syzbot


general protection fault in find_match

Status: premoderation: reported on 2025/04/08 10:01
Reported-by: syzbot+fdf88e02000ad656bb67@syzkaller.appspotmail.com
First crash: 69d, last: 46d
Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in find_match net C done error 10 1948d 2135d 0/28 closed as invalid on 2020/04/17 19:54
upstream general protection fault in find_match (3) net 2 980d 1022d 0/28 auto-obsoleted due to no activity on 2023/01/16 14:40
android-6-1 general protection fault in find_match 2 11d 35d 0/2 premoderation: reported on 2025/05/12 10:56
upstream general protection fault in find_match (4) net 1 664d 660d 0/28 auto-obsoleted due to no activity on 2023/11/20 22:29
upstream general protection fault in find_match (2) net 4 1572d 1637d 0/28 auto-closed as invalid on 2021/06/26 04:02
linux-5.15 BUG: unable to handle kernel paging request in find_match 5 24d 80d 0/3 upstream: reported on 2025/03/28 21:20
upstream general protection fault in find_match (5) net 2 371d 372d 26/28 fixed on 2024/07/10 10:07
linux-4.19 general protection fault in find_match C error 1 1365d 2063d 0/1 upstream: reported C repro on 2019/10/23 12:46
android-5-10 general protection fault in find_match 40 10d 73d 0/2 premoderation: reported on 2025/04/04 19:16
linux-6.1 BUG: unable to handle kernel paging request in find_match 12 9h31m 19d 0/3 upstream: reported on 2025/05/28 21:21

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc000000005e: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000002f0-0x00000000000002f7]
CPU: 0 PID: 32515 Comm: syz.0.13357 Tainted: G        W         5.15.180-syzkaller-00024-g88c4075c39ed #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:__in6_dev_get include/net/addrconf.h:341 [inline]
RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:432 [inline]
RIP: 0010:find_match+0xb7/0xf20 net/ipv6/route.c:741
Code: 7c 05 00 00 74 08 48 89 df e8 e5 d4 87 fd 48 89 d8 bb f0 02 00 00 48 03 18 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 bb d4 87 fd 48 8b 1b 48 85 db 0f 84
RSP: 0018:ffffc90000006fa0 EFLAGS: 00010202
RAX: 000000000000005e RBX: 00000000000002f0 RCX: dffffc0000000000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000007058 R08: ffffc90000007380 R09: ffffc90000007390
R10: fffff52000000e92 R11: 1ffff92000000e8e R12: 0000000000000201
R13: 1ffff110246200c4 R14: 0000000000000000 R15: 0000000000000003
FS:  0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d613ff8 CR3: 000000000660f000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000097 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rt6_nh_find_match+0xd9/0x140 net/ipv6/route.c:781
 nexthop_for_each_fib6_nh+0xf6/0x1e0 net/ipv4/nexthop.c:1242
 __find_rr_leaf+0x50f/0x900 net/ipv6/route.c:822
 find_rr_leaf net/ipv6/route.c:859 [inline]
 rt6_select net/ipv6/route.c:894 [inline]
 fib6_table_lookup+0x631/0x9f0 net/ipv6/route.c:2189
 ip6_pol_route+0x145/0x1110 net/ipv6/route.c:2225
 ip6_pol_route_output+0x51/0x80 net/ipv6/route.c:2601
 pol_lookup_func include/net/ip6_fib.h:592 [inline]
 fib6_rule_lookup+0x2ef/0x560 net/ipv6/fib6_rules.c:120
 ip6_route_output_flags_noref+0x283/0x340 net/ipv6/route.c:2633
 ip6_route_output_flags+0x3c/0x200 net/ipv6/route.c:2646
 ip6_dst_lookup_tail+0x591/0x1370 net/ipv6/ip6_output.c:1129
 ip6_dst_lookup_flow+0x49/0xc0 net/ipv6/ip6_output.c:1232
 tipc_udp_xmit+0x306/0x8d0 net/tipc/udp_media.c:210
 tipc_udp_send_msg+0x20c/0x2e0 net/tipc/udp_media.c:271
 tipc_bearer_xmit_skb+0x27d/0x360 net/tipc/bearer.c:564
 tipc_disc_timeout+0x6a2/0x830 net/tipc/discover.c:338
 call_timer_fn+0x38/0x290 kernel/time/timer.c:1457
 expire_timers kernel/time/timer.c:1502 [inline]
 __run_timers+0x639/0x9a0 kernel/time/timer.c:1773
 run_timer_softirq+0x6a/0xf0 kernel/time/timer.c:1786
 handle_softirqs+0x250/0x560 kernel/softirq.c:565
 __do_softirq kernel/softirq.c:603 [inline]
 invoke_softirq kernel/softirq.c:425 [inline]
 __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:652
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:664
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa9/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:_compound_head include/linux/page-flags.h:205 [inline]
RIP: 0010:PageAnon include/linux/page-flags.h:510 [inline]
RIP: 0010:zap_pte_range mm/memory.c:1439 [inline]
RIP: 0010:zap_pmd_range mm/memory.c:1574 [inline]
RIP: 0010:zap_pud_range mm/memory.c:1603 [inline]
RIP: 0010:zap_p4d_range mm/memory.c:1624 [inline]
RIP: 0010:unmap_page_range+0xd6f/0x1ce0 mm/memory.c:1645
Code: 07 00 00 49 8d 5f 08 49 89 dc 49 c1 ec 03 48 b8 00 00 00 00 00 fc ff df 41 80 3c 04 00 74 08 48 89 df e8 24 95 0a 00 4c 8b 2b <44> 89 ee 83 e6 01 31 ff e8 64 2b cc ff 41 f6 c5 01 0f 85 2e 07 00
RSP: 0018:ffffc9000126f560 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffffea0004345f08 RCX: ffff88810b9462c0
RDX: ffffc9000126f8c0 RSI: 0000000000000001 RDI: ffffc9000126f8b8
RBP: ffffc9000126f730 R08: dffffc0000000000 R09: ffffed1021728c59
R10: ffffed1021728c59 R11: 1ffff11021728c58 R12: 1ffffd4000868be1
R13: 0000000000000000 R14: ffff888138678e88 R15: ffffea0004345f00
 unmap_single_vma mm/memory.c:1690 [inline]
 unmap_vmas+0x258/0x360 mm/memory.c:1722
 exit_mmap+0x3e6/0x860 mm/mmap.c:3233
 __mmput+0x93/0x320 kernel/fork.c:1180
 mmput+0x50/0x150 kernel/fork.c:1203
 exit_mm kernel/exit.c:554 [inline]
 do_exit+0x9ca/0x27a0 kernel/exit.c:867
 do_group_exit+0x141/0x310 kernel/exit.c:1002
 get_signal+0x66a/0x1480 kernel/signal.c:2907
 arch_do_signal_or_restart+0xc1/0x10f0 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0xa7/0xe0 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f833660c969
Code: Unable to access opcode bytes at RIP 0x7f833660c93f.
RSP: 002b:00007f8334c750e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007f8336833fa8 RCX: 00007f833660c969
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f8336833fac
RBP: 00007f8336833fa0 R08: 003a7d81b21f7725 R09: 0000000000000000
R10: 0000000000000040 R11: 0000000000000246 R12: 00007f8336833fac
R13: 0000000000000000 R14: 00007ffd3520a300 R15: 00007ffd3520a3e8
 </TASK>
Modules linked in:
---[ end trace e82dcbc6bbdd91d7 ]---
RIP: 0010:__in6_dev_get include/net/addrconf.h:341 [inline]
RIP: 0010:ip6_ignore_linkdown include/net/addrconf.h:432 [inline]
RIP: 0010:find_match+0xb7/0xf20 net/ipv6/route.c:741
Code: 7c 05 00 00 74 08 48 89 df e8 e5 d4 87 fd 48 89 d8 bb f0 02 00 00 48 03 18 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 bb d4 87 fd 48 8b 1b 48 85 db 0f 84
RSP: 0018:ffffc90000006fa0 EFLAGS: 00010202
RAX: 000000000000005e RBX: 00000000000002f0 RCX: dffffc0000000000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000007058 R08: ffffc90000007380 R09: ffffc90000007390
R10: fffff52000000e92 R11: 1ffff92000000e8e R12: 0000000000000201
R13: 1ffff110246200c4 R14: 0000000000000000 R15: 0000000000000003
FS:  0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d613ff8 CR3: 000000000660f000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000097 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	7c 05                	jl     0x7
   2:	00 00                	add    %al,(%rax)
   4:	74 08                	je     0xe
   6:	48 89 df             	mov    %rbx,%rdi
   9:	e8 e5 d4 87 fd       	call   0xfd87d4f3
   e:	48 89 d8             	mov    %rbx,%rax
  11:	bb f0 02 00 00       	mov    $0x2f0,%ebx
  16:	48 03 18             	add    (%rax),%rbx
  19:	48 89 d8             	mov    %rbx,%rax
  1c:	48 c1 e8 03          	shr    $0x3,%rax
  20:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  27:	fc ff df
* 2a:	80 3c 08 00          	cmpb   $0x0,(%rax,%rcx,1) <-- trapping instruction
  2e:	74 08                	je     0x38
  30:	48 89 df             	mov    %rbx,%rdi
  33:	e8 bb d4 87 fd       	call   0xfd87d4f3
  38:	48 8b 1b             	mov    (%rbx),%rbx
  3b:	48 85 db             	test   %rbx,%rbx
  3e:	0f                   	.byte 0xf
  3f:	84                   	.byte 0x84

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/01 13:09 android13-5.15-lts 88c4075c39ed 51b137cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in find_match
2025/04/17 03:51 android13-5.15-lts 8034ec1338e8 a95239b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in find_match
2025/04/08 10:00 android13-5.15-lts 5e1b899f19c3 a775275d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 general protection fault in find_match
* Struck through repros no longer work on HEAD.