]> git.proxmox.com Git - mirror_ubuntu-kernels.git/commit
btrfs: Don't pass NULL ptr to func that may deref it.
authorJesper Juhl <jj@chaosbits.net>
Sat, 25 Dec 2010 21:22:30 +0000 (21:22 +0000)
committerChris Mason <chris.mason@oracle.com>
Sun, 16 Jan 2011 16:30:20 +0000 (11:30 -0500)
commitff175d57f057f77d2d3031d674c2af9167a4af02
treeff04961d44566d7abc3ea4aab888900d40561c3e
parent20b450773d17e325190c158e10bfdb25dc21d2d6
btrfs: Don't pass NULL ptr to func that may deref it.

Hi,

In fs/btrfs/inode.c::fixup_tree_root_location() we have this code:

...
  if (!path) {
  err = -ENOMEM;
  goto out;
  }
...
  out:
  btrfs_free_path(path);
  return err;

btrfs_free_path() passes its argument on to other functions and some of
them end up dereferencing the pointer.
In the code above that pointer is clearly NULL, so btrfs_free_path() will
eventually cause a NULL dereference.

There are many ways to cut this cake (fix the bug). The one I chose was to
make btrfs_free_path() deal gracefully with NULL pointers. If you
disagree, feel free to come up with an alternative patch.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
fs/btrfs/ctree.c