diff options
| author | David Howells <dhowells@redhat.com> | 2010-07-29 15:45:55 +0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-07-30 02:16:18 +0400 |
| commit | 8f92054e7ca1d3a3ae50fb42d2253ac8730d9b2a (patch) | |
| tree | 29d1bcf78bf04fe41c7e811f806f58d655c41f9f /include/linux/sched.h | |
| parent | de09a9771a5346029f4d11e4ac886be7f9bfdd75 (diff) | |
| download | linux-8f92054e7ca1d3a3ae50fb42d2253ac8730d9b2a.tar.xz | |
CRED: Fix __task_cred()'s lockdep check and banner comment
Fix __task_cred()'s lockdep check by removing the following validation
condition:
lockdep_tasklist_lock_is_held()
as commit_creds() does not take the tasklist_lock, and nor do most of the
functions that call it, so this check is pointless and it can prevent
detection of the RCU lock not being held if the tasklist_lock is held.
Instead, add the following validation condition:
task->exit_state >= 0
to permit the access if the target task is dead and therefore unable to change
its own credentials.
Fix __task_cred()'s comment to:
(1) discard the bit that says that the caller must prevent the target task
from being deleted. That shouldn't need saying.
(2) Add a comment indicating the result of __task_cred() should not be passed
directly to get_cred(), but rather than get_task_cred() should be used
instead.
Also put a note into the documentation to enforce this point there too.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux/sched.h')
| -rw-r--r-- | include/linux/sched.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index 747fcaedddb7..0478888c6899 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -214,6 +214,7 @@ extern char ___assert_task_state[1 - 2*!!( #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) +#define task_is_dead(task) ((task)->exit_state != 0) #define task_is_stopped_or_traced(task) \ ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) #define task_contributes_to_load(task) \ |