From: Wilfred Mallawa <wilfred.mallawa@wdc.com>

Currently, the 0th index of the zi_used_bucket_bitmap array is not freed
on error due to the pre-decrement then evaluate semantic of the while
loop used in xfs_alloc_zone_info(). Fix it by allowing for the i == 0
case to be covered.

Fixes: 080d01c41d44 ("xfs: implement zoned garbage collection")
Cc: stable@vger.kernel.org
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
---
 fs/xfs/xfs_zone_alloc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_zone_alloc.c b/fs/xfs/xfs_zone_alloc.c
index a851b98143c0..c64f9ab743a6 100644
--- a/fs/xfs/xfs_zone_alloc.c
+++ b/fs/xfs/xfs_zone_alloc.c
@@ -1217,7 +1217,7 @@ xfs_alloc_zone_info(
 	return zi;
 
 out_free_bitmaps:
-	while (--i > 0)
+	while (--i >= 0)
 		kvfree(zi->zi_used_bucket_bitmap[i]);
 	kfree(zi);
 	return NULL;
-- 
2.53.0

On Wed, 15 Apr 2026 09:45:14 +1000, Wilfred Mallawa wrote:
> Currently, the 0th index of the zi_used_bucket_bitmap array is not freed
> on error due to the pre-decrement then evaluate semantic of the while
> loop used in xfs_alloc_zone_info(). Fix it by allowing for the i == 0
> case to be covered.
> 
> 

Applied to for-next, thanks!

[1/1] xfs: fix memory leak on error in xfs_alloc_zone_info()
      commit: 592975da8c3ca87b043077e6eafa37665eae7936

Best regards,
-- 
Carlos Maiolino <cem@kernel.org>

On 15/04/2026 01:46, Wilfred Mallawa wrote:
> From: Wilfred Mallawa <wilfred.mallawa@wdc.com>
> 
> Currently, the 0th index of the zi_used_bucket_bitmap array is not freed
> on error due to the pre-decrement then evaluate semantic of the while
> loop used in xfs_alloc_zone_info(). Fix it by allowing for the i == 0
> case to be covered.
> 
> Fixes: 080d01c41d44 ("xfs: implement zoned garbage collection")
> Cc: stable@vger.kernel.org
> Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
> Signed-off-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
> ---
>  fs/xfs/xfs_zone_alloc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/xfs/xfs_zone_alloc.c b/fs/xfs/xfs_zone_alloc.c
> index a851b98143c0..c64f9ab743a6 100644
> --- a/fs/xfs/xfs_zone_alloc.c
> +++ b/fs/xfs/xfs_zone_alloc.c
> @@ -1217,7 +1217,7 @@ xfs_alloc_zone_info(
>  	return zi;
>  
>  out_free_bitmaps:
> -	while (--i > 0)
> +	while (--i >= 0)
>  		kvfree(zi->zi_used_bucket_bitmap[i]);
>  	kfree(zi);
>  	return NULL;

Thanks!

Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com>

Looks good:

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

On Wed, Apr 15, 2026 at 09:45:14AM +1000, Wilfred Mallawa wrote:
> From: Wilfred Mallawa <wilfred.mallawa@wdc.com>
> 
> Currently, the 0th index of the zi_used_bucket_bitmap array is not freed
> on error due to the pre-decrement then evaluate semantic of the while
> loop used in xfs_alloc_zone_info(). Fix it by allowing for the i == 0
> case to be covered.
> 
> Fixes: 080d01c41d44 ("xfs: implement zoned garbage collection")
> Cc: stable@vger.kernel.org

Cc: <stable@vger.kernel.org> # v6.15

(autobackport plz, I need all the help I can get)

> Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
> Signed-off-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
> ---
>  fs/xfs/xfs_zone_alloc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/xfs/xfs_zone_alloc.c b/fs/xfs/xfs_zone_alloc.c
> index a851b98143c0..c64f9ab743a6 100644
> --- a/fs/xfs/xfs_zone_alloc.c
> +++ b/fs/xfs/xfs_zone_alloc.c
> @@ -1217,7 +1217,7 @@ xfs_alloc_zone_info(
>  	return zi;
>  
>  out_free_bitmaps:
> -	while (--i > 0)
> +	while (--i >= 0)

With the git trailer amended,
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>

--D

>  		kvfree(zi->zi_used_bucket_bitmap[i]);
>  	kfree(zi);
>  	return NULL;
> -- 
> 2.53.0
> 
>