diff options
| author | Konstantin Khorenko <khorenko@virtuozzo.com> | 2018-06-08 17:27:11 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-10-03 16:59:16 -0700 |
| commit | 5f2391032c06f71ced9b6cf15226368c50b8a99c (patch) | |
| tree | 27c6b0f22141a053fbe01a474254f949c70d4c7c /fs | |
| parent | 00b438869cbe414d9a92419dcf702a0a74b679c5 (diff) | |
fs/lock: skip lock owner pid translation in case we are in init_pid_ns
[ Upstream commit 826d7bc9f013d01e92997883d2fd0c25f4af1f1c ]
If the flock owner process is dead and its pid has been already freed,
pid translation won't work, but we still want to show flock owner pid
number when expecting /proc/$PID/fdinfo/$FD in init pidns.
Reproducer:
process A process A1 process A2
fork()--------->
exit() open()
flock()
fork()--------->
exit() sleep()
Before the patch:
================
(root@vz7)/: cat /proc/${PID_A2}/fdinfo/3
pos: 4
flags: 02100002
mnt_id: 257
lock: (root@vz7)/:
After the patch:
===============
(root@vz7)/:cat /proc/${PID_A2}/fdinfo/3
pos: 4
flags: 02100002
mnt_id: 295
lock: 1: FLOCK ADVISORY WRITE ${PID_A1} b6:f8a61:529946 0 EOF
Fixes: 9d5b86ac13c5 ("fs/locks: Remove fl_nspid and use fs-specific l_pid for remote locks")
Signed-off-by: Konstantin Khorenko <khorenko@virtuozzo.com>
Acked-by: Andrey Vagin <avagin@openvz.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/locks.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/fs/locks.c b/fs/locks.c index db7b6917d9c5..fafce5a8d74f 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -2072,6 +2072,13 @@ static pid_t locks_translate_pid(struct file_lock *fl, struct pid_namespace *ns) return -1; if (IS_REMOTELCK(fl)) return fl->fl_pid; + /* + * If the flock owner process is dead and its pid has been already + * freed, the translation below won't work, but we still want to show + * flock owner pid number in init pidns. + */ + if (ns == &init_pid_ns) + return (pid_t)fl->fl_pid; rcu_read_lock(); pid = find_pid_ns(fl->fl_pid, &init_pid_ns); |