BUG: soft lockup in ip_set_udel

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3f8a27f9e27b Linux 4.19.211
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14c13c7cb00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9277b418617afe
dashboard link: https://syzkaller.appspot.com/bug?extid=2ab825ea1a50d28c1f55
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2ab825...@syzkaller.appspotmail.com

watchdog: BUG: soft lockup - CPU#1 stuck for 22s! [syz-executor.1:5076]
Modules linked in:
irq event stamp: 4923
hardirqs last enabled at (4922): [<ffffffff81003ce4>] trace_hardirqs_on_thunk+0x1a/0x1c
hardirqs last disabled at (4923): [<ffffffff81003d00>] trace_hardirqs_off_thunk+0x1a/0x1c
softirqs last enabled at (100): [<ffffffff86768005>] rcu_read_unlock_bh include/linux/rcupdate.h:717 [inline]
softirqs last enabled at (100): [<ffffffff86768005>] __dev_queue_xmit+0x15f5/0x2e00 net/core/dev.c:3865
softirqs last disabled at (102): [<ffffffff86ba6ac2>] spin_lock_bh include/linux/spinlock.h:334 [inline]
softirqs last disabled at (102): [<ffffffff86ba6ac2>] call_ad+0x132/0x540 net/netfilter/ipset/ip_set_core.c:1505
CPU: 1 PID: 5076 Comm: syz-executor.1 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:hash_ip4_del+0xd5/0xc70 net/netfilter/ipset/ip_set_hash_gen.h:837
Code: fa 45 84 e4 0f 84 7d 09 00 00 e8 26 18 a6 fa 48 89 da 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 0f 85 7d 0a 00 00 <48> 8b 03 48 8d 7b 5c 48 89 fa 48 c1 ea 03 48 89 44 24 28 48 b8 00
RSP: 0018:ffff88803a5af090 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: ffff8880aa23c900 RCX: ffffc90007ee3000
RDX: 1ffff11015447920 RSI: ffffffff86bc6d4a RDI: 0000000000000005
RBP: ffff88803a5af198 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000000 R12: 0000000000000001
R13: 00000000e0000002 R14: 000000001c1ff30d R15: ffff88803a5af198
FS: 00007f5952752700(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000040 CR3: 000000009226d000 CR4: 00000000003426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
hash_ip4_uadt+0x520/0x780 net/netfilter/ipset/ip_set_hash_ip.c:155
call_ad+0x178/0x540 net/netfilter/ipset/ip_set_core.c:1506
ip_set_udel+0x519/0xa90 net/netfilter/ipset/ip_set_core.c:1642
nfnetlink_rcv_msg+0xc4f/0xf60 net/netfilter/nfnetlink.c:233
netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2463
nfnetlink_rcv+0x1b2/0x420 net/netfilter/nfnetlink.c:565
netlink_unicast_kernel net/netlink/af_netlink.c:1325 [inline]
netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1351
netlink_sendmsg+0x6c3/0xc50 net/netlink/af_netlink.c:1917
sock_sendmsg_nosec net/socket.c:651 [inline]
sock_sendmsg+0xc3/0x120 net/socket.c:661
___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2227
__sys_sendmsg net/socket.c:2265 [inline]
__do_sys_sendmsg net/socket.c:2274 [inline]
__se_sys_sendmsg net/socket.c:2272 [inline]
__x64_sys_sendmsg+0x132/0x220 net/socket.c:2272
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f59551dcae9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5952752188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f59552eff60 RCX: 00007f59551dcae9
RDX: 0000000000000000 RSI: 0000000020001080 RDI: 0000000000000003
RBP: 00007f5955236f25 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc9d77545f R14: 00007f5952752300 R15: 0000000000022000
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60
----------------
Code disassembly (best guess):
0: fa cli
1: 45 84 e4 test %r12b,%r12b
4: 0f 84 7d 09 00 00 je 0x987
a: e8 26 18 a6 fa callq 0xfaa61835
f: 48 89 da mov %rbx,%rdx
12: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
19: fc ff df
1c: 48 c1 ea 03 shr $0x3,%rdx
20: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1)
24: 0f 85 7d 0a 00 00 jne 0xaa7
* 2a: 48 8b 03 mov (%rbx),%rax <-- trapping instruction
2d: 48 8d 7b 5c lea 0x5c(%rbx),%rdi
31: 48 89 fa mov %rdi,%rdx
34: 48 c1 ea 03 shr $0x3,%rdx
38: 48 89 44 24 28 mov %rax,0x28(%rsp)
3d: 48 rex.W
3e: b8 .byte 0xb8


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.