From: Nikita Zhandarovich <n.zhandarovich@xxxxxxxxxx> [ Upstream commit 283861a4c52c1ea4df3dd1b6fc75a50796ce3524 ] If get_ep_from_tid() fails to lookup non-NULL value for ep, ep is dereferenced later regardless of whether it is empty. This patch adds a simple sanity check to fix the issue. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 944661dd97f4 ("RDMA/iw_cxgb4: atomically lookup ep and get a reference") Signed-off-by: Nikita Zhandarovich <n.zhandarovich@xxxxxxxxxx> Link: https://lore.kernel.org/r/20230202184850.29882-1-n.zhandarovich@xxxxxxxxxx Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/infiniband/hw/cxgb4/cm.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c index ea3ddf0d24114..ced615b5ea096 100644 --- a/drivers/infiniband/hw/cxgb4/cm.c +++ b/drivers/infiniband/hw/cxgb4/cm.c @@ -2676,6 +2676,9 @@ static int pass_establish(struct c4iw_dev *dev, struct sk_buff *skb) u16 tcp_opt = ntohs(req->tcp_opt); ep = get_ep_from_tid(dev, tid); + if (!ep) + return 0; + pr_debug("ep %p tid %u\n", ep, ep->hwtid); ep->snd_seq = be32_to_cpu(req->snd_isn); ep->rcv_seq = be32_to_cpu(req->rcv_isn); -- 2.39.2