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| author | Vasily Averin <vvs@virtuozzo.com> | 2020-01-30 13:34:49 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-04-01 11:01:50 +0200 |
| commit | b51274fabedc56adfdddbf4fce0e8fb69c7166b5 (patch) | |
| tree | 24ca7ed3ae65033449eb0c500f707c95dcc83df8 /kernel/cgroup | |
| parent | 74f554af848d8ac61454922392bc7f2153d252ee (diff) | |
| download | linux-stable-b51274fabedc56adfdddbf4fce0e8fb69c7166b5.tar.gz linux-stable-b51274fabedc56adfdddbf4fce0e8fb69c7166b5.tar.bz2 linux-stable-b51274fabedc56adfdddbf4fce0e8fb69c7166b5.zip | |
cgroup-v1: cgroup_pidlist_next should update position index
[ Upstream commit db8dd9697238be70a6b4f9d0284cd89f59c0e070 ]
if seq_file .next fuction does not change position index,
read after some lseek can generate unexpected output.
# mount | grep cgroup
# dd if=/mnt/cgroup.procs bs=1 # normal output
...
1294
1295
1296
1304
1382
584+0 records in
584+0 records out
584 bytes copied
dd: /mnt/cgroup.procs: cannot skip to specified offset
83 <<< generates end of last line
1383 <<< ... and whole last line once again
0+1 records in
0+1 records out
8 bytes copied
dd: /mnt/cgroup.procs: cannot skip to specified offset
1386 <<< generates last line anyway
0+1 records in
0+1 records out
5 bytes copied
https://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel/cgroup')
| -rw-r--r-- | kernel/cgroup/cgroup-v1.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c index 7f83f4121d8d..2db582706ec5 100644 --- a/kernel/cgroup/cgroup-v1.c +++ b/kernel/cgroup/cgroup-v1.c @@ -473,6 +473,7 @@ static void *cgroup_pidlist_next(struct seq_file *s, void *v, loff_t *pos) */ p++; if (p >= end) { + (*pos)++; return NULL; } else { *pos = *p; |