATCH V34 19/29] Lock down module params that specify hardware parameters (eg. ioport)
From: Daniel Axtens @ 2019-06-27 1:49 UTC (permalink / raw)
To: Matthew Garrett, jmorris
Cc: linux-security-module, linux-kernel, linux-api, David Howells,
Alan Cox, Matthew Garrett
In-Reply-To: <20190622000358.19895-20-matthewgarrett@google.com>
Matthew Garrett <matthewgarrett@google.com> writes:
> From: David Howells <dhowells@redhat.com>
>
> Provided an annotation for module parameters that specify hardware
> parameters (such as io ports, iomem addresses, irqs, dma channels, fixed
> dma buffers and other types).
>
> Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
> Signed-off-by: David Howells <dhowells@redhat.com>
> Signed-off-by: Matthew Garrett <mjg59@google.com>
> ---
> include/linux/security.h | 1 +
> kernel/params.c | 27 ++++++++++++++++++++++-----
> security/lockdown/lockdown.c | 1 +
> 3 files changed, 24 insertions(+), 5 deletions(-)
>
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 61e3f4a62d16..88064d7f6827 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -92,6 +92,7 @@ enum lockdown_reason {
> LOCKDOWN_ACPI_TABLES,
> LOCKDOWN_PCMCIA_CIS,
> LOCKDOWN_TIOCSSERIAL,
> + LOCKDOWN_MODULE_PARAMETERS,
> LOCKDOWN_INTEGRITY_MAX,
> LOCKDOWN_CONFIDENTIALITY_MAX,
> };
> diff --git a/kernel/params.c b/kernel/params.c
> index ce89f757e6da..f94fe79e331d 100644
> --- a/kernel/params.c
> +++ b/kernel/params.c
> @@ -24,6 +24,7 @@
> #include <linux/err.h>
> #include <linux/slab.h>
> #include <linux/ctype.h>
> +#include <linux/security.h>
>
> #ifdef CONFIG_SYSFS
> /* Protects all built-in parameters, modules use their own param_lock */
> @@ -108,13 +109,19 @@ bool parameq(const char *a, const char *b)
> return parameqn(a, b, strlen(a)+1);
> }
>
> -static void param_check_unsafe(const struct kernel_param *kp)
> +static bool param_check_unsafe(const struct kernel_param *kp,
> + const char *doing)
> {
> if (kp->flags & KERNEL_PARAM_FL_UNSAFE) {
> pr_notice("Setting dangerous option %s - tainting kernel\n",
> kp->name);
> add_taint(TAINT_USER, LOCKDEP_STILL_OK);
> }
> +
> + if (kp->flags & KERNEL_PARAM_FL_HWPARAM &&
> + security_locked_down(LOCKDOWN_MODULE_PARAMETERS))
> + return false;
> + return true;
> }
Should this test occur before tainting the kernel?
Regards,
Daniel
>
> static int parse_one(char *param,
> @@ -144,8 +151,10 @@ static int parse_one(char *param,
> pr_debug("handling %s with %p\n", param,
> params[i].ops->set);
> kernel_param_lock(params[i].mod);
> - param_check_unsafe(¶ms[i]);
> - err = params[i].ops->set(val, ¶ms[i]);
> + if (param_check_unsafe(¶ms[i], doing))
> + err = params[i].ops->set(val, ¶ms[i]);
> + else
> + err = -EPERM;
> kernel_param_unlock(params[i].mod);
> return err;
> }
> @@ -553,6 +562,12 @@ static ssize_t param_attr_show(struct module_attribute *mattr,
> return count;
> }
>
> +#ifdef CONFIG_MODULES
> +#define mod_name(mod) (mod)->name
> +#else
> +#define mod_name(mod) "unknown"
> +#endif
> +
> /* sysfs always hands a nul-terminated string in buf. We rely on that. */
> static ssize_t param_attr_store(struct module_attribute *mattr,
> struct module_kobject *mk,
> @@ -565,8 +580,10 @@ static ssize_t param_attr_store(struct module_attribute *mattr,
> return -EPERM;
>
> kernel_param_lock(mk->mod);
> - param_check_unsafe(attribute->param);
> - err = attribute->param->ops->set(buf, attribute->param);
> + if (param_check_unsafe(attribute->param, mod_name(mk->mod)))
> + err = attribute->param->ops->set(buf, attribute->param);
> + else
> + err = -EPERM;
> kernel_param_unlock(mk->mod);
> if (!err)
> return len;
> diff --git a/security/lockdown/lockdown.c b/security/lockdown/lockdown.c
> index c89046dc2155..d03c4c296af7 100644
> --- a/security/lockdown/lockdown.c
> +++ b/security/lockdown/lockdown.c
> @@ -28,6 +28,7 @@ static char *lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX+1] = {
> [LOCKDOWN_ACPI_TABLES] = "modified ACPI tables",
> [LOCKDOWN_PCMCIA_CIS] = "direct PCMCIA CIS storage",
> [LOCKDOWN_TIOCSSERIAL] = "reconfiguration of serial port IO",
> + [LOCKDOWN_MODULE_PARAMETERS] = "unsafe module parameters",
> [LOCKDOWN_INTEGRITY_MAX] = "integrity",
> [LOCKDOWN_CONFIDENTIALITY_MAX] = "confidentiality",
> };
> --
> 2.22.0.410.gd8fdbe21b5-goog
^ permalink raw reply
* Re: [PATCH v4 23/23] AppArmor: Remove the exclusive flag
From: James Morris @ 2019-06-27 2:22 UTC (permalink / raw)
To: Casey Schaufler
Cc: casey.schaufler, linux-security-module, selinux, keescook,
john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190626192234.11725-24-casey@schaufler-ca.com>
On Wed, 26 Jun 2019, Casey Schaufler wrote:
> With the inclusion of the "display" process attribute
> mechanism AppArmor no longer needs to be treated as an
> "exclusive" security module. Remove the flag that indicates
> it is exclusive. Remove the stub getpeersec_dgram AppArmor
> hook as it has no effect in the single LSM case and
> interferes in the multiple LSM case.
So now if I build a kernel with SELinux and AppArmor selected, with
SELinux registered first, I now need to use apparmor=0 at the kernel
command line to preserve existing behavior (just SELinux running).
This should at least be documented.
I wonder if this will break existing users, though. Who has both
currently selected and depends on only one of them being active?
--
James Morris
<jmorris@namei.org>
^ permalink raw reply
* Re: [PATCH v4 00/23] LSM: Module stacking for AppArmor
From: James Morris @ 2019-06-27 2:41 UTC (permalink / raw)
To: Casey Schaufler
Cc: casey.schaufler, linux-security-module, selinux, Kees Cook,
John Johansen, Tetsuo Handa, Paul Moore, Stephen Smalley
In-Reply-To: <20190626192234.11725-1-casey@schaufler-ca.com>
On Wed, 26 Jun 2019, Casey Schaufler wrote:
> This patchset provides the changes required for
> the AppArmor security module to stack safely with any other.
I get a kernel oops with this patchset when running the SELinux testsuite
(binder test) with:
$ cat /sys/kernel/security/lsm
capability,yama,loadpin,safesetid,selinux,tomoyo
[ 485.357377] binder: 4224 RLIMIT_NICE not set
[ 485.360727] binder: 4224 RLIMIT_NICE not set
[ 485.361480] binder: 4224 RLIMIT_NICE not set
[ 485.362164] BUG: unable to handle kernel paging request at 0000000000001080
[ 485.362927] #PF error: [normal kernel read fault]
[ 485.363143] ------------[ cut here ]------------
[ 485.363581] PGD 800000044e17b067 P4D 800000044e17b067 PUD 44b796067 PMD 0
[ 485.364226] kernel BUG at drivers/android/binder_alloc.c:1139!
[ 485.364865] Oops: 0000 [#1] SMP PTI
[ 485.366430] CPU: 1 PID: 4224 Comm: manager Not tainted 5.1.0+ #7
[ 485.367290] Hardware name: LENOVO 20HGS3KS0S/20HGS3KS0S, BIOS N1WET44W (1.23 ) 01/24/2018
[ 485.367900] RIP: 0010:binder_alloc_do_buffer_copy+0x88/0x210
[ 485.368515] Code: 00 65 48 8b 2c 25 00 5c 01 00 41 bd 00 10 00 00 48 89
eb eb 3d 83 f8 08 0f 83 e3 00 00 00 a8 04 0f
85 45 01 00 00 85 c0 74 0e <41> 0f b6 08 88 0e a8 02 0f 85 5d 01 00 00 83
ab a8 19 00 00 01 49
[ 485.369170] RSP: 0018:ffffaf3ac1f9bb88 EFLAGS: 00010202
[ 485.369804] RAX: 0000000000000002 RBX: ffff8d3c84340000 RCX: 0000000000000000
[ 485.370470] RDX: ffff8d3c8db74cc0 RSI: ffff8d3c8b425000 RDI: ffff8d3c89844978
[ 485.371132] RBP: ffff8d3c84340000 R08: 0000000000001080 R09: 0000000000000002
[ 485.371887] R10: 0000000000000000 R11: ffff8d3c89844978 R12: 0000000000000001
[ 485.372656] R13: 0000000000001000 R14: ffff8d3c865d6300 R15: ffffffffa1a719c8
[ 485.373340] FS: 00007fae657a8680(0000) GS:ffff8d3c91480000(0000) knlGS:0000000000000000
[ 485.374017] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 485.374710] CR2: 0000000000001080 CR3: 000000044d482002 CR4: 00000000003606e0
[ 485.375423] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 485.376122] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 485.376823] Call Trace:
[ 485.377514] binder_transaction+0x371/0x2320
[ 485.378231] ? printk+0x58/0x6f
[ 485.378940] ? common_lsm_audit+0x162/0x800
[ 485.379641] ? __check_object_size+0x41/0x15d
[ 485.380347] ? binder_thread_read+0x9e4/0x1460
[ 485.381065] ? binder_update_ref_for_handle+0x83/0x1a0
[ 485.381759] binder_thread_write+0x2ae/0xfc0
[ 485.382472] ? tomoyo_path_number_perm+0x66/0x1d0
[ 485.383150] ? finish_wait+0x80/0x80
[ 485.383839] binder_ioctl+0x659/0x836
[ 485.384531] do_vfs_ioctl+0x405/0x660
[ 485.385194] ? __fput+0x157/0x230
[ 485.385850] ksys_ioctl+0x5e/0x90
[ 485.386473] __x64_sys_ioctl+0x16/0x20
[ 485.387137] do_syscall_64+0x5b/0x150
[ 485.387782] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Looks to be:
(gdb) list *(binder_alloc_do_buffer_copy + 0x88)
0xffffffff817e2cb8 is in binder_alloc_do_buffer_copy
(./include/linux/string.h:355).
350 if (q_size < size)
351 __read_overflow2();
352 }
353 if (p_size < size || q_size < size)
354 fortify_panic(__func__);
355 return __builtin_memcpy(p, q, size);
356 }
357
^ permalink raw reply
* Re: [PATCH v4 00/23] LSM: Module stacking for AppArmor
From: James Morris @ 2019-06-27 2:46 UTC (permalink / raw)
To: Casey Schaufler
Cc: casey.schaufler, linux-security-module, selinux, Kees Cook,
John Johansen, Tetsuo Handa, Paul Moore, Stephen Smalley
In-Reply-To: <alpine.LRH.2.21.1906271230490.12379@namei.org>
On Thu, 27 Jun 2019, James Morris wrote:
> On Wed, 26 Jun 2019, Casey Schaufler wrote:
>
> > This patchset provides the changes required for
> > the AppArmor security module to stack safely with any other.
>
> I get a kernel oops with this patchset when running the SELinux testsuite
> (binder test) with:
>
> $ cat /sys/kernel/security/lsm
> capability,yama,loadpin,safesetid,selinux,tomoyo
>
>
> [ 485.357377] binder: 4224 RLIMIT_NICE not set
> [ 485.360727] binder: 4224 RLIMIT_NICE not set
> [ 485.361480] binder: 4224 RLIMIT_NICE not set
> [ 485.362164] BUG: unable to handle kernel paging request at 0000000000001080
> [ 485.362927] #PF error: [normal kernel read fault]
> [ 485.363143] ------------[ cut here ]------------
> [ 485.363581] PGD 800000044e17b067 P4D 800000044e17b067 PUD 44b796067 PMD 0
> [ 485.364226] kernel BUG at drivers/android/binder_alloc.c:1139!
It's this BUG_ON:
static void binder_alloc_do_buffer_copy(struct binder_alloc *alloc,
bool to_buffer,
struct binder_buffer *buffer,
binder_size_t buffer_offset,
void *ptr,
size_t bytes)
{
/* All copies must be 32-bit aligned and 32-bit size */
BUG_ON(!check_buffer(alloc, buffer, buffer_offset, bytes));
--
James Morris
<jmorris@namei.org>
^ permalink raw reply
* Re: [PATCH v4 23/23] AppArmor: Remove the exclusive flag
From: Kees Cook @ 2019-06-27 3:28 UTC (permalink / raw)
To: James Morris
Cc: Casey Schaufler, casey.schaufler, linux-security-module, selinux,
john.johansen, penguin-kernel, paul, sds
In-Reply-To: <alpine.LRH.2.21.1906271219450.12379@namei.org>
On Thu, Jun 27, 2019 at 12:22:13PM +1000, James Morris wrote:
> On Wed, 26 Jun 2019, Casey Schaufler wrote:
>
> > With the inclusion of the "display" process attribute
> > mechanism AppArmor no longer needs to be treated as an
> > "exclusive" security module. Remove the flag that indicates
> > it is exclusive. Remove the stub getpeersec_dgram AppArmor
> > hook as it has no effect in the single LSM case and
> > interferes in the multiple LSM case.
>
> So now if I build a kernel with SELinux and AppArmor selected, with
> SELinux registered first, I now need to use apparmor=0 at the kernel
> command line to preserve existing behavior (just SELinux running).
>
> This should at least be documented.
>
> I wonder if this will break existing users, though. Who has both
> currently selected and depends on only one of them being active?
I don't think this will change a system using SELinux, right? There
would be no policy loaded for AppArmor so its hooks would be no-op.
But maybe I'm not thinking hard enough?
--
Kees Cook
^ permalink raw reply
* Re: [PATCH v4 23/23] AppArmor: Remove the exclusive flag
From: John Johansen @ 2019-06-27 3:44 UTC (permalink / raw)
To: James Morris, Casey Schaufler
Cc: casey.schaufler, linux-security-module, selinux, keescook,
penguin-kernel, paul, sds
In-Reply-To: <alpine.LRH.2.21.1906271219450.12379@namei.org>
On 6/26/19 7:22 PM, James Morris wrote:
> On Wed, 26 Jun 2019, Casey Schaufler wrote:
>
>> With the inclusion of the "display" process attribute
>> mechanism AppArmor no longer needs to be treated as an
>> "exclusive" security module. Remove the flag that indicates
>> it is exclusive. Remove the stub getpeersec_dgram AppArmor
>> hook as it has no effect in the single LSM case and
>> interferes in the multiple LSM case.
>
> So now if I build a kernel with SELinux and AppArmor selected, with
> SELinux registered first, I now need to use apparmor=0 at the kernel
> command line to preserve existing behavior (just SELinux running).
>
AppArmor can be built-in (compiled) without being on the Enabled list.
If you had apparmor in your enabled list along with selinux before,
it would attempt to enabled and fail with the message
exclusive disabled: apparmor
now it will be enabled but it does match what is documented in
the lsm enabled description
A comma-separated list of LSMs, in initialization order.
Any LSMs left off this list will be ignored. This can be
controlled at boot with the "lsm=" parameter.
what isn't documented is the exclusive behavior and it does
make sense to have which LSMs are exclusive documented somewhere.
> This should at least be documented.
>
> I wonder if this will break existing users, though. Who has both
> currently selected and depends on only one of them being active?
>
thankfully even if you had apparmor in your lsm enabled list before,
this likely isn't enough to change the system behavior. You will
also need some apparmor policy installed and enough of the
usersoace to load it. Otherwise while apparmor will be enabled it
will come up in unconfined mode.
Even the interfaces /proc/*/attr/* will default to the first
major LSM in the list (in your example selinux). Apparmor's
labeling won't be visible without a task explicitly opting in
to it.
^ permalink raw reply
* Re: [PATCH v4 00/23] LSM: Module stacking for AppArmor
From: James Morris @ 2019-06-27 3:45 UTC (permalink / raw)
To: Casey Schaufler
Cc: casey.schaufler, linux-security-module, selinux, Kees Cook,
John Johansen, Tetsuo Handa, Paul Moore, Stephen Smalley
In-Reply-To: <alpine.LRH.2.21.1906271245210.13254@namei.org>
On Thu, 27 Jun 2019, James Morris wrote:
> On Thu, 27 Jun 2019, James Morris wrote:
>
> > On Wed, 26 Jun 2019, Casey Schaufler wrote:
> >
> > > This patchset provides the changes required for
> > > the AppArmor security module to stack safely with any other.
> >
> > I get a kernel oops with this patchset when running the SELinux testsuite
> > (binder test) with:
> >
> > $ cat /sys/kernel/security/lsm
> > capability,yama,loadpin,safesetid,selinux,tomoyo
Confirming there's no oops when Tomoyo is un-selected in the kernel
config.
--
James Morris
<jmorris@namei.org>
^ permalink raw reply
* Re: [PATCH v4 23/23] AppArmor: Remove the exclusive flag
From: James Morris @ 2019-06-27 3:49 UTC (permalink / raw)
To: John Johansen
Cc: Casey Schaufler, casey.schaufler, linux-security-module, selinux,
keescook, penguin-kernel, paul, sds
In-Reply-To: <d89fbbe9-49cb-646e-6cba-7951cf835bf9@canonical.com>
On Wed, 26 Jun 2019, John Johansen wrote:
> AppArmor can be built-in (compiled) without being on the Enabled list.
> If you had apparmor in your enabled list along with selinux before,
> it would attempt to enabled and fail with the message
>
> exclusive disabled: apparmor
>
> now it will be enabled but it does match what is documented in
> the lsm enabled description
>
> A comma-separated list of LSMs, in initialization order.
> Any LSMs left off this list will be ignored. This can be
> controlled at boot with the "lsm=" parameter.
Ok -- I suspect the only people who have SELinux and AppArmor selected are
doing testing / development.
--
James Morris
<jmorris@namei.org>
^ permalink raw reply
* Re: [PATCH v4 00/23] LSM: Module stacking for AppArmor
From: Kees Cook @ 2019-06-27 3:51 UTC (permalink / raw)
To: James Morris
Cc: Casey Schaufler, casey.schaufler, linux-security-module, selinux,
John Johansen, Tetsuo Handa, Paul Moore, Stephen Smalley
In-Reply-To: <alpine.LRH.2.21.1906271245210.13254@namei.org>
On Thu, Jun 27, 2019 at 12:46:01PM +1000, James Morris wrote:
> On Thu, 27 Jun 2019, James Morris wrote:
>
> > On Wed, 26 Jun 2019, Casey Schaufler wrote:
> >
> > > This patchset provides the changes required for
> > > the AppArmor security module to stack safely with any other.
> >
> > I get a kernel oops with this patchset when running the SELinux testsuite
> > (binder test) with:
> >
> > $ cat /sys/kernel/security/lsm
> > capability,yama,loadpin,safesetid,selinux,tomoyo
> >
> >
> > [ 485.357377] binder: 4224 RLIMIT_NICE not set
> > [ 485.360727] binder: 4224 RLIMIT_NICE not set
> > [ 485.361480] binder: 4224 RLIMIT_NICE not set
> > [ 485.362164] BUG: unable to handle kernel paging request at 0000000000001080
> > [ 485.362927] #PF error: [normal kernel read fault]
> > [ 485.363143] ------------[ cut here ]------------
> > [ 485.363581] PGD 800000044e17b067 P4D 800000044e17b067 PUD 44b796067 PMD 0
> > [ 485.364226] kernel BUG at drivers/android/binder_alloc.c:1139!
>
> It's this BUG_ON:
>
> static void binder_alloc_do_buffer_copy(struct binder_alloc *alloc,
> bool to_buffer,
> struct binder_buffer *buffer,
> binder_size_t buffer_offset,
> void *ptr,
> size_t bytes)
> {
> /* All copies must be 32-bit aligned and 32-bit size */
> BUG_ON(!check_buffer(alloc, buffer, buffer_offset, bytes));
Before:
if (secctx) {
size_t buf_offset = ALIGN(tr->data_size, sizeof(void *)) +
ALIGN(tr->offsets_size, sizeof(void *)) +
ALIGN(extra_buffers_size, sizeof(void *)) -
ALIGN(secctx_sz, sizeof(u64));
t->security_ctx = (uintptr_t)t->buffer->user_data + buf_offset;
binder_alloc_copy_to_buffer(&target_proc->alloc,
t->buffer, buf_offset,
secctx, secctx_sz);
security_release_secctx(secctx, secctx_sz);
secctx = NULL;
}
After:
if (lsmctx.context) {
size_t buf_offset = ALIGN(tr->data_size, sizeof(void *)) +
ALIGN(tr->offsets_size, sizeof(void *)) +
ALIGN(extra_buffers_size, sizeof(void *)) -
ALIGN(lsmctx.len, sizeof(u64));
t->security_ctx = (uintptr_t)t->buffer->user_data + buf_offset;
binder_alloc_copy_to_buffer(&target_proc->alloc,
t->buffer, buf_offset,
lsmctx.context, lsmctx.len);
security_release_secctx(&lsmctx);
}
Which changes the "src" and "bytes" argument, assuming the size
calculation for buf_offset is the same. But, a quick shows:
- char *secctx = NULL;
- u32 secctx_sz = 0;
+ struct lsmcontext lsmctx;
...
- if (secctx) {
+ if (lsmctx.context) {
lsmctx.context isn't being initialized, and it was passed by reference,
so compiler won't complain. I'll find the patch and comment. Totally
missed it in review!
--
Kees Cook
^ permalink raw reply
* Re: [PATCH v4 17/23] LSM: Use lsmcontext in security_secid_to_secctx
From: Kees Cook @ 2019-06-27 3:53 UTC (permalink / raw)
To: Casey Schaufler
Cc: casey.schaufler, jmorris, linux-security-module, selinux,
john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190626192234.11725-18-casey@schaufler-ca.com>
On Wed, Jun 26, 2019 at 12:22:28PM -0700, Casey Schaufler wrote:
> Replace the (secctx,seclen) pointer pair with a single
> lsmcontext pointer to allow return of the LSM identifier
> along with the context and context length. This allows
> security_release_secctx() to know how to release the
> context. Callers have been modified to use or save the
> returned data from the new structure.
>
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
> ---
> drivers/android/binder.c | 24 ++++++---------
> include/linux/security.h | 4 +--
> include/net/scm.h | 9 ++----
> kernel/audit.c | 29 +++++++-----------
> kernel/auditsc.c | 31 +++++++------------
> net/ipv4/ip_sockglue.c | 7 ++---
> net/netfilter/nf_conntrack_netlink.c | 14 +++++----
> net/netfilter/nf_conntrack_standalone.c | 7 ++---
> net/netfilter/nfnetlink_queue.c | 5 +++-
> net/netlabel/netlabel_unlabeled.c | 40 ++++++++-----------------
> net/netlabel/netlabel_user.c | 7 ++---
> security/security.c | 9 ++++--
> 12 files changed, 72 insertions(+), 114 deletions(-)
>
> diff --git a/drivers/android/binder.c b/drivers/android/binder.c
> index 89e574be34cc..5d417a7b9bb3 100644
> --- a/drivers/android/binder.c
> +++ b/drivers/android/binder.c
> @@ -2874,9 +2874,7 @@ static void binder_transaction(struct binder_proc *proc,
> binder_size_t last_fixup_min_off = 0;
> struct binder_context *context = proc->context;
> int t_debug_id = atomic_inc_return(&binder_last_id);
> - char *secctx = NULL;
> - u32 secctx_sz = 0;
> - struct lsmcontext scaff; /* scaffolding */
> + struct lsmcontext lsmctx;
As James found, this needs to be zero initialized:
struct lsmcontext lsmctx = { };
otherwise...
>
> e = binder_transaction_log_add(&binder_transaction_log);
> e->debug_id = t_debug_id;
> @@ -3123,14 +3121,14 @@ static void binder_transaction(struct binder_proc *proc,
> struct lsmblob blob;
>
> security_task_getsecid(proc->tsk, &blob);
> - ret = security_secid_to_secctx(&blob, &secctx, &secctx_sz);
> + ret = security_secid_to_secctx(&blob, &lsmctx);
> if (ret) {
> return_error = BR_FAILED_REPLY;
> return_error_param = ret;
> return_error_line = __LINE__;
> goto err_get_secctx_failed;
> }
> - extra_buffers_size += ALIGN(secctx_sz, sizeof(u64));
> + extra_buffers_size += ALIGN(lsmctx.len, sizeof(u64));
> }
>
> trace_binder_transaction(reply, t, target_node);
> @@ -3149,19 +3147,17 @@ static void binder_transaction(struct binder_proc *proc,
> t->buffer = NULL;
> goto err_binder_alloc_buf_failed;
> }
> - if (secctx) {
> + if (lsmctx.context) {
This test may read stack trash.
Unless you built with the stack zeroing plugin or compiler. ;)
-Kees
> size_t buf_offset = ALIGN(tr->data_size, sizeof(void *)) +
> ALIGN(tr->offsets_size, sizeof(void *)) +
> ALIGN(extra_buffers_size, sizeof(void *)) -
> - ALIGN(secctx_sz, sizeof(u64));
> + ALIGN(lsmctx.len, sizeof(u64));
>
> t->security_ctx = (uintptr_t)t->buffer->user_data + buf_offset;
> binder_alloc_copy_to_buffer(&target_proc->alloc,
> t->buffer, buf_offset,
> - secctx, secctx_sz);
> - lsmcontext_init(&scaff, secctx, secctx_sz, 0);
> - security_release_secctx(&scaff);
> - secctx = NULL;
> + lsmctx.context, lsmctx.len);
> + security_release_secctx(&lsmctx);
> }
> t->buffer->debug_id = t->debug_id;
> t->buffer->transaction = t;
> @@ -3481,10 +3477,8 @@ static void binder_transaction(struct binder_proc *proc,
> t->buffer->transaction = NULL;
> binder_alloc_free_buf(&target_proc->alloc, t->buffer);
> err_binder_alloc_buf_failed:
> - if (secctx) {
> - lsmcontext_init(&scaff, secctx, secctx_sz, 0);
> - security_release_secctx(&scaff);
> - }
> + if (lsmctx.context)
> + security_release_secctx(&lsmctx);
> err_get_secctx_failed:
> kfree(tcomplete);
> binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 046012a7255f..7255825aa697 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -481,7 +481,7 @@ int security_setprocattr(const char *lsm, const char *name, void *value,
> size_t size);
> int security_netlink_send(struct sock *sk, struct sk_buff *skb);
> int security_ismaclabel(const char *name);
> -int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen);
> +int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp);
> int security_secctx_to_secid(const char *secdata, u32 seclen,
> struct lsmblob *blob);
> void security_release_secctx(struct lsmcontext *cp);
> @@ -1263,7 +1263,7 @@ static inline int security_ismaclabel(const char *name)
> }
>
> static inline int security_secid_to_secctx(struct lsmblob *blob,
> - char **secdata, u32 *seclen)
> + struct lsmcontext *cp)
> {
> return -EOPNOTSUPP;
> }
> diff --git a/include/net/scm.h b/include/net/scm.h
> index 6c7c3c229e4a..4a6ad8caf423 100644
> --- a/include/net/scm.h
> +++ b/include/net/scm.h
> @@ -93,17 +93,14 @@ static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
> static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
> {
> struct lsmcontext context;
> - char *secdata;
> - u32 seclen;
> int err;
>
> if (test_bit(SOCK_PASSSEC, &sock->flags)) {
> - err = security_secid_to_secctx(&scm->lsmblob, &secdata,
> - &seclen);
> + err = security_secid_to_secctx(&scm->lsmblob, &context);
>
> if (!err) {
> - put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
> - lsmcontext_init(&context, secdata, seclen, 0);/*scaffolding*/
> + put_cmsg(msg, SOL_SOCKET, SCM_SECURITY,
> + context.len, context.context);
> security_release_secctx(&context);
> }
> }
> diff --git a/kernel/audit.c b/kernel/audit.c
> index f844a2a642e6..436c23429319 100644
> --- a/kernel/audit.c
> +++ b/kernel/audit.c
> @@ -1191,9 +1191,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
> struct audit_buffer *ab;
> u16 msg_type = nlh->nlmsg_type;
> struct audit_sig_info *sig_data;
> - char *ctx = NULL;
> u32 len;
> - struct lsmcontext scaff; /* scaffolding */
> + struct lsmcontext context;
>
> err = audit_netlink_ok(skb, msg_type);
> if (err)
> @@ -1431,25 +1430,22 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
> case AUDIT_SIGNAL_INFO:
> len = 0;
> if (lsmblob_is_set(&audit_sig_lsm)) {
> - err = security_secid_to_secctx(&audit_sig_lsm, &ctx,
> - &len);
> + err = security_secid_to_secctx(&audit_sig_lsm,
> + &context);
> if (err)
> return err;
> }
> sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
> if (!sig_data) {
> - if (lsmblob_is_set(&audit_sig_lsm)) {
> - lsmcontext_init(&scaff, ctx, len, 0);
> - security_release_secctx(&scaff);
> - }
> + if (lsmblob_is_set(&audit_sig_lsm))
> + security_release_secctx(&context);
> return -ENOMEM;
> }
> sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
> sig_data->pid = audit_sig_pid;
> if (lsmblob_is_set(&audit_sig_lsm)) {
> - memcpy(sig_data->ctx, ctx, len);
> - lsmcontext_init(&scaff, ctx, len, 0);
> - security_release_secctx(&scaff);
> + memcpy(sig_data->ctx, context.context, context.len);
> + security_release_secctx(&context);
> }
> audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0,
> sig_data, sizeof(*sig_data) + len);
> @@ -2074,26 +2070,23 @@ void audit_log_key(struct audit_buffer *ab, char *key)
>
> int audit_log_task_context(struct audit_buffer *ab)
> {
> - char *ctx = NULL;
> - unsigned len;
> int error;
> struct lsmblob blob;
> - struct lsmcontext scaff; /* scaffolding */
> + struct lsmcontext context;
>
> security_task_getsecid(current, &blob);
> if (!lsmblob_is_set(&blob))
> return 0;
>
> - error = security_secid_to_secctx(&blob, &ctx, &len);
> + error = security_secid_to_secctx(&blob, &context);
> if (error) {
> if (error != -EINVAL)
> goto error_path;
> return 0;
> }
>
> - audit_log_format(ab, " subj=%s", ctx);
> - lsmcontext_init(&scaff, ctx, len, 0);
> - security_release_secctx(&scaff);
> + audit_log_format(ab, " subj=%s", context.context);
> + security_release_secctx(&context);
> return 0;
>
> error_path:
> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index 9fab0e7d90c3..0478680cd0a8 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -943,9 +943,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
> struct lsmblob *blob, char *comm)
> {
> struct audit_buffer *ab;
> - struct lsmcontext lsmcxt;
> - char *ctx = NULL;
> - u32 len;
> + struct lsmcontext lsmctx;
> int rc = 0;
>
> ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
> @@ -956,13 +954,12 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
> from_kuid(&init_user_ns, auid),
> from_kuid(&init_user_ns, uid), sessionid);
> if (lsmblob_is_set(blob)) {
> - if (security_secid_to_secctx(blob, &ctx, &len)) {
> + if (security_secid_to_secctx(blob, &lsmctx)) {
> audit_log_format(ab, " obj=(none)");
> rc = 1;
> } else {
> - audit_log_format(ab, " obj=%s", ctx);
> - lsmcontext_init(&lsmcxt, ctx, len, 0); /*scaffolding*/
> - security_release_secctx(&lsmcxt);
> + audit_log_format(ab, " obj=%s", lsmctx.context);
> + security_release_secctx(&lsmctx);
> }
> }
> audit_log_format(ab, " ocomm=");
> @@ -1174,7 +1171,6 @@ static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
>
> static void show_special(struct audit_context *context, int *call_panic)
> {
> - struct lsmcontext lsmcxt;
> struct audit_buffer *ab;
> int i;
>
> @@ -1198,17 +1194,15 @@ static void show_special(struct audit_context *context, int *call_panic)
> from_kgid(&init_user_ns, context->ipc.gid),
> context->ipc.mode);
> if (osid) {
> - char *ctx = NULL;
> - u32 len;
> + struct lsmcontext lsmcxt;
> struct lsmblob blob;
>
> lsmblob_init(&blob, osid);
> - if (security_secid_to_secctx(&blob, &ctx, &len)) {
> + if (security_secid_to_secctx(&blob, &lsmcxt)) {
> audit_log_format(ab, " osid=%u", osid);
> *call_panic = 1;
> } else {
> - audit_log_format(ab, " obj=%s", ctx);
> - lsmcontext_init(&lsmcxt, ctx, len, 0);
> + audit_log_format(ab, " obj=%s", lsmcxt.context);
> security_release_secctx(&lsmcxt);
> }
> }
> @@ -1353,20 +1347,17 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
> MAJOR(n->rdev),
> MINOR(n->rdev));
> if (n->osid != 0) {
> - char *ctx = NULL;
> - u32 len;
> struct lsmblob blob;
> - struct lsmcontext lsmcxt;
> + struct lsmcontext lsmctx;
>
> lsmblob_init(&blob, n->osid);
> - if (security_secid_to_secctx(&blob, &ctx, &len)) {
> + if (security_secid_to_secctx(&blob, &lsmctx)) {
> audit_log_format(ab, " osid=%u", n->osid);
> if (call_panic)
> *call_panic = 2;
> } else {
> - audit_log_format(ab, " obj=%s", ctx);
> - lsmcontext_init(&lsmcxt, ctx, len, 0); /* scaffolding */
> - security_release_secctx(&lsmcxt);
> + audit_log_format(ab, " obj=%s", lsmctx.context);
> + security_release_secctx(&lsmctx);
> }
> }
>
> diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
> index 7834c357b60b..80ae0c5a1301 100644
> --- a/net/ipv4/ip_sockglue.c
> +++ b/net/ipv4/ip_sockglue.c
> @@ -132,20 +132,17 @@ static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
> {
> struct lsmcontext context;
> struct lsmblob lb;
> - char *secdata;
> - u32 seclen;
> int err;
>
> err = security_socket_getpeersec_dgram(NULL, skb, &lb);
> if (err)
> return;
>
> - err = security_secid_to_secctx(&lb, &secdata, &seclen);
> + err = security_secid_to_secctx(&lb, &context);
> if (err)
> return;
>
> - put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
> - lsmcontext_init(&context, secdata, seclen, 0); /* scaffolding */
> + put_cmsg(msg, SOL_IP, SCM_SECURITY, context.len, context.context);
> security_release_secctx(&context);
> }
>
> diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
> index 6954e6600583..403307ff0fff 100644
> --- a/net/netfilter/nf_conntrack_netlink.c
> +++ b/net/netfilter/nf_conntrack_netlink.c
> @@ -328,13 +328,12 @@ static int ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
> static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
> {
> struct nlattr *nest_secctx;
> - int len, ret;
> - char *secctx;
> + int ret;
> struct lsmblob blob;
> struct lsmcontext context;
>
> lsmblob_init(&blob, ct->secmark);
> - ret = security_secid_to_secctx(&blob, &secctx, &len);
> + ret = security_secid_to_secctx(&blob, &context);
> if (ret)
> return 0;
>
> @@ -343,13 +342,12 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
> if (!nest_secctx)
> goto nla_put_failure;
>
> - if (nla_put_string(skb, CTA_SECCTX_NAME, secctx))
> + if (nla_put_string(skb, CTA_SECCTX_NAME, context.context))
> goto nla_put_failure;
> nla_nest_end(skb, nest_secctx);
>
> ret = 0;
> nla_put_failure:
> - lsmcontext_init(&context, secctx, len, 0); /* scaffolding */
> security_release_secctx(&context);
> return ret;
> }
> @@ -620,12 +618,16 @@ static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
> #ifdef CONFIG_NF_CONNTRACK_SECMARK
> int len, ret;
> struct lsmblob blob;
> + struct lsmcontext context;
>
> lsmblob_init(&blob, ct->secmark);
> - ret = security_secid_to_secctx(&blob, NULL, &len);
> + ret = security_secid_to_secctx(&blob, &context);
> if (ret)
> return 0;
>
> + len = context.len;
> + security_release_secctx(&context);
> +
> return nla_total_size(0) /* CTA_SECCTX */
> + nla_total_size(sizeof(char) * len); /* CTA_SECCTX_NAME */
> #else
> diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
> index 79158ad0486e..fcb51ab2bb8b 100644
> --- a/net/netfilter/nf_conntrack_standalone.c
> +++ b/net/netfilter/nf_conntrack_standalone.c
> @@ -173,19 +173,16 @@ static void ct_seq_stop(struct seq_file *s, void *v)
> static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
> {
> int ret;
> - u32 len;
> - char *secctx;
> struct lsmblob blob;
> struct lsmcontext context;
>
> lsmblob_init(&blob, ct->secmark);
> - ret = security_secid_to_secctx(&blob, &secctx, &len);
> + ret = security_secid_to_secctx(&blob, &context);
> if (ret)
> return;
>
> - seq_printf(s, "secctx=%s ", secctx);
> + seq_printf(s, "secctx=%s ", context.context);
>
> - lsmcontext_init(&context, secctx, len, 0); /* scaffolding */
> security_release_secctx(&context);
> }
> #else
> diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
> index fe8403ef4e89..6da00c7add5b 100644
> --- a/net/netfilter/nfnetlink_queue.c
> +++ b/net/netfilter/nfnetlink_queue.c
> @@ -310,6 +310,7 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
> u32 seclen = 0;
> #if IS_ENABLED(CONFIG_NETWORK_SECMARK)
> struct lsmblob blob;
> + struct lsmcontext context;
>
> if (!skb || !sk_fullsock(skb->sk))
> return 0;
> @@ -318,10 +319,12 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
>
> if (skb->secmark) {
> lsmblob_init(&blob, skb->secmark);
> - security_secid_to_secctx(&blob, secdata, &seclen);
> + security_secid_to_secctx(&blob, &context);
> + *secdata = context.context;
> }
>
> read_unlock_bh(&skb->sk->sk_callback_lock);
> + seclen = context.len;
> #endif
> return seclen;
> }
> diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
> index 15b1945853be..4716e0011ba5 100644
> --- a/net/netlabel/netlabel_unlabeled.c
> +++ b/net/netlabel/netlabel_unlabeled.c
> @@ -388,8 +388,6 @@ int netlbl_unlhsh_add(struct net *net,
> struct netlbl_unlhsh_iface *iface;
> struct audit_buffer *audit_buf = NULL;
> struct lsmcontext context;
> - char *secctx = NULL;
> - u32 secctx_len;
> struct lsmblob blob;
>
> if (addr_len != sizeof(struct in_addr) &&
> @@ -454,12 +452,9 @@ int netlbl_unlhsh_add(struct net *net,
> rcu_read_unlock();
> if (audit_buf != NULL) {
> lsmblob_init(&blob, secid);
> - if (security_secid_to_secctx(&blob,
> - &secctx,
> - &secctx_len) == 0) {
> - audit_log_format(audit_buf, " sec_obj=%s", secctx);
> - /* scaffolding */
> - lsmcontext_init(&context, secctx, secctx_len, 0);
> + if (security_secid_to_secctx(&blob, &context) == 0) {
> + audit_log_format(audit_buf, " sec_obj=%s",
> + context.context);
> security_release_secctx(&context);
> }
> audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
> @@ -492,8 +487,6 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
> struct audit_buffer *audit_buf;
> struct net_device *dev;
> struct lsmcontext context;
> - char *secctx;
> - u32 secctx_len;
> struct lsmblob blob;
>
> spin_lock(&netlbl_unlhsh_lock);
> @@ -517,11 +510,9 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
> if (entry != NULL)
> lsmblob_init(&blob, entry->secid);
> if (entry != NULL &&
> - security_secid_to_secctx(&blob,
> - &secctx, &secctx_len) == 0) {
> - audit_log_format(audit_buf, " sec_obj=%s", secctx);
> - /* scaffolding */
> - lsmcontext_init(&context, secctx, secctx_len, 0);
> + security_secid_to_secctx(&blob, &context) == 0) {
> + audit_log_format(audit_buf, " sec_obj=%s",
> + context.context);
> security_release_secctx(&context);
> }
> audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
> @@ -560,8 +551,6 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
> struct audit_buffer *audit_buf;
> struct net_device *dev;
> struct lsmcontext context;
> - char *secctx;
> - u32 secctx_len;
> struct lsmblob blob;
>
> spin_lock(&netlbl_unlhsh_lock);
> @@ -584,10 +573,9 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
> if (entry != NULL)
> lsmblob_init(&blob, entry->secid);
> if (entry != NULL &&
> - security_secid_to_secctx(&blob,
> - &secctx, &secctx_len) == 0) {
> - audit_log_format(audit_buf, " sec_obj=%s", secctx);
> - lsmcontext_init(&context, secctx, secctx_len, 0);
> + security_secid_to_secctx(&blob, &context) == 0) {
> + audit_log_format(audit_buf, " sec_obj=%s",
> + context.context);
> security_release_secctx(&context);
> }
> audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
> @@ -1105,8 +1093,6 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
> struct lsmcontext context;
> void *data;
> u32 secid;
> - char *secctx;
> - u32 secctx_len;
> struct lsmblob blob;
>
> data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,
> @@ -1163,15 +1149,13 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
> }
>
> lsmblob_init(&blob, secid);
> - ret_val = security_secid_to_secctx(&blob, &secctx, &secctx_len);
> + ret_val = security_secid_to_secctx(&blob, &context);
> if (ret_val != 0)
> goto list_cb_failure;
> ret_val = nla_put(cb_arg->skb,
> NLBL_UNLABEL_A_SECCTX,
> - secctx_len,
> - secctx);
> - /* scaffolding */
> - lsmcontext_init(&context, secctx, secctx_len, 0);
> + context.len,
> + context.context);
> security_release_secctx(&context);
> if (ret_val != 0)
> goto list_cb_failure;
> diff --git a/net/netlabel/netlabel_user.c b/net/netlabel/netlabel_user.c
> index 94aea4985b74..2d1307f65250 100644
> --- a/net/netlabel/netlabel_user.c
> +++ b/net/netlabel/netlabel_user.c
> @@ -99,8 +99,6 @@ struct audit_buffer *netlbl_audit_start_common(int type,
> {
> struct audit_buffer *audit_buf;
> struct lsmcontext context;
> - char *secctx;
> - u32 secctx_len;
> struct lsmblob blob;
>
> if (audit_enabled == AUDIT_OFF)
> @@ -116,9 +114,8 @@ struct audit_buffer *netlbl_audit_start_common(int type,
>
> lsmblob_init(&blob, audit_info->secid);
> if (audit_info->secid != 0 &&
> - security_secid_to_secctx(&blob, &secctx, &secctx_len) == 0) {
> - audit_log_format(audit_buf, " subj=%s", secctx);
> - lsmcontext_init(&context, secctx, secctx_len, 0);/*scaffolding*/
> + security_secid_to_secctx(&blob, &context) == 0) {
> + audit_log_format(audit_buf, " subj=%s", context.context);
> security_release_secctx(&context);
> }
>
> diff --git a/security/security.c b/security/security.c
> index 3563b1e2f8f9..97b468f6e6a9 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -2081,7 +2081,7 @@ int security_ismaclabel(const char *name)
> }
> EXPORT_SYMBOL(security_ismaclabel);
>
> -int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen)
> +int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp)
> {
> struct security_hook_list *hp;
> int *display = current->security;
> @@ -2089,10 +2089,13 @@ int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen)
> hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) {
> if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
> continue;
> - if (*display == LSMBLOB_INVALID || *display == hp->lsmid->slot)
> + if (*display == LSMBLOB_INVALID ||
> + *display == hp->lsmid->slot) {
> + cp->slot = hp->lsmid->slot;
> return hp->hook.secid_to_secctx(
> blob->secid[hp->lsmid->slot],
> - secdata, seclen);
> + &cp->context, &cp->len);
> + }
> }
> return 0;
> }
> --
> 2.20.1
>
--
Kees Cook
^ permalink raw reply
* Re: [PATCH v4 00/23] LSM: Module stacking for AppArmor
From: James Morris @ 2019-06-27 4:10 UTC (permalink / raw)
To: Casey Schaufler
Cc: casey.schaufler, linux-security-module, selinux, Kees Cook,
John Johansen, Tetsuo Handa, Paul Moore, Stephen Smalley
In-Reply-To: <alpine.LRH.2.21.1906271344480.16512@namei.org>
On Thu, 27 Jun 2019, James Morris wrote:
> Confirming there's no oops when Tomoyo is un-selected in the kernel
> config.
n/m, the problem is still there.
--
James Morris
<jmorris@namei.org>
^ permalink raw reply
* Re: [PATCH V34 09/29] kexec_file: Restrict at runtime if the kernel is locked down
From: James Morris @ 2019-06-27 4:59 UTC (permalink / raw)
To: Matthew Garrett
Cc: linux-security-module, linux-kernel, linux-api, Jiri Bohac,
David Howells, Matthew Garrett, kexec
In-Reply-To: <20190622000358.19895-10-matthewgarrett@google.com>
On Fri, 21 Jun 2019, Matthew Garrett wrote:
> From: Jiri Bohac <jbohac@suse.cz>
>
> When KEXEC_SIG is not enabled, kernel should not load images through
> kexec_file systemcall if the kernel is locked down.
This is not a criticism of the patch but a related issue which I haven't
seen discussed (apologies if it has).
If signed code is loaded into ring 0, verified by the kernel, then
executed, you still lose your secure/trusted/verified boot state. If the
currently running kernel has been runtime-compromised, any signature
verification performed by the kernel cannot be trusted.
This problem is out of scope for the lockdown threat model (which
naturally cannot include a compromised kernel), but folk should be aware
that signature-verified kexec does not provide equivalent assurance to a
full reboot on a secure-boot system.
Potential mitigations here include runtime integrity verification of the
kernel via a separate security monitor (hypervisor, SMM, TEE etc.) or some
kind of platform support for kexec verification.
--
James Morris
<jmorris@namei.org>
^ permalink raw reply
* Re: [PATCH v8 1/2] mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options
From: Michal Hocko @ 2019-06-27 6:15 UTC (permalink / raw)
To: Kees Cook
Cc: Qian Cai, Catalin Marinas, Ard Biesheuvel, Alexander Potapenko,
Andrew Morton, Christoph Lameter, Masahiro Yamada, James Morris,
Serge E. Hallyn, Nick Desaulniers, Kostya Serebryany,
Dmitry Vyukov, Sandeep Patil, Laura Abbott, Randy Dunlap,
Jann Horn, Mark Rutland, Marco Elver, linux-mm,
linux-security-module, kernel-hardening, clang-built-linux
In-Reply-To: <201906261303.020ADC9@keescook>
On Wed 26-06-19 13:23:34, Kees Cook wrote:
> On Wed, Jun 26, 2019 at 02:15:49PM -0400, Qian Cai wrote:
> > On Wed, 2019-06-26 at 14:19 +0200, Alexander Potapenko wrote:
> > > Both init_on_alloc and init_on_free default to zero, but those defaults
> > > can be overridden with CONFIG_INIT_ON_ALLOC_DEFAULT_ON and
> > > CONFIG_INIT_ON_FREE_DEFAULT_ON.
> > > [...]
> > > +static int __init early_init_on_alloc(char *buf)
> > > +{
> > > + int ret;
> > > + bool bool_result;
> > > +
> > > + if (!buf)
> > > + return -EINVAL;
> > > + ret = kstrtobool(buf, &bool_result);
> > > + if (bool_result)
> > > + static_branch_enable(&init_on_alloc);
> > > + else
> > > + static_branch_disable(&init_on_alloc);
> > > + return ret;
> > > +}
> > > +early_param("init_on_alloc", early_init_on_alloc);
> >
> > Do those really necessary need to be static keys?
> >
> > Adding either init_on_free=0 or init_on_alloc=0 to the kernel cmdline will
> > generate a warning with kernels built with clang.
> >
> > [ 0.000000] static_key_disable(): static key 'init_on_free+0x0/0x4' used
> > before call to jump_label_init()
> > [ 0.000000] WARNING: CPU: 0 PID: 0 at ./include/linux/jump_label.h:317
> > early_init_on_free+0x1c0/0x200
> > [ 0.000000] Modules linked in:
> > [ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.2.0-rc6-next-20190626+
> > #9
> > [ 0.000000] pstate: 60000089 (nZCv daIf -PAN -UAO)
>
> I think the issue here is that arm64 doesn't initialize static keys
> early enough.
This sounds familiar: http://lkml.kernel.org/r/CABXOdTd-cqHM_feAO1tvwn4Z=kM6WHKYAbDJ7LGfMvRPRPG7GA@mail.gmail.com
--
Michal Hocko
SUSE Labs
^ permalink raw reply
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