Subject: [syzbot] [net?] [bpf?] general protection fault in __dev_flush

From: syzbot <[email-masked]>
Date: Thu, 18 Jul 2024 20:59:25 -0700

Hello,

syzbot found the following issue on:

HEAD commit:    68b59730459e Merge tag 'perf-tools-for-v6.11-2024-07-16' o..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14cb0ab5980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b6230d83d52af231
dashboard link: https://syzkaller.appspot.com/bug?extid=44623300f057a28baf1e
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8229997a3dbb/disk-68b59730.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fd51823e0836/vmlinux-68b59730.xz
kernel image: https://storage.googleapis.com/syzbot-assets/01811b27f987/bzImage-68b59730.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]

Oops: general protection fault, probably for non-canonical address 0xfbd5a5d5a0000001: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdead4ead00000008-0xdead4ead0000000f]
CPU: 1 PID: 8860 Comm: syz.0.1070 Not tainted 6.10.0-syzkaller-08280-g68b59730459e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:__list_del include/linux/list.h:195 [inline]
RIP: 0010:__list_del_clearprev include/linux/list.h:209 [inline]
RIP: 0010:__dev_flush+0xe4/0x160 kernel/bpf/devmap.c:428
Code: b8 00 00 00 00 00 fc ff df 41 80 7c 05 00 00 49 89 c5 74 08 48 89 df e8 6a c3 3d 00 48 8b 2b 48 8d 5d 08 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 3d c4 3d 00 4c 89 23 4c 89 e0 48
RSP: 0018:ffffc90000a18af0 EFLAGS: 00010212
RAX: 1bd5a9d5a0000001 RBX: dead4ead00000008 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffff8880b943e868
RBP: dead4ead00000000 R08: ffff8880b943e867 R09: ffff8880b943e858
R10: dffffc0000000000 R11: ffffed1017287d0d R12: 00000000ffffffff
R13: dffffc0000000000 R14: ffff8880b943e848 R15: 1ffff11017287d09
FS:  00007f33633c96c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffec0000 CR3: 0000000054f40000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 xdp_do_check_flushed+0x129/0x240 net/core/filter.c:4300
 __napi_poll+0xe4/0x490 net/core/dev.c:6774
 napi_poll net/core/dev.c:6840 [inline]
 net_rx_action+0x89b/0x1240 net/core/dev.c:6962
 handle_softirqs+0x2c6/0x970 kernel/softirq.c:554
 __do_softirq kernel/softirq.c:588 [inline]
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649
 common_interrupt+0xaa/0xd0 arch/x86/kernel/irq.c:278
 </IRQ>
 <TASK>
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
RIP: 0010:finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5062
Code: c9 50 e8 19 b6 0b 00 48 83 c4 08 4c 89 f7 e8 7d 38 00 00 e9 de 04 00 00 4c 89 f7 e8 d0 d9 32 0a e8 4b e8 36 00 fb 48 8b 5d c0 <48> 8d bb f8 15 00 00 48 89 f8 48 c1 e8 03 49 be 00 00 00 00 00 fc
RSP: 0018:ffffc90003a377a8 EFLAGS: 00000286
RAX: 94ed15acce52c200 RBX: ffff88807e01da00 RCX: ffffffff947db703
RDX: dffffc0000000000 RSI: ffffffff8bcac9a0 RDI: ffffffff8c205b20
RBP: ffffc90003a377f0 R08: ffffffff8faec7af R09: 1ffffffff1f5d8f5
R10: dffffc0000000000 R11: fffffbfff1f5d8f6 R12: 1ffff110172a7ebb
R13: dffffc0000000000 R14: ffff8880b943e840 R15: ffff8880b953f5d8
 context_switch kernel/sched/core.c:5191 [inline]
 __schedule+0x1808/0x4a60 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 futex_wait_queue+0x14e/0x1d0 kernel/futex/waitwake.c:370
 __futex_wait+0x17f/0x320 kernel/futex/waitwake.c:669
 futex_wait+0x101/0x360 kernel/futex/waitwake.c:697
 do_futex+0x33b/0x560 kernel/futex/syscalls.c:102
 __do_sys_futex kernel/futex/syscalls.c:179 [inline]
 __se_sys_futex+0x3f9/0x480 kernel/futex/syscalls.c:160
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3362575b59
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:00007f33633c90f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f3362705f68 RCX: 00007f3362575b59
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f3362705f68
RBP: 00007f3362705f60 R08: 00007f33633c96c0 R09: 00007f33633c96c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3362705f6c
R13: 000000000000000b R14: 00007ffec9a21080 R15: 00007ffec9a21168
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__list_del include/linux/list.h:195 [inline]
RIP: 0010:__list_del_clearprev include/linux/list.h:209 [inline]
RIP: 0010:__dev_flush+0xe4/0x160 kernel/bpf/devmap.c:428
Code: b8 00 00 00 00 00 fc ff df 41 80 7c 05 00 00 49 89 c5 74 08 48 89 df e8 6a c3 3d 00 48 8b 2b 48 8d 5d 08 48 89 d8 48 c1 e8 03 <42> 80 3c 28 00 74 08 48 89 df e8 3d c4 3d 00 4c 89 23 4c 89 e0 48
RSP: 0018:ffffc90000a18af0 EFLAGS: 00010212
RAX: 1bd5a9d5a0000001 RBX: dead4ead00000008 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffff8880b943e868
RBP: dead4ead00000000 R08: ffff8880b943e867 R09: ffff8880b943e858
R10: dffffc0000000000 R11: ffffed1017287d0d R12: 00000000ffffffff
R13: dffffc0000000000 R14: ffff8880b943e848 R15: 1ffff11017287d09
FS:  00007f33633c96c0(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffec0000 CR3: 0000000054f40000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
   0:	b8 00 00 00 00       	mov    $0x0,%eax
   5:	00 fc                	add    %bh,%ah
   7:	ff                   	(bad)
   8:	df 41 80             	filds  -0x80(%rcx)
   b:	7c 05                	jl     0x12
   d:	00 00                	add    %al,(%rax)
   f:	49 89 c5             	mov    %rax,%r13
  12:	74 08                	je     0x1c
  14:	48 89 df             	mov    %rbx,%rdi
  17:	e8 6a c3 3d 00       	call   0x3dc386
  1c:	48 8b 2b             	mov    (%rbx),%rbp
  1f:	48 8d 5d 08          	lea    0x8(%rbp),%rbx
  23:	48 89 d8             	mov    %rbx,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1) <-- trapping instruction
  2f:	74 08                	je     0x39
  31:	48 89 df             	mov    %rbx,%rdi
  34:	e8 3d c4 3d 00       	call   0x3dc476
  39:	4c 89 23             	mov    %r12,(%rbx)
  3c:	4c 89 e0             	mov    %r12,%rax
  3f:	48                   	rex.W

---
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