diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2009-12-09 17:19:31 +0300 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2010-10-30 16:45:25 +0400 |
| commit | 3c80fe4ac9cfb13b1bfa4edf1544e8b656716694 (patch) | |
| tree | c605435b642323cd76eea9567a43d8c67b9c9db1 /include | |
| parent | f7a998a9491f2da1d3e44d150aa611d10093da4f (diff) | |
| download | linux-3c80fe4ac9cfb13b1bfa4edf1544e8b656716694.tar.xz | |
audit: Call tty_audit_push_task() outside preempt disabled
While auditing all tasklist_lock read_lock sites I stumbled over the
following call chain:
audit_prepare_user_tty()
read_lock(&tasklist_lock);
tty_audit_push_task();
mutex_lock(&buf->mutex);
--> buf->mutex is locked with preemption disabled.
Solve this by acquiring a reference to the task struct under
rcu_read_lock and call tty_audit_push_task outside of the preempt
disabled region.
Move all code which needs to be protected by sighand lock into
tty_audit_push_task() and use lock/unlock_sighand as we do not hold
tasklist_lock.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/tty.h | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/include/linux/tty.h b/include/linux/tty.h index e500171c745f..2a754748dd5f 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -541,8 +541,8 @@ extern void tty_audit_exit(void); extern void tty_audit_fork(struct signal_struct *sig); extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); extern void tty_audit_push(struct tty_struct *tty); -extern void tty_audit_push_task(struct task_struct *tsk, - uid_t loginuid, u32 sessionid); +extern int tty_audit_push_task(struct task_struct *tsk, + uid_t loginuid, u32 sessionid); #else static inline void tty_audit_add_data(struct tty_struct *tty, unsigned char *data, size_t size) @@ -560,9 +560,10 @@ static inline void tty_audit_fork(struct signal_struct *sig) static inline void tty_audit_push(struct tty_struct *tty) { } -static inline void tty_audit_push_task(struct task_struct *tsk, - uid_t loginuid, u32 sessionid) +static inline int tty_audit_push_task(struct task_struct *tsk, + uid_t loginuid, u32 sessionid) { + return 0; } #endif |