[PATCH 06/43] userns: Use cred->user_ns instead of cred->user->user_ns

"Eric W. Beiderman
2012-04-08T05:20:06Z

From: Eric W. Biederman <ebiederm@xmission.com>

Optimize performance and prepare for the removal of the user_ns reference
from user_struct. Remove the slow long walk through cred->user->user_ns and
instead go straight to cred->user_ns.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
---
fs/ecryptfs/messaging.c | 2 +-
ipc/namespace.c | 2 +-
kernel/ptrace.c | 4 ++--
kernel/sched/core.c | 2 +-
kernel/signal.c | 4 ++--
kernel/sys.c | 8 ++++----
kernel/user_namespace.c | 4 ++--
kernel/utsname.c | 2 +-
security/commoncap.c | 14 +++++++-------
security/keys/key.c | 2 +-
security/keys/permission.c | 2 +-
security/keys/process_keys.c | 2 +-
12 files changed, 24 insertions(+), 24 deletions(-)

diff --git a/fs/ecryptfs/messaging.c b/fs/ecryptfs/messaging.c
index ab22480..a750f95 100644
--- a/fs/ecryptfs/messaging.c
+++ b/fs/ecryptfs/messaging.c
@@ -303,7 +303,7 @@ int ecryptfs_process_response(struct ecryptfs_message *msg, uid_t euid,
mutex_unlock(&ecryptfs_daemon_hash_mux);
goto wake_up;
}
- tsk_user_ns = __task_cred(msg_ctx->task)->user->user_ns;
+ tsk_user_ns = __task_cred(msg_ctx->task)->user_ns;
ctx_euid = task_euid(msg_ctx->task);
rc = ecryptfs_find_daemon_by_euid(&daemon, ctx_euid, tsk_user_ns);
rcu_read_unlock();
diff --git a/ipc/namespace.c b/ipc/namespace.c
index ce0a647..f362298c 100644
--- a/ipc/namespace.c
+++ b/ipc/namespace.c
@@ -46,7 +46,7 @@ static struct ipc_namespace *create_ipc_ns(struct task_struct *tsk,
ipcns_notify(IPCNS_CREATED);
register_ipcns_notifier(ns);

- ns->user_ns = get_user_ns(task_cred_xxx(tsk, user)->user_ns);
+ ns->user_ns = get_user_ns(task_cred_xxx(tsk, user_ns));

return ns;
}
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index ee8d49b..24e0a5a 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -198,7 +198,7 @@ int __ptrace_may_access(struct task_struct *task, unsigned int mode)
return 0;
rcu_read_lock();
tcred = __task_cred(task);
- if (cred->user->user_ns == tcred->user->user_ns &&
+ if (cred->user_ns == tcred->user_ns &&
(cred->uid == tcred->euid &&
cred->uid == tcred->suid &&
cred->uid == tcred->uid &&
@@ -206,7 +206,7 @@ int __ptrace_may_access(struct task_struct *task, unsigned int mode)
cred->gid == tcred->sgid &&
cred->gid == tcred->gid))
goto ok;
- if (ptrace_has_cap(tcred->user->user_ns, mode))
+ if (ptrace_has_cap(tcred->user_ns, mode))
goto ok;
rcu_read_unlock();
return -EPERM;
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 4603b9d..96bff85 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4042,7 +4042,7 @@ static bool check_same_owner(struct task_struct *p)

rcu_read_lock();
pcred = __task_cred(p);
- if (cred->user->user_ns == pcred->user->user_ns)
+ if (cred->user_ns == pcred->user_ns)
match = (cred->euid == pcred->euid ||
cred->euid == pcred->uid);
else
diff --git a/kernel/signal.c b/kernel/signal.c
index 17afcaf..e2c5d84 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -767,14 +767,14 @@ static int kill_ok_by_cred(struct task_struct *t)
const struct cred *cred = current_cred();
const struct cred *tcred = __task_cred(t);

- if (cred->user->user_ns == tcred->user->user_ns &&
+ if (cred->user_ns == tcred->user_ns &&
(cred->euid == tcred->suid ||
cred->euid == tcred->uid ||
cred->uid == tcred->suid ||
cred->uid == tcred->uid))
return 1;

- if (ns_capable(tcred->user->user_ns, CAP_KILL))
+ if (ns_capable(tcred->user_ns, CAP_KILL))
return 1;

return 0;
diff --git a/kernel/sys.c b/kernel/sys.c
index f7a4351..82d8714 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -133,11 +133,11 @@ static bool set_one_prio_perm(struct task_struct *p)
{
const struct cred *cred = current_cred(), *pcred = __task_cred(p);

- if (pcred->user->user_ns == cred->user->user_ns &&
+ if (pcred->user_ns == cred->user_ns &&
(pcred->uid == cred->euid ||
pcred->euid == cred->euid))
return true;
- if (ns_capable(pcred->user->user_ns, CAP_SYS_NICE))
+ if (ns_capable(pcred->user_ns, CAP_SYS_NICE))
return true;
return false;
}
@@ -1498,7 +1498,7 @@ static int check_prlimit_permission(struct task_struct *task)
return 0;

tcred = __task_cred(task);
- if (cred->user->user_ns == tcred->user->user_ns &&
+ if (cred->user_ns == tcred->user_ns &&
(cred->uid == tcred->euid &&
cred->uid == tcred->suid &&
cred->uid == tcred->uid &&
@@ -1506,7 +1506,7 @@ static int check_prlimit_permission(struct task_struct *task)
cred->gid == tcred->sgid &&
cred->gid == tcred->gid))
return 0;
- if (ns_capable(tcred->user->user_ns, CAP_SYS_RESOURCE))
+ if (ns_capable(tcred->user_ns, CAP_SYS_RESOURCE))
return 0;

return -EPERM;
diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
index 3b906e9..f084083 100644
--- a/kernel/user_namespace.c
+++ b/kernel/user_namespace.c
@@ -90,7 +90,7 @@ uid_t user_ns_map_uid(struct user_namespace *to, const struct cred *cred, uid_t
{
struct user_namespace *tmp;

- if (likely(to == cred->user->user_ns))
+ if (likely(to == cred->user_ns))
return uid;

@@ -112,7 +112,7 @@ gid_t user_ns_map_gid(struct user_namespace *to, const struct cred *cred, gid_t
{
struct user_namespace *tmp;

- if (likely(to == cred->user->user_ns))
+ if (likely(to == cred->user_ns))
return gid;

/* Is cred->user the creator of the target user_ns
diff --git a/kernel/utsname.c b/kernel/utsname.c
index 405caf9..679d97a 100644
--- a/kernel/utsname.c
+++ b/kernel/utsname.c
@@ -43,7 +43,7 @@ static struct uts_namespace *clone_uts_ns(struct task_struct *tsk,

down_read(&uts_sem);
memcpy(&ns->name, &old_ns->name, sizeof(ns->name));
- ns->user_ns = get_user_ns(task_cred_xxx(tsk, user)->user_ns);
+ ns->user_ns = get_user_ns(task_cred_xxx(tsk, user_ns));
up_read(&uts_sem);
return ns;
}
diff --git a/security/commoncap.c b/security/commoncap.c
index 0cf4b53..8b3e10e 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -81,7 +81,7 @@ int cap_capable(const struct cred *cred, struct user_namespace *targ_ns,
return 0;

/* Do we have the necessary capabilities? */
- if (targ_ns == cred->user->user_ns)
+ if (targ_ns == cred->user_ns)
return cap_raised(cred->cap_effective, cap) ? 0 : -EPERM;

/* Have we tried all of the parent namespaces? */
@@ -136,10 +136,10 @@ int cap_ptrace_access_check(struct task_struct *child, unsigned int mode)
rcu_read_lock();
cred = current_cred();
child_cred = __task_cred(child);
- if (cred->user->user_ns == child_cred->user->user_ns &&
+ if (cred->user_ns == child_cred->user_ns &&
cap_issubset(child_cred->cap_permitted, cred->cap_permitted))
goto out;
- if (ns_capable(child_cred->user->user_ns, CAP_SYS_PTRACE))
+ if (ns_capable(child_cred->user_ns, CAP_SYS_PTRACE))
goto out;
ret = -EPERM;
out:
@@ -168,10 +168,10 @@ int cap_ptrace_traceme(struct task_struct *parent)
rcu_read_lock();
cred = __task_cred(parent);
child_cred = current_cred();
- if (cred->user->user_ns == child_cred->user->user_ns &&
+ if (cred->user_ns == child_cred->user_ns &&
cap_issubset(child_cred->cap_permitted, cred->cap_permitted))
goto out;
- if (has_ns_capability(parent, child_cred->user->user_ns, CAP_SYS_PTRACE))
+ if (has_ns_capability(parent, child_cred->user_ns, CAP_SYS_PTRACE))
goto out;
ret = -EPERM;
out:
@@ -214,7 +214,7 @@ static inline int cap_inh_is_capped(void)
/* they are so limited unless the current task has the CAP_SETPCAP
* capability
*/
- if (cap_capable(current_cred(), current_cred()->user->user_ns,
+ if (cap_capable(current_cred(), current_cred()->user_ns,
CAP_SETPCAP, SECURITY_CAP_AUDIT) == 0)
return 0;
return 1;
@@ -866,7 +866,7 @@ int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3,
|| ((new->securebits & SECURE_ALL_LOCKS & ~arg2)) /*[2]*/
|| (arg2 & ~(SECURE_ALL_LOCKS | SECURE_ALL_BITS)) /*[3]*/
|| (cap_capable(current_cred(),
- current_cred()->user->user_ns, CAP_SETPCAP,
+ current_cred()->user_ns, CAP_SETPCAP,
SECURITY_CAP_AUDIT) != 0) /*[4]*/
/*
* [1] no changing of bits that are locked
diff --git a/security/keys/key.c b/security/keys/key.c
index 06783cf..7e60347 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -253,7 +253,7 @@ struct key *key_alloc(struct key_type *type, const char *desc,
quotalen = desclen + type->def_datalen;

/* get hold of the key tracking for this user */
- user = key_user_lookup(uid, cred->user->user_ns);
+ user = key_user_lookup(uid, cred->user_ns);
if (!user)
goto no_memory_1;

diff --git a/security/keys/permission.c b/security/keys/permission.c
index c35b522..e146cbd 100644
--- a/security/keys/permission.c
+++ b/security/keys/permission.c
@@ -36,7 +36,7 @@ int key_task_permission(const key_ref_t key_ref, const struct cred *cred,

key = key_ref_to_ptr(key_ref);

- if (key->user->user_ns != cred->user->user_ns)
+ if (key->user->user_ns != cred->user_ns)
goto use_other_perms;

/* use the second 8-bits of permissions for keys the caller owns */
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
index be7ecb2..70febff 100644
--- a/security/keys/process_keys.c
+++ b/security/keys/process_keys.c
@@ -858,7 +858,7 @@ void key_replace_session_keyring(void)
new-> sgid = old-> sgid;
new->fsgid = old->fsgid;
new->user = get_uid(old->user);
- new->user_ns = new->user->user_ns;
+ new->user_ns = new->user_ns;
new->group_info = get_group_info(old->group_info);

new->securebits = old->securebits;
--
1.7.2.5