[PATCH] xfs: xfs_dabuf_map should return ENOMEM when map allocation fails

[PATCH] xfs: xfs_dabuf_map should return ENOMEM when map allocation fails

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

If the xfs_buf_map array allocation in xfs_dabuf_map fails for whatever
reason, we bail out with error code zero.  This will confuse callers, so
make sure that we return ENOMEM.  Allocation failure should never happen
with the small size of the array, but code defensively anyway.

Fixes: 45feef8f50b94d ("xfs: refactor xfs_dabuf_map")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/libxfs/xfs_da_btree.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/libxfs/xfs_da_btree.c b/fs/xfs/libxfs/xfs_da_btree.c
index a7880c6285db..897749c41f36 100644
--- a/fs/xfs/libxfs/xfs_da_btree.c
+++ b/fs/xfs/libxfs/xfs_da_btree.c
@@ -2521,8 +2521,10 @@ xfs_dabuf_map(
 	 */
 	if (nirecs > 1) {
 		map = kmem_zalloc(nirecs * sizeof(struct xfs_buf_map), KM_NOFS);
-		if (!map)
+		if (!map) {
+			error = -ENOMEM;
 			goto out_free_irecs;
+		}
 		*mapp = map;
 	}
 

Re: [PATCH] xfs: xfs_dabuf_map should return ENOMEM when map allocation fails

[Christoph Hellwig]

On Sat, Mar 14, 2020 at 10:29:13AM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> If the xfs_buf_map array allocation in xfs_dabuf_map fails for whatever
> reason, we bail out with error code zero.  This will confuse callers, so
> make sure that we return ENOMEM.  Allocation failure should never happen
> with the small size of the array, but code defensively anyway.
> 
> Fixes: 45feef8f50b94d ("xfs: refactor xfs_dabuf_map")
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>

Re: [PATCH] xfs: xfs_dabuf_map should return ENOMEM when map allocation fails

[Chaitanya Kulkarni]

I've verified the commit "45feef8f50b94d56d6a433ad5baf5cdf58e3db98",
which was adds goto statement and it make sense to set error to
-ENOMEM when kmem_zalloc() fails.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

On 03/14/2020 06:44 PM, Darrick J. Wong wrote:
> From: Darrick J. Wong<darrick.wong@oracle.com>
>
> If the xfs_buf_map array allocation in xfs_dabuf_map fails for whatever
> reason, we bail out with error code zero.  This will confuse callers, so
> make sure that we return ENOMEM.  Allocation failure should never happen
> with the small size of the array, but code defensively anyway.
>
> Fixes: 45feef8f50b94d ("xfs: refactor xfs_dabuf_map")
> Signed-off-by: Darrick J. Wong<darrick.wong@oracle.com>
> ---