[PATCH 5.4 150/168] RDMA/core: Fix protection fault in ib_mr_pool_destroy

Greg Kroah-Hartman
2020-03-10T12:55:25Z

From: Maor Gottlieb <maorg@mellanox.com>

commit e38b55ea0443da35a50a3eb2079ad3612cf763b9 upstream.

Fix NULL pointer dereference in the error flow of ib_create_qp_user
when accessing to uninitialized list pointers - rdma_mrs and sig_mrs.
The following crash from syzkaller revealed it.

kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN PTI
CPU: 1 PID: 23167 Comm: syz-executor.1 Not tainted 5.5.0-rc5 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
RIP: 0010:ib_mr_pool_destroy+0x81/0x1f0
Code: 00 00 fc ff df 49 c1 ec 03 4d 01 fc e8 a8 ea 72 fe 41 80 3c 24 00
0f 85 62 01 00 00 48 8b 13 48 89 d6 4c 8d 6a c8 48 c1 ee 03 <42> 80 3c
3e 00 0f 85 34 01 00 00 48 8d 7a 08 4c 8b 02 48 89 fe 48
RSP: 0018:ffffc9000951f8b0 EFLAGS: 00010046
RAX: 0000000000040000 RBX: ffff88810f268038 RCX: ffffffff82c41628
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc9000951f850
RBP: ffff88810f268020 R08: 0000000000000004 R09: fffff520012a3f0a
R10: 0000000000000001 R11: fffff520012a3f0a R12: ffffed1021e4d007
R13: ffffffffffffffc8 R14: 0000000000000246 R15: dffffc0000000000
FS: 00007f54bc788700(0000) GS:ffff88811b100000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000116920002 CR4: 0000000000360ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rdma_rw_cleanup_mrs+0x15/0x30
ib_destroy_qp_user+0x674/0x7d0
ib_create_qp_user+0xb01/0x11c0
create_qp+0x1517/0x2130
ib_uverbs_create_qp+0x13e/0x190
ib_uverbs_write+0xaa5/0xdf0
__vfs_write+0x7c/0x100
vfs_write+0x168/0x4a0
ksys_write+0xc8/0x200
do_syscall_64+0x9c/0x390
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x465b49
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 48 89 f8 48 89
f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01
f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f54bc787c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000465b49
RDX: 0000000000000040 RSI: 0000000020000540 RDI: 0000000000000003
RBP: 00007f54bc787c70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f54bc7886bc
R13: 00000000004ca2ec R14: 000000000070ded0 R15: 0000000000000005

Fixes: a060b5629ab0 ("IB/core: generic RDMA READ/WRITE API")
Link: https://lore.kernel.org/r/20200227112708.93023-1-leon@kernel.org
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/infiniband/core/core_priv.h | 15 +++++++++++++++
drivers/infiniband/core/uverbs_cmd.c | 10 ----------
drivers/infiniband/core/verbs.c | 10 ----------
3 files changed, 15 insertions(+), 20 deletions(-)

--- a/drivers/infiniband/core/core_priv.h
+++ b/drivers/infiniband/core/core_priv.h
@@ -338,6 +338,21 @@ static inline struct ib_qp *_ib_create_q
qp->pd = pd;
qp->uobject = uobj;
qp->real_qp = qp;
+
+ qp->qp_type = attr->qp_type;
+ qp->qp_context = attr->qp_context;
+ qp->rwq_ind_tbl = attr->rwq_ind_tbl;
+ qp->send_cq = attr->send_cq;
+ qp->recv_cq = attr->recv_cq;
+ qp->srq = attr->srq;
+ qp->rwq_ind_tbl = attr->rwq_ind_tbl;
+ qp->event_handler = attr->event_handler;
+
+ atomic_set(&qp->usecnt, 0);
+ spin_lock_init(&qp->mr_lock);
+ INIT_LIST_HEAD(&qp->rdma_mrs);
+ INIT_LIST_HEAD(&qp->sig_mrs);
+
/*
* We don't track XRC QPs for now, because they don't have PD
* and more importantly they are created internaly by driver,
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -1431,17 +1431,7 @@ static int create_qp(struct uverbs_attr_
if (ret)
goto err_cb;

- qp->pd = pd;
- qp->send_cq = attr.send_cq;
- qp->recv_cq = attr.recv_cq;
- qp->srq = attr.srq;
- qp->rwq_ind_tbl = ind_tbl;
- qp->event_handler = attr.event_handler;
- qp->qp_context = attr.qp_context;
- qp->qp_type = attr.qp_type;
- atomic_set(&qp->usecnt, 0);
atomic_inc(&pd->usecnt);
- qp->port = 0;
if (attr.send_cq)
atomic_inc(&attr.send_cq->usecnt);
if (attr.recv_cq)
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -1180,16 +1180,6 @@ struct ib_qp *ib_create_qp_user(struct i
if (ret)
goto err;

- qp->qp_type = qp_init_attr->qp_type;
- qp->rwq_ind_tbl = qp_init_attr->rwq_ind_tbl;
-
- atomic_set(&qp->usecnt, 0);
- qp->mrs_used = 0;
- spin_lock_init(&qp->mr_lock);
- INIT_LIST_HEAD(&qp->rdma_mrs);
- INIT_LIST_HEAD(&qp->sig_mrs);
- qp->port = 0;
-
if (qp_init_attr->qp_type == IB_QPT_XRC_TGT) {
struct ib_qp *xrc_qp =
create_xrc_qp_user(qp, qp_init_attr, udata);