syzbot


KMSAN: uninit-value in rsvp_change

Status: fixed on 2020/02/18 14:31
Subsystems: net
[Documentation on labels]
Fix commit: cb3c0e6bdf64 cls_rsvp: fix rsvp_policy
First crash: 1606d, last: 1605d

Sample crash report:
IPVS: ftp: loaded support on port[0] = 21
=====================================================
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+0x1b09/0x4420 net/sched/cls_rsvp.h:572
CPU: 0 PID: 10943 Comm: syz-executor919 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+0x1b09/0x4420 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: 0033:0x440d19
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 7b 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fffc7f4be98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004a24f0 RCX: 0000000000440d19
RDX: 0000000000000000 RSI: 00000000200001c0 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 0000000120080522 R09: 0000000120080522
R10: 0000000120080522 R11: 0000000000000246 R12: 0000000000402220
R13: 00000000004022b0 R14: 0000000000000000 R15: 0000000000000000

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
=====================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/01/29 04:08 https://github.com/google/kmsan.git master 686a4f77cb0c c8e81ce4 .config console log report syz C ci-upstream-kmsan-gce
2020/01/28 05:04 https://github.com/google/kmsan.git master 686a4f77cb0c 56cd6c9b .config console log report syz ci-upstream-kmsan-gce
2020/01/29 02:34 https://github.com/google/kmsan.git master 686a4f77cb0c c8e81ce4 .config console log report ci-upstream-kmsan-gce
2020/01/28 03:30 https://github.com/google/kmsan.git master 686a4f77cb0c 56cd6c9b .config console log report ci-upstream-kmsan-gce
* Struck through repros no longer work on HEAD.