[PATCH v15 20/23] Audit: Add subj_LSM fields when necessary

Casey Schaufler
2020-02-22T00:06:15Z

Add record entries to identify subject data for all of the
security modules when there is more than one.

Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: netdev@vger.kernel.org
Cc: linux-audit@redhat.com
---
drivers/android/binder.c | 2 +-
include/linux/audit.h | 1 +
include/linux/security.h | 9 ++++-
include/net/scm.h | 3 +-
kernel/audit.c | 40 ++++++++++++++++++-
kernel/audit_fsnotify.c | 1 +
kernel/auditfilter.c | 1 +
kernel/auditsc.c | 10 +++--
net/ipv4/ip_sockglue.c | 2 +-
net/netfilter/nf_conntrack_netlink.c | 4 +-
net/netfilter/nf_conntrack_standalone.c | 2 +-
net/netfilter/nfnetlink_queue.c | 2 +-
net/netlabel/netlabel_unlabeled.c | 11 ++++--
net/netlabel/netlabel_user.c | 2 +-
net/xfrm/xfrm_policy.c | 2 +
net/xfrm/xfrm_state.c | 2 +
security/integrity/ima/ima_api.c | 1 +
security/integrity/integrity_audit.c | 1 +
security/security.c | 51 +++++++++++++++++++++++--
19 files changed, 124 insertions(+), 23 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index fb7a473f4270..ee6cd2106dea 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -3109,7 +3109,7 @@ static void binder_transaction(struct binder_proc *proc,
size_t added_size;

security_task_getsecid(proc->tsk, &blob);
- ret = security_secid_to_secctx(&blob, &lsmctx);
+ ret = security_secid_to_secctx(&blob, &lsmctx, LSMBLOB_DISPLAY);
if (ret) {
return_error = BR_FAILED_REPLY;
return_error_param = ret;
diff --git a/include/linux/audit.h b/include/linux/audit.h
index 8e1c759fd1ff..d4213c471801 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -163,6 +163,7 @@ extern void audit_log_path_denied(int type,
extern void audit_log_lost(const char *message);

extern int audit_log_task_context(struct audit_buffer *ab);
+extern void audit_log_task_lsms(struct audit_buffer *ab);
extern void audit_log_task_info(struct audit_buffer *ab);

extern int audit_update_lsm_rules(void);
diff --git a/include/linux/security.h b/include/linux/security.h
index 690f8d6495e5..26b598a843dd 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -178,6 +178,8 @@ struct lsmblob {
#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 */
+#define LSMBLOB_DISPLAY -4 /* Use the "display" slot */
+#define LSMBLOB_FIRST -5 /* Use the default "display" slot */

/**
* lsmblob_init - initialize an lsmblob structure.
@@ -219,6 +221,8 @@ static inline bool lsmblob_equal(struct lsmblob *bloba, struct lsmblob *blobb)
return !memcmp(bloba, blobb, sizeof(*bloba));
}

+const char *security_lsm_slot_name(int slot);
+
/* These functions are in security/commoncap.c */
extern int cap_capable(const struct cred *cred, struct user_namespace *ns,
int cap, unsigned int opts);
@@ -528,7 +532,8 @@ 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, struct lsmcontext *cp);
+int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp,
+ int display);
int security_secctx_to_secid(const char *secdata, u32 seclen,
struct lsmblob *blob);
void security_release_secctx(struct lsmcontext *cp);
@@ -1333,7 +1338,7 @@ static inline int security_ismaclabel(const char *name)
}

static inline int security_secid_to_secctx(struct lsmblob *blob,
- struct lsmcontext *cp)
+ struct lsmcontext *cp, int display)
{
return -EOPNOTSUPP;
}
diff --git a/include/net/scm.h b/include/net/scm.h
index 4a6ad8caf423..8b5a4737e1b8 100644
--- a/include/net/scm.h
+++ b/include/net/scm.h
@@ -96,7 +96,8 @@ 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->lsmblob, &context);
+ err = security_secid_to_secctx(&scm->lsmblob, &context,
+ LSMBLOB_DISPLAY);

if (!err) {
put_cmsg(msg, SOL_SOCKET, SCM_SECURITY,
diff --git a/kernel/audit.c b/kernel/audit.c
index a25097cfe623..c3a1d8d2d33c 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -393,6 +393,7 @@ static int audit_log_config_change(char *function_name, u32 new, u32 old,
if (rc)
allow_changes = 0; /* Something weird, deny request */
audit_log_format(ab, " res=%d", allow_changes);
+ audit_log_task_lsms(ab);
audit_log_end(ab);
return rc;
}
@@ -1098,6 +1099,7 @@ static void audit_log_feature_change(int which, u32 old_feature, u32 new_feature
audit_log_format(ab, " feature=%s old=%u new=%u old_lock=%u new_lock=%u res=%d",
audit_feature_names[which], !!old_feature, !!new_feature,
!!old_lock, !!new_lock, res);
+ audit_log_task_lsms(ab);
audit_log_end(ab);
}

@@ -1347,6 +1349,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
size--;
audit_log_n_untrustedstring(ab, data, size);
}
+ audit_log_task_lsms(ab);
audit_log_end(ab);
}
break;
@@ -1361,6 +1364,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
msg_type == AUDIT_ADD_RULE ?
"add_rule" : "remove_rule",
audit_enabled);
+ audit_log_task_lsms(ab);
audit_log_end(ab);
return -EPERM;
}
@@ -1374,6 +1378,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
audit_log_common_recv_msg(audit_context(), &ab,
AUDIT_CONFIG_CHANGE);
audit_log_format(ab, " op=trim res=1");
+ audit_log_task_lsms(ab);
audit_log_end(ab);
break;
case AUDIT_MAKE_EQUIV: {
@@ -1409,6 +1414,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
audit_log_format(ab, " new=");
audit_log_untrustedstring(ab, new);
audit_log_format(ab, " res=%d", !err);
+ audit_log_task_lsms(ab);
audit_log_end(ab);
kfree(old);
kfree(new);
@@ -1417,7 +1423,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
case AUDIT_SIGNAL_INFO:
if (lsmblob_is_set(&audit_sig_lsm)) {
err = security_secid_to_secctx(&audit_sig_lsm,
- &context);
+ &context, LSMBLOB_FIRST);
if (err)
return err;
}
@@ -1476,6 +1482,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
" old-log_passwd=%d new-log_passwd=%d res=%d",
old.enabled, s.enabled, old.log_passwd,
s.log_passwd, !err);
+ audit_log_task_lsms(ab);
audit_log_end(ab);
break;
}
@@ -2054,6 +2061,33 @@ void audit_log_key(struct audit_buffer *ab, char *key)
audit_log_format(ab, "(null)");
}

+void audit_log_task_lsms(struct audit_buffer *ab)
+{
+ int i;
+ const char *lsm;
+ struct lsmblob blob;
+ struct lsmcontext context;
+
+ /*
+ * Don't do anything unless there is more than one LSM
+ * with a security context to report.
+ */
+ if (security_lsm_slot_name(1) == NULL)
+ return;
+
+ security_task_getsecid(current, &blob);
+
+ for (i = 0; i < LSMBLOB_ENTRIES; i++) {
+ lsm = security_lsm_slot_name(i);
+ if (lsm == NULL)
+ break;
+ if (security_secid_to_secctx(&blob, &context, i))
+ continue;
+ audit_log_format(ab, " subj_%s=%s", lsm, context.context);
+ security_release_secctx(&context);
+ }
+}
+
int audit_log_task_context(struct audit_buffer *ab)
{
int error;
@@ -2064,7 +2098,7 @@ int audit_log_task_context(struct audit_buffer *ab)
if (!lsmblob_is_set(&blob))
return 0;

- error = security_secid_to_secctx(&blob, &context);
+ error = security_secid_to_secctx(&blob, &context, LSMBLOB_FIRST);
if (error) {
if (error != -EINVAL)
goto error_path;
@@ -2172,6 +2206,7 @@ void audit_log_path_denied(int type, const char *operation)
audit_log_format(ab, "op=%s", operation);
audit_log_task_info(ab);
audit_log_format(ab, " res=0");
+ audit_log_task_lsms(ab);
audit_log_end(ab);
}

@@ -2222,6 +2257,7 @@ static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid,
oldloginuid, loginuid, tty ? tty_name(tty) : "(none)",
oldsessionid, sessionid, !rc);
audit_put_tty(tty);
+ audit_log_task_lsms(ab);
audit_log_end(ab);
}

diff --git a/kernel/audit_fsnotify.c b/kernel/audit_fsnotify.c
index f0d243318452..7f8c4b1a2884 100644
--- a/kernel/audit_fsnotify.c
+++ b/kernel/audit_fsnotify.c
@@ -126,6 +126,7 @@ static void audit_mark_log_rule_change(struct audit_fsnotify_mark *audit_mark, c
audit_log_untrustedstring(ab, audit_mark->path);
audit_log_key(ab, rule->filterkey);
audit_log_format(ab, " list=%d res=1", rule->listnr);
+ audit_log_task_lsms(ab);
audit_log_end(ab);
}

diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index c9a46b78b932..cd19dd995120 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -1105,6 +1105,7 @@ static void audit_log_rule_change(char *action, struct audit_krule *rule, int re
audit_log_format(ab, " op=%s", action);
audit_log_key(ab, rule->filterkey);
audit_log_format(ab, " list=%d res=%d", rule->listnr, res);
+ audit_log_task_lsms(ab);
audit_log_end(ab);
}

diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index f71d8f7521be..68ae5fa843c1 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -973,7 +973,7 @@ 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, &lsmctx)) {
+ if (security_secid_to_secctx(blob, &lsmctx, LSMBLOB_FIRST)) {
audit_log_format(ab, " obj=(none)");
rc = 1;
} else {
@@ -1218,7 +1218,8 @@ static void show_special(struct audit_context *context, int *call_panic)
struct lsmblob blob;

lsmblob_init(&blob, osid);
- if (security_secid_to_secctx(&blob, &lsmcxt)) {
+ if (security_secid_to_secctx(&blob, &lsmcxt,
+ LSMBLOB_FIRST)) {
audit_log_format(ab, " osid=%u", osid);
*call_panic = 1;
} else {
@@ -1370,7 +1371,7 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
struct lsmcontext lsmctx;

lsmblob_init(&blob, n->osid);
- if (security_secid_to_secctx(&blob, &lsmctx)) {
+ if (security_secid_to_secctx(&blob, &lsmctx, LSMBLOB_FIRST)) {
audit_log_format(ab, " osid=%u", n->osid);
if (call_panic)
*call_panic = 2;
@@ -1479,6 +1480,7 @@ static void audit_log_exit(void)

audit_log_task_info(ab);
audit_log_key(ab, context->filterkey);
+ audit_log_task_lsms(ab);
audit_log_end(ab);

for (aux = context->aux; aux; aux = aux->next) {
@@ -2602,6 +2604,7 @@ void audit_core_dumps(long signr)
return;
audit_log_task(ab);
audit_log_format(ab, " sig=%ld res=1", signr);
+ audit_log_task_lsms(ab);
audit_log_end(ab);
}

@@ -2628,6 +2631,7 @@ void audit_seccomp(unsigned long syscall, long signr, int code)
audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x",
signr, syscall_get_arch(current), syscall,
in_compat_syscall(), KSTK_EIP(current), code);
+ audit_log_task_lsms(ab);
audit_log_end(ab);
}

diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 27af7a6b8780..10b418029cdd 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -138,7 +138,7 @@ static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
if (err)
return;

- err = security_secid_to_secctx(&lb, &context);
+ err = security_secid_to_secctx(&lb, &context, LSMBLOB_DISPLAY);
if (err)
return;

diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index e2e6d4bf4ac3..210aa5a84a08 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -334,7 +334,7 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
struct lsmcontext context;

lsmblob_init(&blob, ct->secmark);
- ret = security_secid_to_secctx(&blob, &context);
+ ret = security_secid_to_secctx(&blob, &context, LSMBLOB_DISPLAY);
if (ret)
return 0;

@@ -649,7 +649,7 @@ static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
struct lsmcontext context;

lsmblob_init(&blob, ct->secmark);
- ret = security_secid_to_secctx(&blob, &context);
+ ret = security_secid_to_secctx(&blob, &context, LSMBLOB_DISPLAY);
if (ret)
return 0;

diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
index 8969754d7fe9..0ff2b8300c28 100644
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -177,7 +177,7 @@ static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
struct lsmcontext context;

lsmblob_init(&blob, ct->secmark);
- ret = security_secid_to_secctx(&blob, &context);
+ ret = security_secid_to_secctx(&blob, &context, LSMBLOB_DISPLAY);
if (ret)
return;

diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index e0512e91fed9..89db320f8109 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -314,7 +314,7 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, struct lsmcontext *context)
if (skb->secmark) {
/* Any LSM might be looking for the secmark */
lsmblob_init(&blob, skb->secmark);
- security_secid_to_secctx(&blob, context);
+ security_secid_to_secctx(&blob, context, LSMBLOB_DISPLAY);
}

read_unlock_bh(&skb->sk->sk_callback_lock);
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index 3b0f07b59436..60a7665de0e3 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -436,7 +436,8 @@ int netlbl_unlhsh_add(struct net *net,
unlhsh_add_return:
rcu_read_unlock();
if (audit_buf != NULL) {
- if (security_secid_to_secctx(lsmblob, &context) == 0) {
+ if (security_secid_to_secctx(lsmblob, &context,
+ LSMBLOB_FIRST) == 0) {
audit_log_format(audit_buf, " sec_obj=%s",
context.context);
security_release_secctx(&context);
@@ -491,7 +492,8 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
if (dev != NULL)
dev_put(dev);
if (entry != NULL &&
- security_secid_to_secctx(&entry->lsmblob, &context) == 0) {
+ security_secid_to_secctx(&entry->lsmblob, &context,
+ LSMBLOB_FIRST) == 0) {
audit_log_format(audit_buf, " sec_obj=%s",
context.context);
security_release_secctx(&context);
@@ -551,7 +553,8 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
if (dev != NULL)
dev_put(dev);
if (entry != NULL &&
- security_secid_to_secctx(&entry->lsmblob, &context) == 0) {
+ security_secid_to_secctx(&entry->lsmblob, &context,
+ LSMBLOB_FIRST) == 0) {
audit_log_format(audit_buf, " sec_obj=%s",
context.context);
security_release_secctx(&context);
@@ -1122,7 +1125,7 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
lsmb = (struct lsmblob *)&addr6->lsmblob;
}

- ret_val = security_secid_to_secctx(lsmb, &context);
+ ret_val = security_secid_to_secctx(lsmb, &context, LSMBLOB_FIRST);
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 951ba0639d20..1941877fd16f 100644
--- a/net/netlabel/netlabel_user.c
+++ b/net/netlabel/netlabel_user.c
@@ -100,7 +100,7 @@ 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, &context) == 0) {
+ security_secid_to_secctx(&blob, &context, LSMBLOB_FIRST) == 0) {
audit_log_format(audit_buf, " subj=%s", context.context);
security_release_secctx(&context);
}
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index dbda08ec566e..173397c215d5 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -4213,6 +4213,7 @@ void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
xfrm_audit_helper_usrinfo(task_valid, audit_buf);
audit_log_format(audit_buf, " res=%u", result);
xfrm_audit_common_policyinfo(xp, audit_buf);
+ audit_log_task_lsms(audit_buf);
audit_log_end(audit_buf);
}
EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
@@ -4228,6 +4229,7 @@ void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
xfrm_audit_helper_usrinfo(task_valid, audit_buf);
audit_log_format(audit_buf, " res=%u", result);
xfrm_audit_common_policyinfo(xp, audit_buf);
+ audit_log_task_lsms(audit_buf);
audit_log_end(audit_buf);
}
EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 170d6e7f31d3..77f07e684429 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -2645,6 +2645,7 @@ void xfrm_audit_state_add(struct xfrm_state *x, int result, bool task_valid)
xfrm_audit_helper_usrinfo(task_valid, audit_buf);
xfrm_audit_helper_sainfo(x, audit_buf);
audit_log_format(audit_buf, " res=%u", result);
+ audit_log_task_lsms(audit_buf);
audit_log_end(audit_buf);
}
EXPORT_SYMBOL_GPL(xfrm_audit_state_add);
@@ -2659,6 +2660,7 @@ void xfrm_audit_state_delete(struct xfrm_state *x, int result, bool task_valid)
xfrm_audit_helper_usrinfo(task_valid, audit_buf);
xfrm_audit_helper_sainfo(x, audit_buf);
audit_log_format(audit_buf, " res=%u", result);
+ audit_log_task_lsms(audit_buf);
audit_log_end(audit_buf);
}
EXPORT_SYMBOL_GPL(xfrm_audit_state_delete);
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index b481bbc2e55f..7eb8784f15a4 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -365,6 +365,7 @@ void ima_audit_measurement(struct integrity_iint_cache *iint,
audit_log_format(ab, " hash=\"%s:%s\"", algo_name, hash);

audit_log_task_info(ab);
+ audit_log_task_lsms(ab);
audit_log_end(ab);

iint->flags |= IMA_AUDITED;
diff --git a/security/integrity/integrity_audit.c b/security/integrity/integrity_audit.c
index 5109173839cc..bca89ae72e3d 100644
--- a/security/integrity/integrity_audit.c
+++ b/security/integrity/integrity_audit.c
@@ -54,5 +54,6 @@ void integrity_audit_msg(int audit_msgno, struct inode *inode,
audit_log_format(ab, " ino=%lu", inode->i_ino);
}
audit_log_format(ab, " res=%d", !result);
+ audit_log_task_lsms(ab);
audit_log_end(ab);
}
diff --git a/security/security.c b/security/security.c
index d6600bb81829..a66786c255aa 100644
--- a/security/security.c
+++ b/security/security.c
@@ -480,7 +480,31 @@ static int lsm_append(const char *new, char **result)
* Pointers to the LSM id structures for local use.
*/
static int lsm_slot __lsm_ro_after_init;
-static struct lsm_id *lsm_slotlist[LSMBLOB_ENTRIES];
+static struct lsm_id *lsm_slotlist[LSMBLOB_ENTRIES] __lsm_ro_after_init;
+
+/**
+ * security_lsm_slot_name - Get the name of the security module in a slot
+ * @slot: index into the "display" slot list.
+ *
+ * Provide the name of the security module associated with
+ * a display slot.
+ *
+ * If @slot is LSMBLOB_INVALID return the value
+ * for slot 0 if it has been set, otherwise NULL.
+ *
+ * Returns a pointer to the name string or NULL.
+ */
+const char *security_lsm_slot_name(int slot)
+{
+ if (slot == LSMBLOB_INVALID)
+ slot = 0;
+ else if (slot >= LSMBLOB_ENTRIES || slot < 0)
+ return NULL;
+
+ if (lsm_slotlist[slot] == NULL)
+ return NULL;
+ return lsm_slotlist[slot]->lsm;
+}

/**
* security_add_hooks - Add a modules hooks to the hook lists.
@@ -2169,13 +2193,32 @@ int security_ismaclabel(const char *name)
}
EXPORT_SYMBOL(security_ismaclabel);

-int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp)
+int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp,
+ int display)
{
struct security_hook_list *hp;
- int display = lsm_task_display(current);

memset(cp, 0, sizeof(*cp));

+ /*
+ * display either is the slot number use for formatting
+ * or an instruction on which relative slot to use.
+ */
+ if (display == LSMBLOB_DISPLAY)
+ display = lsm_task_display(current);
+ else if (display == LSMBLOB_FIRST)
+ display = LSMBLOB_INVALID;
+ else if (display < 0) {
+ WARN_ONCE(true,
+ "LSM: security_secid_to_secctx unknown display\n");
+ display = LSMBLOB_INVALID;
+ } else if (display >= lsm_slot) {
+ WARN_ONCE(true,
+ "LSM: security_secid_to_secctx invalid display\n");
+ display = LSMBLOB_INVALID;
+ }
+
+
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;
@@ -2186,7 +2229,7 @@ int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp)
&cp->context, &cp->len);
}
}
- return 0;
+ return -EOPNOTSUPP;
}
EXPORT_SYMBOL(security_secid_to_secctx);

--
2.24.1