Patch "IB/core: Avoid crash on pkey enforcement failed in received MADs" has been added to the 4.14-stable tree

This is a note to let you know that I've just added the patch titled

IB/core: Avoid crash on pkey enforcement failed in received MADs

to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
ib-core-avoid-crash-on-pkey-enforcement-failed-in-received-mads.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Parav Pandit <[email protected]>
Date: Tue, 31 Oct 2017 10:33:18 -0500
Subject: IB/core: Avoid crash on pkey enforcement failed in received MADs

From: Parav Pandit <[email protected]>

commit 89548bcafec7ecfeea58c553f0834b5d575a66eb upstream.

Below kernel crash is observed when Pkey security enforcement fails on received MADs. This issue is reported in [1].

ib_free_recv_mad() accesses the rmpp_list, whose initialization is needed before accessing it.
When security enformcent fails on received MADs, MAD processing avoided due to security checks failed.

OpenSM[3770]: SM port is down
kernel: BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
kernel: IP: ib_free_recv_mad+0x44/0xa0 [ib_core]
kernel: PGD 0
kernel: P4D 0
kernel:

kernel: Oops: 0002 [#1] SMP
kernel: CPU: 0 PID: 2833 Comm: kworker/0:1H Tainted: P          IO    4.13.4-1-pve #1
kernel: Hardware name: Dell       XS23-TY3        /9CMP63, BIOS 1.71 09/17/2013
kernel: Workqueue: ib-comp-wq ib_cq_poll_work [ib_core]
kernel: task: ffffa069c6541600 task.stack: ffffb9a729054000
kernel: RIP: 0010:ib_free_recv_mad+0x44/0xa0 [ib_core]
kernel: RSP: 0018:ffffb9a729057d38 EFLAGS: 00010286
kernel: RAX: ffffa069cb138a48 RBX: ffffa069cb138a10 RCX: 0000000000000000
kernel: RDX: ffffb9a729057d38 RSI: 0000000000000000 RDI: ffffa069cb138a20
kernel: RBP: ffffb9a729057d60 R08: ffffa072d2d49800 R09: ffffa069cb138ae0
kernel: R10: ffffa069cb138ae0 R11: ffffa072b3994e00 R12: ffffb9a729057d38
kernel: R13: ffffa069d1c90000 R14: 0000000000000000 R15: ffffa069d1c90880
kernel: FS:  0000000000000000(0000) GS:ffffa069dba00000(0000) knlGS:0000000000000000
kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
kernel: CR2: 0000000000000008 CR3: 00000011f51f2000 CR4: 00000000000006f0
kernel: Call Trace:
kernel:  ib_mad_recv_done+0x5cc/0xb50 [ib_core]
kernel:  __ib_process_cq+0x5c/0xb0 [ib_core]
kernel:  ib_cq_poll_work+0x20/0x60 [ib_core]
kernel:  process_one_work+0x1e9/0x410
kernel:  worker_thread+0x4b/0x410
kernel:  kthread+0x109/0x140
kernel:  ? process_one_work+0x410/0x410
kernel:  ? kthread_create_on_node+0x70/0x70
kernel:  ? SyS_exit_group+0x14/0x20
kernel:  ret_from_fork+0x25/0x30
kernel: RIP: ib_free_recv_mad+0x44/0xa0 [ib_core] RSP: ffffb9a729057d38
kernel: CR2: 0000000000000008

[1] : https://www.spinics.net/lists/linux-rdma/msg56190.html

---
 drivers/infiniband/core/mad.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

@@ -1974,14 +1974,15 @@ static void ib_mad_complete_recv(struct
 	unsigned long flags;
 	int ret;
 
+	INIT_LIST_HEAD(&mad_recv_wc->rmpp_list);
 	ret = ib_mad_enforce_security(mad_agent_priv,
 				      mad_recv_wc->wc->pkey_index);
 	if (ret) {
 		ib_free_recv_mad(mad_recv_wc);
 		deref_mad_agent(mad_agent_priv);
+		return;
 	}
 
-	INIT_LIST_HEAD(&mad_recv_wc->rmpp_list);
 	list_add(&mad_recv_wc->recv_buf.list, &mad_recv_wc->rmpp_list);
 	if (ib_mad_kernel_rmpp_agent(&mad_agent_priv->agent)) {
 		mad_recv_wc = ib_process_rmpp_recv_wc(mad_agent_priv,

Patches currently in stable-queue which might be from [email protected] are

queue-4.14/ib-core-only-maintain-real-qps-in-the-security-lists.patch queue-4.14/ib-cm-fix-memory-corruption-in-handling-cm-request.patch queue-4.14/ib-core-avoid-crash-on-pkey-enforcement-failed-in-received-mads.patch