From: Eric Dumazet edumazet@google.com
[ Upstream commit cb3c0e6bdf64d0d124e94ce43cbe4ccbb9b37f51 ]
NLA_BINARY can be confusing, since .len value represents the max size of the blob.
cls_rsvp really wants user space to provide long enough data for TCA_RSVP_DST and TCA_RSVP_SRC attributes.
BUG: KMSAN: uninit-value in rsvp_get net/sched/cls_rsvp.h:258 [inline] BUG: KMSAN: uninit-value in gen_handle net/sched/cls_rsvp.h:402 [inline] BUG: KMSAN: uninit-value in rsvp_change+0x1ae9/0x4220 net/sched/cls_rsvp.h:572 CPU: 1 PID: 13228 Comm: syz-executor.1 Not tainted 5.5.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x220 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 rsvp_get net/sched/cls_rsvp.h:258 [inline] gen_handle net/sched/cls_rsvp.h:402 [inline] rsvp_change+0x1ae9/0x4220 net/sched/cls_rsvp.h:572 tc_new_tfilter+0x31fe/0x5010 net/sched/cls_api.c:2104 rtnetlink_rcv_msg+0xcb7/0x1570 net/core/rtnetlink.c:5415 netlink_rcv_skb+0x451/0x650 net/netlink/af_netlink.c:2477 rtnetlink_rcv+0x50/0x60 net/core/rtnetlink.c:5442 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0xf9e/0x1100 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x1248/0x14d0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:639 [inline] sock_sendmsg net/socket.c:659 [inline] ____sys_sendmsg+0x12b6/0x1350 net/socket.c:2330 ___sys_sendmsg net/socket.c:2384 [inline] __sys_sendmsg+0x451/0x5f0 net/socket.c:2417 __do_sys_sendmsg net/socket.c:2426 [inline] __se_sys_sendmsg+0x97/0xb0 net/socket.c:2424 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2424 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45b349 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f269d43dc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f269d43e6d4 RCX: 000000000045b349 RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000009c2 R14: 00000000004cb338 R15: 000000000075bfd4
Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline] kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:82 slab_alloc_node mm/slub.c:2774 [inline] __kmalloc_node_track_caller+0xb40/0x1200 mm/slub.c:4382 __kmalloc_reserve net/core/skbuff.c:141 [inline] __alloc_skb+0x2fd/0xac0 net/core/skbuff.c:209 alloc_skb include/linux/skbuff.h:1049 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1174 [inline] netlink_sendmsg+0x7d3/0x14d0 net/netlink/af_netlink.c:1892 sock_sendmsg_nosec net/socket.c:639 [inline] sock_sendmsg net/socket.c:659 [inline] ____sys_sendmsg+0x12b6/0x1350 net/socket.c:2330 ___sys_sendmsg net/socket.c:2384 [inline] __sys_sendmsg+0x451/0x5f0 net/socket.c:2417 __do_sys_sendmsg net/socket.c:2426 [inline] __se_sys_sendmsg+0x97/0xb0 net/socket.c:2424 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2424 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fixes: 6fa8c0144b77 ("[NET_SCHED]: Use nla_policy for attribute validation in classifiers") Signed-off-by: Eric Dumazet edumazet@google.com Reported-by: syzbot syzkaller@googlegroups.com Acked-by: Cong Wang xiyou.wangcong@gmail.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/sched/cls_rsvp.h | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)
--- a/net/sched/cls_rsvp.h +++ b/net/sched/cls_rsvp.h @@ -475,10 +475,8 @@ static u32 gen_tunnel(struct rsvp_head *
static const struct nla_policy rsvp_policy[TCA_RSVP_MAX + 1] = { [TCA_RSVP_CLASSID] = { .type = NLA_U32 }, - [TCA_RSVP_DST] = { .type = NLA_BINARY, - .len = RSVP_DST_LEN * sizeof(u32) }, - [TCA_RSVP_SRC] = { .type = NLA_BINARY, - .len = RSVP_DST_LEN * sizeof(u32) }, + [TCA_RSVP_DST] = { .len = RSVP_DST_LEN * sizeof(u32) }, + [TCA_RSVP_SRC] = { .len = RSVP_DST_LEN * sizeof(u32) }, [TCA_RSVP_PINFO] = { .len = sizeof(struct tc_rsvp_pinfo) }, };