Re: [PATCH v3] btrfs: Fix memory leakage in the tree-log.c

From: Josef Bacik
Date: Wed Oct 09 2013 - 20:52:29 EST


On Wed, Oct 09, 2013 at 08:40:30PM -0300, Geyslan G. Bem wrote:
> In some cases, add_inode_ref() is returning without freeing
> the 'name' pointer.
>
> Added bail out to explicitly call kfree when necessary.
>
> Signed-off-by: Geyslan G. Bem <geyslan@xxxxxxxxx>
> ---
> fs/btrfs/tree-log.c | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
> index 79f057c..ad7cc5f 100644
> --- a/fs/btrfs/tree-log.c
> +++ b/fs/btrfs/tree-log.c
> @@ -1170,13 +1170,16 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
> if (!dir)
> dir = read_one_inode(root, parent_objectid);
> if (!dir)
> - return -ENOENT;
> + {
> + ret = -ENOENT;
> + goto bail;
> + }

Code formatting is

if () {
}

not

if ()
{
}


> } else {
> ret = ref_get_fields(eb, ref_ptr, &namelen, &name,
> &ref_index);
> }
> if (ret)
> - return ret;
> + goto bail;
>
> /* if we already have a perfect match, we're done */
> if (!inode_in_dir(root, path, btrfs_ino(dir), btrfs_ino(inode),
> @@ -1227,6 +1230,9 @@ out:
> btrfs_release_path(path);
> iput(dir);
> iput(inode);
> +bail:
> + if (name)
> + kfree(name);

kfree already does the if (name) part of this so this is redundant. Also if you
are going to do this you need to set name = NULL; after the kfree above it
otherwise we have a double free. Thanks,

Josef
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