linux-btrfs.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH] Btrfs: Don't dereference extent_mapping if NULL
@ 2010-09-29 22:20 Roel Kluin
  0 siblings, 0 replies; only message in thread
From: Roel Kluin @ 2010-09-29 22:20 UTC (permalink / raw)
  To: Chris Mason, linux-btrfs, Andrew Morton, LKML

Don't dereference em if it's NULL or an error pointer.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
---
I just noticed this by code analysis. It wasn't tested in any way.

 fs/btrfs/inode.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index c038644..d4a37f8 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1787,7 +1787,8 @@ static int btrfs_io_failed_hook(struct bio *failed_bio,
 
 		read_lock(&em_tree->lock);
 		em = lookup_extent_mapping(em_tree, start, failrec->len);
-		if (em->start > start || em->start + em->len < start) {
+		if (em && !IS_ERR(em) && (em->start > start ||
+					em->start + em->len < start)) {
 			free_extent_map(em);
 			em = NULL;
 		}

^ permalink raw reply related	[flat|nested] only message in thread

only message in thread, other threads:[~2010-09-29 22:20 UTC | newest]

Thread overview: (only message) (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-09-29 22:20 [PATCH] Btrfs: Don't dereference extent_mapping if NULL Roel Kluin

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).