[PATCH AUTOSEL for 4.14 086/100] RDMA/netlink: Fix general protection fault

[Sasha Levin <Alexander.Levin@microsoft.com>]

From: Leon Romanovsky <leonro@mellanox.com>

[ Upstream commit d0e312fe3d34c1bc014a7f8ec6540d05e8077483 ]

The RDMA netlink core code checks validity of messages by ensuring
that type and operand are in range. It works well for almost all
clients except NLDEV, which has cb_table less than number of operands.

Request to access such operand will trigger the following kernel panic.

This patch updates all places where cb_table is declared for the
consistency, but only NLDEV is actually need it.

general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN
Modules linked in:
CPU: 0 PID: 522 Comm: syz-executor6 Not tainted 4.13.0+ #4
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
task: ffff8800657799c0 task.stack: ffff8800695d000
RIP: 0010:rdma_nl_rcv_msg+0x13a/0x4c0
RSP: 0018:ffff8800695d7838 EFLAGS: 00010207
RAX: dffffc0000000000 RBX: 1ffff1000d2baf0b RCX: 00000000704ff4d7
RDX: 0000000000000000 RSI: ffffffff81ddb03c RDI: 00000003827fa6bc
RBP: ffff8800695d7900 R08: ffffffff82ec0578 R09: 0000000000000000
R10: ffff8800695d7900 R11: 0000000000000001 R12: 000000000000001c
R13: ffff880069d31e00 R14: 00000000ffffffff R15: ffff880069d357c0
FS:  00007fee6acb8700(0000) GS:ffff88006ca00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000201a9000 CR3: 0000000059766000 CR4: 00000000000006b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 ? rdma_nl_multicast+0x80/0x80
 rdma_nl_rcv+0x36b/0x4d0
 ? ibnl_put_attr+0xc0/0xc0
 netlink_unicast+0x4bd/0x6d0
 ? netlink_sendskb+0x50/0x50
 ? drop_futex_key_refs.isra.4+0x68/0xb0
 netlink_sendmsg+0x9ab/0xbd0
 ? nlmsg_notify+0x140/0x140
 ? wake_up_q+0xa1/0xf0
 ? drop_futex_key_refs.isra.4+0x68/0xb0
 sock_sendmsg+0x88/0xd0
 sock_write_iter+0x228/0x3c0
 ? sock_sendmsg+0xd0/0xd0
 ? do_futex+0x3e5/0xb20
 ? iov_iter_init+0xaf/0x1d0
 __vfs_write+0x46e/0x640
 ? sched_clock_cpu+0x1b/0x190
 ? __vfs_read+0x620/0x620
 ? __fget+0x23a/0x390
 ? rw_verify_area+0xca/0x290
 vfs_write+0x192/0x490
 SyS_write+0xde/0x1c0
 ? SyS_read+0x1c0/0x1c0
 ? trace_hardirqs_on_thunk+0x1a/0x1c
 entry_SYSCALL_64_fastpath+0x18/0xad
RIP: 0033:0x7fee6a74a219
RSP: 002b:00007fee6acb7d58 EFLAGS: 00000212 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000638000 RCX: 00007fee6a74a219
RDX: 0000000000000078 RSI: 0000000020141000 RDI: 0000000000000006
RBP: 0000000000000046 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: ffff8800695d7f98
R13: 0000000020141000 R14: 0000000000000006 R15: 00000000ffffffff
Code: d6 48 b8 00 00 00 00 00 fc ff df 66 41 81 e4 ff 03 44 8d 72 ff 4a 8d 3c b5 c0 a6 7f 82 44 89 b5 4c ff ff ff 48 89 f9 48 c1 e9 03 <0f> b6 0c 01 48 89 f8 83 e0 07 83 c0 03 38 c8 7c 08 84 c9 0f 85
RIP: rdma_nl_rcv_msg+0x13a/0x4c0 RSP: ffff8800695d7838
---[ end trace ba085d123959c8ec ]---
Kernel panic - not syncing: Fatal exception

Cc: syzkaller <syzkaller@googlegroups.com>
Fixes: b4c598a67ea1 ("RDMA/netlink: Implement nldev device dumpit calback")
Reviewed-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
 drivers/infiniband/core/cma.c    | 2 +-
 drivers/infiniband/core/device.c | 2 +-
 drivers/infiniband/core/iwcm.c   | 2 +-
 drivers/infiniband/core/nldev.c  | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 09063f0d86d2..e457dface2d2 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -4462,7 +4462,7 @@ static int cma_get_id_stats(struct sk_buff *skb, struct netlink_callback *cb)
 	return skb->len;
 }
 
-static const struct rdma_nl_cbs cma_cb_table[] = {
+static const struct rdma_nl_cbs cma_cb_table[RDMA_NL_RDMA_CM_NUM_OPS] = {
 	[RDMA_NL_RDMA_CM_ID_STATS] = { .dump = cma_get_id_stats},
 };
 
diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
index 5e1be4949d5f..30914f3baa5f 100644
--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -1146,7 +1146,7 @@ struct net_device *ib_get_net_dev_by_params(struct ib_device *dev,
 }
 EXPORT_SYMBOL(ib_get_net_dev_by_params);
 
-static const struct rdma_nl_cbs ibnl_ls_cb_table[] = {
+static const struct rdma_nl_cbs ibnl_ls_cb_table[RDMA_NL_LS_NUM_OPS] = {
 	[RDMA_NL_LS_OP_RESOLVE] = {
 		.doit = ib_nl_handle_resolve_resp,
 		.flags = RDMA_NL_ADMIN_PERM,
diff --git a/drivers/infiniband/core/iwcm.c b/drivers/infiniband/core/iwcm.c
index fcf42f6bb82a..30d7277249b8 100644
--- a/drivers/infiniband/core/iwcm.c
+++ b/drivers/infiniband/core/iwcm.c
@@ -80,7 +80,7 @@ const char *__attribute_const__ iwcm_reject_msg(int reason)
 }
 EXPORT_SYMBOL(iwcm_reject_msg);
 
-static struct rdma_nl_cbs iwcm_nl_cb_table[] = {
+static struct rdma_nl_cbs iwcm_nl_cb_table[RDMA_NL_IWPM_NUM_OPS] = {
 	[RDMA_NL_IWPM_REG_PID] = {.dump = iwpm_register_pid_cb},
 	[RDMA_NL_IWPM_ADD_MAPPING] = {.dump = iwpm_add_mapping_cb},
 	[RDMA_NL_IWPM_QUERY_MAPPING] = {.dump = iwpm_add_and_query_mapping_cb},
diff --git a/drivers/infiniband/core/nldev.c b/drivers/infiniband/core/nldev.c
index 2fae850a3eff..9a05245a1acf 100644
--- a/drivers/infiniband/core/nldev.c
+++ b/drivers/infiniband/core/nldev.c
@@ -303,7 +303,7 @@ out:	cb->args[0] = idx;
 	return skb->len;
 }
 
-static const struct rdma_nl_cbs nldev_cb_table[] = {
+static const struct rdma_nl_cbs nldev_cb_table[RDMA_NLDEV_NUM_OPS] = {
 	[RDMA_NLDEV_CMD_GET] = {
 		.doit = nldev_get_doit,
 		.dump = nldev_get_dumpit,
-- 
2.11.0