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general protection fault in ip_check_mc_rcu

Status: closed as invalid on 2025/07/31 09:32
Subsystems: net
[Documentation on labels]
First crash: 67d, last: 67d
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Read in ip_check_mc_rcu net 19 C inconclusive error 30 1446d 1673d 0/29 closed as invalid on 2022/11/15 19:19
linux-4.19 KASAN: use-after-free Read in ip_check_mc_rcu 19 syz done 7 1459d 1610d 1/1 fixed on 2021/09/26 12:12
android-54 KASAN: use-after-free Read in ip_check_mc_rcu 19 C 5 1426d 1634d 0/2 auto-obsoleted due to no activity on 2023/04/22 05:06
linux-4.14 KASAN: use-after-free Read in ip_check_mc_rcu 19 C error 4 1078d 1642d 0/1 upstream: reported C repro on 2021/02/22 02:16

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc001fffe03a: 0000 [#1] SMP KASAN PTI
KASAN: probably user-memory-access in range [0x00000000ffff01d0-0x00000000ffff01d7]
CPU: 0 UID: 0 PID: 9580 Comm: syz.5.983 Not tainted 6.16.0-rc1-syzkaller-00102-g5466491c9e33 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:ip_check_mc_rcu+0xa4/0x680 net/ipv4/igmp.c:2818
Code: d0 f7 eb 05 e8 7d 02 d0 f7 4d 85 ed 74 6b 41 69 c7 47 86 c8 61 c1 e8 17 4c 8d 34 c5 00 00 00 00 4d 01 ee 4c 89 f0 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 f7 e8 be 79 33 f8 4d 8b 36 e8 26 d3 75 01
RSP: 0018:ffffc9000abcf500 EFLAGS: 00010206
RAX: 000000001fffe03a RBX: dffffc0000000000 RCX: 0000000000080000
RDX: ffffc9001ba01000 RSI: 0000000000000364 RDI: 0000000000000365
RBP: 0000000000000084 R08: 0000000000000000 R09: ffffffff89ed4d92
R10: ffffc9000abcf620 R11: fffff52001579eca R12: 0000000000000001
R13: 00000000ffff0000 R14: 00000000ffff01d0 R15: 00000000020000e0
FS:  00007f7643fdc6c0(0000) GS:ffff888125c52000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000001000 CR3: 000000003b77a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __mkroute_output net/ipv4/route.c:2591 [inline]
 ip_route_output_key_hash_rcu+0xe65/0x23a0 net/ipv4/route.c:2864
 ip_route_output_key_hash+0x1b9/0x2e0 net/ipv4/route.c:2694
 __ip_route_output_key include/net/route.h:169 [inline]
 ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2921
 raw_sendmsg+0x1038/0x18b0 net/ipv4/raw.c:628
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x19c/0x270 net/socket.c:727
 ____sys_sendmsg+0x505/0x830 net/socket.c:2566
 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620
 __sys_sendmsg net/socket.c:2652 [inline]
 __do_sys_sendmsg net/socket.c:2657 [inline]
 __se_sys_sendmsg net/socket.c:2655 [inline]
 __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2655
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f764318e929
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7643fdc038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f76433b5fa0 RCX: 00007f764318e929
RDX: 0000000000000000 RSI: 0000200000001000 RDI: 0000000000000004
RBP: 00007f7643210b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f76433b5fa0 R15: 00007ffc343583e8
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ip_check_mc_rcu+0xa4/0x680 net/ipv4/igmp.c:2818
Code: d0 f7 eb 05 e8 7d 02 d0 f7 4d 85 ed 74 6b 41 69 c7 47 86 c8 61 c1 e8 17 4c 8d 34 c5 00 00 00 00 4d 01 ee 4c 89 f0 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 f7 e8 be 79 33 f8 4d 8b 36 e8 26 d3 75 01
RSP: 0018:ffffc9000abcf500 EFLAGS: 00010206
RAX: 000000001fffe03a RBX: dffffc0000000000 RCX: 0000000000080000
RDX: ffffc9001ba01000 RSI: 0000000000000364 RDI: 0000000000000365
RBP: 0000000000000084 R08: 0000000000000000 R09: ffffffff89ed4d92
R10: ffffc9000abcf620 R11: fffff52001579eca R12: 0000000000000001
R13: 00000000ffff0000 R14: 00000000ffff01d0 R15: 00000000020000e0
FS:  00007f7643fdc6c0(0000) GS:ffff888125c52000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ea49ea6950 CR3: 000000003b77a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	d0 f7                	shl    %bh
   2:	eb 05                	jmp    0x9
   4:	e8 7d 02 d0 f7       	call   0xf7d00286
   9:	4d 85 ed             	test   %r13,%r13
   c:	74 6b                	je     0x79
   e:	41 69 c7 47 86 c8 61 	imul   $0x61c88647,%r15d,%eax
  15:	c1 e8 17             	shr    $0x17,%eax
  18:	4c 8d 34 c5 00 00 00 	lea    0x0(,%rax,8),%r14
  1f:	00
  20:	4d 01 ee             	add    %r13,%r14
  23:	4c 89 f0             	mov    %r14,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	80 3c 18 00          	cmpb   $0x0,(%rax,%rbx,1) <-- trapping instruction
  2e:	74 08                	je     0x38
  30:	4c 89 f7             	mov    %r14,%rdi
  33:	e8 be 79 33 f8       	call   0xf83379f6
  38:	4d 8b 36             	mov    (%r14),%r14
  3b:	e8 26 d3 75 01       	call   0x175d366

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/16 01:04 net 5466491c9e33 5f4b362d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce general protection fault in ip_check_mc_rcu
* Struck through repros no longer work on HEAD.