[34/35] kernel/gcov/fs.c: gcov_seq_next() should increase position index

Commit Message

Andrew Morton April 10, 2020, 9:34 p.m. UTC

From: Vasily Averin <[e-mail]>
Subject: kernel/gcov/fs.c: gcov_seq_next() should increase position index

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
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Vasily Averin <[e-mail]>
Acked-by: Peter Oberparleiter <[e-mail]>
Cc: Al Viro <[e-mail]>
Cc: Davidlohr Bueso <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Manfred Spraul <[e-mail]>
Cc: NeilBrown <[e-mail]>
Cc: Steven Rostedt <[e-mail]>
Cc: Waiman Long <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 kernel/gcov/fs.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Patch

--- a/kernel/gcov/fs.c~gcov_seq_next-should-increase-position-index
+++ a/kernel/gcov/fs.c
@@ -108,9 +108,9 @@  static void *gcov_seq_next(struct seq_fi
 {
 	struct gcov_iterator *iter = data;
 
+	(*pos)++;
 	if (gcov_iter_next(iter))
 		return NULL;
-	(*pos)++;
 
 	return iter;
 }