[PATCH 5.11 184/210] RDMA/qedr: Fix kernel panic when trying to access recv_cq

Greg Kroah-Hartman
2021-04-12T09:43:27Z

From: Kamal Heib <kamalheib1@gmail.com>

[ Upstream commit e1ad897b9c738d5550be6762bf3a6ef1672259a4 ]

As INI QP does not require a recv_cq, avoid the following null pointer
dereference by checking if the qp_type is not INI before trying to extract
the recv_cq.

BUG: kernel NULL pointer dereference, address: 00000000000000e0
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
CPU: 0 PID: 54250 Comm: mpitests-IMB-MP Not tainted 5.12.0-rc5 #1
Hardware name: Dell Inc. PowerEdge R320/0KM5PX, BIOS 2.7.0 08/19/2019
RIP: 0010:qedr_create_qp+0x378/0x820 [qedr]
Code: 02 00 00 50 e8 29 d4 a9 d1 48 83 c4 18 e9 65 fe ff ff 48 8b 53 10 48 8b 43 18 44 8b 82 e0 00 00 00 45 85 c0 0f 84 10 74 00 00 <8b> b8 e0 00 00 00 85 ff 0f 85 50 fd ff ff e9 fd 73 00 00 48 8d bd
RSP: 0018:ffff9c8f056f7a70 EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffff9c8f056f7b58 RCX: 0000000000000009
RDX: ffff8c41a9744c00 RSI: ffff9c8f056f7b58 RDI: ffff8c41c0dfa280
RBP: ffff8c41c0dfa280 R08: 0000000000000002 R09: 0000000000000001
R10: 0000000000000000 R11: ffff8c41e06fc608 R12: ffff8c4194052000
R13: 0000000000000000 R14: ffff8c4191546070 R15: ffff8c41c0dfa280
FS: 00007f78b2787b80(0000) GS:ffff8c43a3200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000000e0 CR3: 00000001011d6002 CR4: 00000000001706f0
Call Trace:
ib_uverbs_handler_UVERBS_METHOD_QP_CREATE+0x4e4/0xb90 [ib_uverbs]
? ib_uverbs_cq_event_handler+0x30/0x30 [ib_uverbs]
ib_uverbs_run_method+0x6f6/0x7a0 [ib_uverbs]
? ib_uverbs_handler_UVERBS_METHOD_QP_DESTROY+0x70/0x70 [ib_uverbs]
? __cond_resched+0x15/0x30
? __kmalloc+0x5a/0x440
ib_uverbs_cmd_verbs+0x195/0x360 [ib_uverbs]
? xa_load+0x6e/0x90
? cred_has_capability+0x7c/0x130
? avc_has_extended_perms+0x17f/0x440
? vma_link+0xae/0xb0
? vma_set_page_prot+0x2a/0x60
? mmap_region+0x298/0x6c0
? do_mmap+0x373/0x520
? selinux_file_ioctl+0x17f/0x220
ib_uverbs_ioctl+0xa7/0x110 [ib_uverbs]
__x64_sys_ioctl+0x84/0xc0
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f78b120262b

Fixes: 06e8d1df46ed ("RDMA/qedr: Add support for user mode XRC-SRQ's")
Link: https://lore.kernel.org/r/20210404125501.154789-1-kamalheib1@gmail.com
Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/infiniband/hw/qedr/verbs.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/infiniband/hw/qedr/verbs.c b/drivers/infiniband/hw/qedr/verbs.c
index 0eb6a7a618e0..9ea542270ed4 100644
--- a/drivers/infiniband/hw/qedr/verbs.c
+++ b/drivers/infiniband/hw/qedr/verbs.c
@@ -1244,7 +1244,8 @@ static int qedr_check_qp_attrs(struct ib_pd *ibpd, struct qedr_dev *dev,
* TGT QP isn't associated with RQ/SQ
*/
if ((attrs->qp_type != IB_QPT_GSI) && (dev->gsi_qp_created) &&
- (attrs->qp_type != IB_QPT_XRC_TGT)) {
+ (attrs->qp_type != IB_QPT_XRC_TGT) &&
+ (attrs->qp_type != IB_QPT_XRC_INI)) {
struct qedr_cq *send_cq = get_qedr_cq(attrs->send_cq);
struct qedr_cq *recv_cq = get_qedr_cq(attrs->recv_cq);

--
2.30.2