[PATCH 4.4 024/132] RDMA/cm: Fix an attempt to use non-valid pointer when cleaning timewait

Greg Kroah-Hartman
2020-12-28T12:53:23Z

From: Leon Romanovsky <leonro@nvidia.com>

[ Upstream commit 340b940ea0ed12d9adbb8f72dea17d516b2019e8 ]

If cm_create_timewait_info() fails, the timewait_info pointer will contain
an error value and will be used in cm_remove_remote() later.

general protection fault, probably for non-canonical address 0xdffffc0000000024: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0×0000000000000120-0×0000000000000127]
CPU: 2 PID: 12446 Comm: syz-executor.3 Not tainted 5.10.0-rc5-5d4c0742a60e #27
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:cm_remove_remote.isra.0+0x24/0×170 drivers/infiniband/core/cm.c:978
Code: 84 00 00 00 00 00 41 54 55 53 48 89 fb 48 8d ab 2d 01 00 00 e8 7d bf 4b fe 48 89 ea 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <0f> b6 04 02 48 89 ea 83 e2 07 38 d0 7f 08 84 c0 0f 85 fc 00 00 00
RSP: 0018:ffff888013127918 EFLAGS: 00010006
RAX: dffffc0000000000 RBX: fffffffffffffff4 RCX: ffffc9000a18b000
RDX: 0000000000000024 RSI: ffffffff82edc573 RDI: fffffffffffffff4
RBP: 0000000000000121 R08: 0000000000000001 R09: ffffed1002624f1d
R10: 0000000000000003 R11: ffffed1002624f1c R12: ffff888107760c70
R13: ffff888107760c40 R14: fffffffffffffff4 R15: ffff888107760c9c
FS: 00007fe1ffcc1700(0000) GS:ffff88811a600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2ff21000 CR3: 000000010f504001 CR4: 0000000000370ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
cm_destroy_id+0x189/0×15b0 drivers/infiniband/core/cm.c:1155
cma_connect_ib drivers/infiniband/core/cma.c:4029 [inline]
rdma_connect_locked+0x1100/0×17c0 drivers/infiniband/core/cma.c:4107
rdma_connect+0x2a/0×40 drivers/infiniband/core/cma.c:4140
ucma_connect+0x277/0×340 drivers/infiniband/core/ucma.c:1069
ucma_write+0x236/0×2f0 drivers/infiniband/core/ucma.c:1724
vfs_write+0x220/0×830 fs/read_write.c:603
ksys_write+0x1df/0×240 fs/read_write.c:658
do_syscall_64+0x33/0×40 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: a977049dacde ("[PATCH] IB: Add the kernel CM implementation")
Link: https://lore.kernel.org/r/20201204064205.145795-1-leon@kernel.org
Reviewed-by: Maor Gottlieb <maorg@nvidia.com>
Reported-by: Amit Matityahu <mitm@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/infiniband/core/cm.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/infiniband/core/cm.c b/drivers/infiniband/core/cm.c
index 53c622c99ee40..ba713bc27c5f9 100644
--- a/drivers/infiniband/core/cm.c
+++ b/drivers/infiniband/core/cm.c
@@ -1252,6 +1252,7 @@ int ib_send_cm_req(struct ib_cm_id *cm_id,
id.local_id);
if (IS_ERR(cm_id_priv->timewait_info)) {
ret = PTR_ERR(cm_id_priv->timewait_info);
+ cm_id_priv->timewait_info = NULL;
goto out;
}

@@ -1681,6 +1682,7 @@ static int cm_req_handler(struct cm_work *work)
id.local_id);
if (IS_ERR(cm_id_priv->timewait_info)) {
ret = PTR_ERR(cm_id_priv->timewait_info);
+ cm_id_priv->timewait_info = NULL;
goto destroy;
}
cm_id_priv->timewait_info->work.remote_id = req_msg->local_comm_id;
--
2.27.0