Re: [PATCH 1/2] xfs: fix memory leak in xfs_dir2_node_removename

Mark Tinguely
2013-10-02T21:04:40Z

On 10/02/13 15:32, Dave Chinner wrote:
> On Wed, Oct 02, 2013 at 07:51:11AM -0500, Mark Tinguely wrote:
>> Fix the leak of kernel memory in xfs_dir2_node_removename()
>> when xfs_dir2_leafn_remove() returns an error code.
>>
>> Found by Coverity in userspace same patch applies there also.
>>
>> Signed-off-by: Mark Tinguely<tinguely@sgi.com>
>> ---
>> v2 corrected bad return code as pointed out by Roger Willcocks.
>>
>> fs/xfs/xfs_dir2_node.c | 14 ++++++++------
>> 1 file changed, 8 insertions(+), 6 deletions(-)
>>
>> Index: b/fs/xfs/xfs_dir2_node.c
>> ===================================================================
>> --- a/fs/xfs/xfs_dir2_node.c
>> +++ b/fs/xfs/xfs_dir2_node.c
>> @@ -2105,12 +2105,12 @@ xfs_dir2_node_lookup(
>> */
>> int /* error */
>> xfs_dir2_node_removename(
>> - xfs_da_args_t *args) /* operation arguments */
>> + struct xfs_da_args *args) /* operation arguments */
>> {
>> - xfs_da_state_blk_t *blk; /* leaf block */
>> + struct xfs_da_state_blk *blk; /* leaf block */
>> int error; /* error return value */
>> int rval; /* operation return value */
>> - xfs_da_state_t *state; /* btree cursor */
>> + struct xfs_da_state *state; /* btree cursor */
>>
>> trace_xfs_dir2_node_removename(args);
>>
>> @@ -2132,9 +2132,10 @@ xfs_dir2_node_removename(
>> * Didn't find it, upper layer screwed up.
>> */
>> if (rval != EEXIST) {
>> - xfs_da_state_free(state);
>> - return rval;
>> + error = rval;
>> + goto done;
>
> Can you make this something like "out_free"? We tend to name jump
> labels according to the action that needs to be taken, like
> "out_unlock", "error_trans_cancel", etc...
>
> Also, this code is now "funky" in how it handles rval. it will do
> this:
>
> /*
> * Look up the entry we're deleting, set up the cursor.
> */
> error = xfs_da3_node_lookup_int(state,&rval);
> if (error)
> rval = error;
> /*
> * Didn't find it, upper layer screwed up.
> */
> if (rval != EEXIST) {
> error = rval;
> goto out_free;
> }
>
> That's kind funky with the reassignment of rval if there's an error.
> Better would be:
>
> /* Look up the entry we're deleting, set up the cursor. */
> error = xfs_da3_node_lookup_int(state,&rval);
> if (error)
> goto out_free;
>
> /* Didn't find it, upper layer screwed up. */
> if (rval != EEXIST) {
> error = rval;
> goto out_free;
> }
>
> Cheers,
>
> Dave.

nod.

thank

--Mark.