[PATCH 3.10 70/77] fs: btrfs: volumes.c: Fix for possible null pointer dereference

Greg Kroah-Hartman
2014-06-28T19:01:59Z

From: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>

commit 8321cf2596d283821acc466377c2b85bcd3422b7 upstream.

There is otherwise a risk of a possible null pointer dereference.

Was largely found by using a static code analysis program called cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/btrfs/volumes.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1628,11 +1628,12 @@ int btrfs_rm_device(struct btrfs_root *r
struct btrfs_fs_devices *fs_devices;
fs_devices = root->fs_info->fs_devices;
while (fs_devices) {
- if (fs_devices->seed == cur_devices)
+ if (fs_devices->seed == cur_devices) {
+ fs_devices->seed = cur_devices->seed;
break;
+ }
fs_devices = fs_devices->seed;
}
- fs_devices->seed = cur_devices->seed;
cur_devices->seed = NULL;
lock_chunks(root);
__btrfs_close_devices(cur_devices);