From: Vasily Averin vvs@virtuozzo.com
[ Upstream commit f4d74ef6220c1eda0875da30457bef5c7111ab06 ]
If seq_file .next function does not change position index, read after some lseek can generate unexpected output.
https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin vvs@virtuozzo.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Acked-by: Peter Oberparleiter oberpar@linux.ibm.com Cc: Al Viro viro@zeniv.linux.org.uk Cc: Davidlohr Bueso dave@stgolabs.net Cc: Ingo Molnar mingo@redhat.com Cc: Manfred Spraul manfred@colorfullife.com Cc: NeilBrown neilb@suse.com Cc: Steven Rostedt rostedt@goodmis.org Cc: Waiman Long longman@redhat.com Link: http://lkml.kernel.org/r/f65c6ee7-bd00-f910-2f8a-37cc67e4ff88@virtuozzo.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/gcov/fs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/gcov/fs.c b/kernel/gcov/fs.c index e5eb5ea7ea598..cc4ee482d3fba 100644 --- a/kernel/gcov/fs.c +++ b/kernel/gcov/fs.c @@ -108,9 +108,9 @@ static void *gcov_seq_next(struct seq_file *seq, void *data, loff_t *pos) { struct gcov_iterator *iter = data;
+ (*pos)++; if (gcov_iter_next(iter)) return NULL; - (*pos)++;
return iter; }