RDMA/cxgb4: Fix potential null-ptr-deref in pass_establish()
Commit Message
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@fintech.ru>
---
drivers/infiniband/hw/cxgb4/cm.c | 4 ++++
1 file changed, 4 insertions(+)
Comments
On Thu, Feb 02, 2023 at 06:52:22AM -0800, Nikita Zhandarovich wrote:
> 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@fintech.ru>
> ---
> drivers/infiniband/hw/cxgb4/cm.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c
> index c16017f6e8db..f4a02c2ec02f 100644
> --- a/drivers/infiniband/hw/cxgb4/cm.c
> +++ b/drivers/infiniband/hw/cxgb4/cm.c
> @@ -2683,6 +2683,10 @@ 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) {
> + pr_warn("%s tid %d lookup failure!\n", __func__, tid);
> + return 0;
> + }
don't print please
Jason
@@ -2683,6 +2683,10 @@ 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) {
+ pr_warn("%s tid %d lookup failure!\n", __func__, tid);
+ 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);