syzbot


general protection fault in codel_change

Status: closed as invalid on 2025/06/11 14:04
Subsystems: net
[Documentation on labels]
First crash: 118d, last: 102d
Cause bisection: failed (error log, bisect log)
  
Last patch testing requests (2)
Created Duration User Patch Repo Result
2025/06/11 12:25 51m edumazet@google.com upstream OK log
2025/05/15 15:27 35m edumazet@google.com upstream report log

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f]
CPU: 0 UID: 0 PID: 5937 Comm: syz-executor614 Not tainted 6.15.0-rc5-syzkaller-00022-g01f95500a162 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
RIP: 0010:qdisc_pkt_len include/net/sch_generic.h:821 [inline]
RIP: 0010:codel_change+0x4cb/0x930 net/sched/sch_codel.c:149
Code: e8 fa 5c 54 f8 49 89 dc 43 80 7c 25 00 00 74 08 4c 89 ff e8 c7 2c b4 f8 49 c7 07 00 00 00 00 4d 8d 6f 28 4c 89 e8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 dc 00 00 00 45 8b 6d 00 48 8b 84 24 90
RSP: 0018:ffffc90004357200 EFLAGS: 00010206
RAX: 0000000000000005 RBX: ffff88806f5e90d8 RCX: ffff88802ecebc00
RDX: 0000000000000000 RSI: ffff888028e16000 RDI: ffff888028e16000
RBP: ffffc90004357370 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200086ae30 R12: dffffc0000000000
R13: 0000000000000028 R14: 000000000000007a R15: 0000000000000000
FS:  000055559154d480(0000) GS:ffff8881260fd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd80deee58 CR3: 000000007e398000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 qdisc_change net/sched/sch_api.c:1394 [inline]
 __tc_modify_qdisc net/sched/sch_api.c:1727 [inline]
 tc_modify_qdisc+0x1897/0x20b0 net/sched/sch_api.c:1821
 rtnetlink_rcv_msg+0x779/0xb70 net/core/rtnetlink.c:6964
 netlink_rcv_skb+0x219/0x490 net/netlink/af_netlink.c:2534
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x219/0x270 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+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb5048f7b19
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 01 1a 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffff2671a78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fb5048f7b19
RDX: 0000000004040840 RSI: 0000200000000280 RDI: 0000000000000007
RBP: 00007ffff2671ae0 R08: 00007ffff2671ae0 R09: 00000000000f4240
R10: 00007ffff2671a80 R11: 0000000000000246 R12: 00000000000f4240
R13: 00000000000181ac R14: 00007ffff2671aac R15: 00007ffff2671ac0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:qdisc_pkt_len include/net/sch_generic.h:821 [inline]
RIP: 0010:codel_change+0x4cb/0x930 net/sched/sch_codel.c:149
Code: e8 fa 5c 54 f8 49 89 dc 43 80 7c 25 00 00 74 08 4c 89 ff e8 c7 2c b4 f8 49 c7 07 00 00 00 00 4d 8d 6f 28 4c 89 e8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 dc 00 00 00 45 8b 6d 00 48 8b 84 24 90
RSP: 0018:ffffc90004357200 EFLAGS: 00010206
RAX: 0000000000000005 RBX: ffff88806f5e90d8 RCX: ffff88802ecebc00
RDX: 0000000000000000 RSI: ffff888028e16000 RDI: ffff888028e16000
RBP: ffffc90004357370 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200086ae30 R12: dffffc0000000000
R13: 0000000000000028 R14: 000000000000007a R15: 0000000000000000
FS:  000055559154d480(0000) GS:ffff8881260fd000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffd80deee58 CR3: 000000007e398000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	e8 fa 5c 54 f8       	call   0xf8545cff
   5:	49 89 dc             	mov    %rbx,%r12
   8:	43 80 7c 25 00 00    	cmpb   $0x0,0x0(%r13,%r12,1)
   e:	74 08                	je     0x18
  10:	4c 89 ff             	mov    %r15,%rdi
  13:	e8 c7 2c b4 f8       	call   0xf8b42cdf
  18:	49 c7 07 00 00 00 00 	movq   $0x0,(%r15)
  1f:	4d 8d 6f 28          	lea    0x28(%r15),%r13
  23:	4c 89 e8             	mov    %r13,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 0f b6 04 20       	movzbl (%rax,%r12,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	0f 85 dc 00 00 00    	jne    0x113
  37:	45 8b 6d 00          	mov    0x0(%r13),%r13d
  3b:	48                   	rex.W
  3c:	8b                   	.byte 0x8b
  3d:	84 24 90             	test   %ah,(%rax,%rdx,4)

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/06 12:22 upstream 01f95500a162 ae98e6b9 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root general protection fault in codel_change
2025/05/06 10:44 upstream 01f95500a162 ae98e6b9 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root general protection fault in codel_change
2025/05/03 19:14 upstream 95d3481af6dc b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in codel_change
2025/05/03 19:14 upstream 95d3481af6dc b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in codel_change
2025/04/29 13:28 upstream ca91b9500108 aeb6ec69 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in codel_change
2025/04/29 13:28 upstream ca91b9500108 aeb6ec69 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in codel_change
2025/04/29 13:27 upstream ca91b9500108 aeb6ec69 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in codel_change
* Struck through repros no longer work on HEAD.