syzbot


BUG: corrupted list in nft_obj_del

Status: fixed on 2020/02/18 14:31
Subsystems: netfilter
[Documentation on labels]
Reported-by: syzbot+6ca99af7e70e298bd09d@syzkaller.appspotmail.com
Fix commit: 335178d5429c netfilter: nf_tables: fix flowtable list del corruption
First crash: 1534d, last: 1532d
Cause bisection: introduced by (bisect log) :
commit 20651cefd25ffa77a15cab5853b175a6dc975ec2
Author: Florian Westphal <fw@strlen.de>
Date: Tue Jan 9 13:30:48 2018 +0000

  netfilter: x_tables: unbreak module auto loading

Crash: general protection fault in get_info (log)
Repro: C syz .config
  
Discussions (1)
Title Replies (including bot) Last reply
BUG: corrupted list in nft_obj_del 1 (3) 2020/01/16 14:53

Sample crash report:
list_del corruption, ffff8880a44fac00->prev is LIST_POISON2 (dead000000000122)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:48!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 10662 Comm: syz-executor790 Not tainted 5.5.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__list_del_entry_valid.cold+0x37/0x4f lib/list_debug.c:48
Code: be fd 0f 0b 4c 89 ea 4c 89 f6 48 c7 c7 20 66 71 88 e8 c0 e7 be fd 0f 0b 4c 89 e2 4c 89 f6 48 c7 c7 80 66 71 88 e8 ac e7 be fd <0f> 0b 4c 89 f6 48 c7 c7 40 67 71 88 e8 9b e7 be fd 0f 0b cc cc cc
RSP: 0018:ffffc90001f97338 EFLAGS: 00010286
RAX: 000000000000004e RBX: ffff8880a44fac00 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815e5396 RDI: fffff520003f2e59
RBP: ffffc90001f97350 R08: 000000000000004e R09: ffffed1015d06621
R10: ffffed1015d06620 R11: ffff8880ae833107 R12: dead000000000122
R13: ffff88809704e970 R14: ffff8880a44fac00 R15: ffff8880a44fac08
FS:  00000000023cb880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005633f9c5b140 CR3: 000000008e266000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __list_del_entry include/linux/list.h:131 [inline]
 list_del_rcu include/linux/rculist.h:148 [inline]
 nft_obj_del+0xcb/0x1f0 net/netfilter/nf_tables_api.c:6970
 nf_tables_commit+0x1339/0x3b30 net/netfilter/nf_tables_api.c:7171
 nfnetlink_rcv_batch+0xc78/0x17a0 net/netfilter/nfnetlink.c:485
 nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:543 [inline]
 nfnetlink_rcv+0x3e7/0x460 net/netfilter/nfnetlink.c:561
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x58c/0x7d0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg+0xd7/0x130 net/socket.c:659
 ____sys_sendmsg+0x753/0x880 net/socket.c:2330
 ___sys_sendmsg+0x100/0x170 net/socket.c:2384
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2417
 __do_sys_sendmsg net/socket.c:2426 [inline]
 __se_sys_sendmsg net/socket.c:2424 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2424
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4406a9
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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffc91c96b78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004406a9
RDX: 0000000000042000 RSI: 0000000020000140 RDI: 0000000000000004
RBP: 00000000006ca018 R08: 0000000000000001 R09: 00000000004002c8
R10: 0000000000000009 R11: 0000000000000246 R12: 0000000000401f30
R13: 0000000000401fc0 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace 2ddc8e072ef81988 ]---
RIP: 0010:__list_del_entry_valid.cold+0x37/0x4f lib/list_debug.c:48
Code: be fd 0f 0b 4c 89 ea 4c 89 f6 48 c7 c7 20 66 71 88 e8 c0 e7 be fd 0f 0b 4c 89 e2 4c 89 f6 48 c7 c7 80 66 71 88 e8 ac e7 be fd <0f> 0b 4c 89 f6 48 c7 c7 40 67 71 88 e8 9b e7 be fd 0f 0b cc cc cc
RSP: 0018:ffffc90001f97338 EFLAGS: 00010286
RAX: 000000000000004e RBX: ffff8880a44fac00 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815e5396 RDI: fffff520003f2e59
RBP: ffffc90001f97350 R08: 000000000000004e R09: ffffed1015d06621
R10: ffffed1015d06620 R11: ffff8880ae833107 R12: dead000000000122
R13: ffff88809704e970 R14: ffff8880a44fac00 R15: ffff8880a44fac08
FS:  00000000023cb880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005633f9c5b140 CR3: 000000008e266000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/01/16 05:03 upstream 51d69817519f f9b69507 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2020/01/16 03:12 upstream 51d69817519f f9b69507 .config console log report syz C ci-upstream-kasan-gce-root
2020/01/16 01:24 upstream 51d69817519f f9b69507 .config console log report syz C ci-upstream-kasan-gce
2020/01/16 05:08 upstream 51d69817519f f9b69507 .config console log report syz C ci-upstream-kasan-gce-386
2020/01/16 00:09 net-old 8b792f84c637 f9b69507 .config console log report syz C ci-upstream-net-this-kasan-gce
2020/01/16 01:17 net-next-old 4e2fa6b90275 f9b69507 .config console log report syz C ci-upstream-net-kasan-gce
2020/01/18 05:20 linux-next 2747d5fdab78 3de7aabb .config console log report syz C ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.