btrfs: fix extent map use-after-free when handling missing device in read_one_chunk

Browse source

commit 1742e1c90c upstream.

Store the error code before freeing the extent_map. Though it's
reference counted structure, in that function it's the first and last
allocation so this would lead to a potential use-after-free.

The error can happen eg. when chunk is stored on a missing device and
the degraded mount option is missing.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=216721
Reported-by: eriri <1527030098@qq.com>
Fixes: adfb69af7d ("btrfs: add_missing_dev() should return the actual error")
CC: stable@vger.kernel.org # 4.9+
Signed-off-by: void0red <void0red@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

...

This commit is contained in:

void0red 2022-11-23 22:39:45 +08:00 • committed by Greg Kroah-Hartman

parent 712b093816

commit 169a4cf468

1 changed files with 2 additions and 1 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

3

fs/btrfs/volumes.c

View file