[PATCH AUTOSEL 4.19 029/206] RDMA/i40iw: Fix potential use after free

[Sasha Levin]

From: Pan Bian <bianpan2016@xxxxxxx>

[ Upstream commit da046d5f895fca18d63b15ac8faebd5bf784e23a ]

Release variable dst after logging dst->error to avoid possible use after
free.

Link: https://lore.kernel.org/r/1573022651-37171-1-git-send-email-bianpan2016@xxxxxxx
Signed-off-by: Pan Bian <bianpan2016@xxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/infiniband/hw/i40iw/i40iw_cm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/infiniband/hw/i40iw/i40iw_cm.c b/drivers/infiniband/hw/i40iw/i40iw_cm.c
index 4321b9e3dbb4b..0273d0404e740 100644
--- a/drivers/infiniband/hw/i40iw/i40iw_cm.c
+++ b/drivers/infiniband/hw/i40iw/i40iw_cm.c
@@ -2071,9 +2071,9 @@ static int i40iw_addr_resolve_neigh_ipv6(struct i40iw_device *iwdev,
 	dst = i40iw_get_dst_ipv6(&src_addr, &dst_addr);
 	if (!dst || dst->error) {
 		if (dst) {
-			dst_release(dst);
 			i40iw_pr_err("ip6_route_output returned dst->error = %d\n",
 				     dst->error);
+			dst_release(dst);
 		}
 		return rc;
 	}
-- 
2.25.1