syzbot


general protection fault in mld_clear_delrec

Status: upstream: reported on 2025/05/08 01:23
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+888c7330963d4b45da35@syzkaller.appspotmail.com
First crash: 4d13h, last: 1d21h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [net?] general protection fault in mld_clear_delrec 0 (1) 2025/05/08 01:23

Sample crash report:
veth1_vlan: left promiscuous mode
veth0_vlan: left promiscuous mode
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed
Oops: general protection fault, probably for non-canonical address 0xdffffc001ffee000: 0000 [#1] SMP KASAN NOPTI
KASAN: probably user-memory-access in range [0x00000000fff70000-0x00000000fff70007]
CPU: 0 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted 6.15.0-rc5-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Workqueue: netns cleanup_net
RIP: 0010:mld_clear_delrec+0x2a6/0x640 net/ipv6/mcast.c:838
Code: 20 00 0f 85 91 03 00 00 49 8b 5d 28 49 c7 45 28 00 00 00 00 48 85 db 75 37 e9 d4 00 00 00 e8 21 86 96 f7 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 0f 85 39 03 00 00 48 8b 2b 48 8d 7b 30 48 89 de e8
RSP: 0018:ffffc900001275f8 EFLAGS: 00010206
RAX: 000000001ffee000 RBX: 00000000fff70000 RCX: ffffffff8a24ad36
RDX: ffff88801ca80000 RSI: ffffffff8a24accf RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888033bf3c00 R14: ffff88805babf000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881249df000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f87f8f59348 CR3: 000000000e180000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ipv6_mc_destroy_dev+0x49/0x690 net/ipv6/mcast.c:2842
 addrconf_ifdown.isra.0+0x13ef/0x1a90 net/ipv6/addrconf.c:3997
 addrconf_notify+0x220/0x19e0 net/ipv6/addrconf.c:3777
 notifier_call_chain+0xb9/0x410 kernel/notifier.c:85
 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:2176
 call_netdevice_notifiers_extack net/core/dev.c:2214 [inline]
 call_netdevice_notifiers net/core/dev.c:2228 [inline]
 unregister_netdevice_many_notify+0xf9a/0x26f0 net/core/dev.c:11982
 unregister_netdevice_many net/core/dev.c:12046 [inline]
 default_device_exit_batch+0x853/0xaf0 net/core/dev.c:12538
 ops_exit_list+0x128/0x180 net/core/net_namespace.c:177
 cleanup_net+0x5c1/0xb30 net/core/net_namespace.c:654
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:mld_clear_delrec+0x2a6/0x640 net/ipv6/mcast.c:838
Code: 20 00 0f 85 91 03 00 00 49 8b 5d 28 49 c7 45 28 00 00 00 00 48 85 db 75 37 e9 d4 00 00 00 e8 21 86 96 f7 48 89 d8 48 c1 e8 03 <42> 80 3c 20 00 0f 85 39 03 00 00 48 8b 2b 48 8d 7b 30 48 89 de e8
RSP: 0018:ffffc900001275f8 EFLAGS: 00010206
RAX: 000000001ffee000 RBX: 00000000fff70000 RCX: ffffffff8a24ad36
RDX: ffff88801ca80000 RSI: ffffffff8a24accf RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888033bf3c00 R14: ffff88805babf000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff888124adf000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe3317d4800 CR3: 000000000e180000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	20 00                	and    %al,(%rax)
   2:	0f 85 91 03 00 00    	jne    0x399
   8:	49 8b 5d 28          	mov    0x28(%r13),%rbx
   c:	49 c7 45 28 00 00 00 	movq   $0x0,0x28(%r13)
  13:	00
  14:	48 85 db             	test   %rbx,%rbx
  17:	75 37                	jne    0x50
  19:	e9 d4 00 00 00       	jmp    0xf2
  1e:	e8 21 86 96 f7       	call   0xf7968644
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 20 00       	cmpb   $0x0,(%rax,%r12,1) <-- trapping instruction
  2f:	0f 85 39 03 00 00    	jne    0x36e
  35:	48 8b 2b             	mov    (%rbx),%rbp
  38:	48 8d 7b 30          	lea    0x30(%rbx),%rdi
  3c:	48 89 de             	mov    %rbx,%rsi
  3f:	e8                   	.byte 0xe8

Crashes (11):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/05 06:17 upstream 92a09c47464d b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in mld_clear_delrec
2025/05/04 01:13 upstream 2a239ffbebb5 b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root general protection fault in mld_clear_delrec
2025/05/06 16:56 net e8716b5b0dff ae98e6b9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in mld_clear_delrec
2025/05/06 06:14 net 4397684a292a ae98e6b9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in mld_clear_delrec
2025/05/06 05:48 net 4397684a292a ae98e6b9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in mld_clear_delrec
2025/05/05 23:03 net ebd297a2affa 6ca47dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in mld_clear_delrec
2025/05/05 18:58 net ebd297a2affa 6ca47dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in mld_clear_delrec
2025/05/05 18:45 net ebd297a2affa 6ca47dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in mld_clear_delrec
2025/05/05 04:13 net ebd297a2affa b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in mld_clear_delrec
2025/05/04 09:57 net ebd297a2affa b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in mld_clear_delrec
2025/05/05 15:26 net-next 836b313a14a3 6ca47dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce general protection fault in mld_clear_delrec
* Struck through repros no longer work on HEAD.