Re: [PATCH][next] xsk: Fix null check on error return path

[Björn Töpel]

On 2020-09-02 17:07, Gustavo A. R. Silva wrote:

Currently, dma_map is being checked, when the right object identifier
to be null-checked is dma_map->dma_pages, instead.

Fix this by null-checking dma_map->dma_pages.

Addresses-Coverity-ID: 1496811 ("Logically dead code")
Fixes: 921b68692abb ("xsk: Enable sharing of dma mappings")
Signed-off-by: Gustavo A. R. Silva <gustavo...@kernel.org>

Nice catch!

Acked-by: Björn Töpel <bjorn.to...@intel.com>

---
  net/xdp/xsk_buff_pool.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/xdp/xsk_buff_pool.c b/net/xdp/xsk_buff_pool.c
index 795d7c81c0ca..5b00bc5707f2 100644
--- a/net/xdp/xsk_buff_pool.c
+++ b/net/xdp/xsk_buff_pool.c
@@ -287,7 +287,7 @@ static struct xsk_dma_map *xp_create_dma_map(struct device 
*dev, struct net_devi
                return NULL;

dma_map->dma_pages = kvcalloc(nr_pages, sizeof(*dma_map->dma_pages), GFP_KERNEL);

-       if (!dma_map) {
+       if (!dma_map->dma_pages) {
                kfree(dma_map);
                return NULL;
        }