[PATCH] lib/scatterlist: fix memory leak with scsi-mq

[PATCH] lib/scatterlist: fix memory leak with scsi-mq

[Tony Battersby]

Fix a memory leak with scsi-mq triggered by commands with large data
transfer length.

Fixes: c53c6d6a68b1 ("scatterlist: allow chaining to preallocated chunks")
Cc: <stable@vger.kernel.org> # 3.17.x
Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
---

For inclusion in 3.18 and 3.17.x.

--- a/lib/scatterlist.c	2014-10-23 13:32:27.000000000 -0400
+++ b/lib/scatterlist.c	2014-10-23 13:32:36.000000000 -0400
@@ -203,10 +203,10 @@ void __sg_free_table(struct sg_table *ta
 		}
 
 		table->orig_nents -= sg_size;
-		if (!skip_first_chunk) {
-			free_fn(sgl, alloc_size);
+		if (skip_first_chunk)
 			skip_first_chunk = false;
-		}
+		else
+			free_fn(sgl, alloc_size);
 		sgl = next;
 	}
 

Re: [PATCH] lib/scatterlist: fix memory leak with scsi-mq

[Christoph Hellwig]

On Thu, Oct 23, 2014 at 03:10:21PM -0400, Tony Battersby wrote:
> Fix a memory leak with scsi-mq triggered by commands with large data
> transfer length.

Thanks, this was indeed caused by a last minute change due to someone
complaining about my earlier version being a little too convoluted.

Thanks for tracking this down!

Re: [PATCH] lib/scatterlist: fix memory leak with scsi-mq

[Martin K. Petersen]

>>>>> "Tony" == Tony Battersby <tonyb@cybernetics.com> writes:

Tony> Fix a memory leak with scsi-mq triggered by commands with large
Tony> data transfer length.

Tony> Fixes: c53c6d6a68b1 ("scatterlist: allow chaining to preallocated
Tony> chunks") 

Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>

-- 
Martin K. Petersen	Oracle Linux Engineering