Subject: [syzbot] [bpf?] [net?] general protection fault in dev_map_enqueue (2)

From: syzbot <[email-masked]>
Date: Sun, 26 May 2024 17:44:24 -0700

Hello,

syzbot found the following issue on:

HEAD commit:    8f6a15f095a6 Merge tag 'cocci-for-6.10' of git://git.kerne..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=136bd8fc980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=6be91306a8917025
dashboard link: https://syzkaller.appspot.com/bug?extid=cca39e6e84a367a7e6f6
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/02867060d65d/disk-8f6a15f0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4bb75fbf6fb1/vmlinux-8f6a15f0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/fd38cadddf33/bzImage-8f6a15f0.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 0xdffffc000000003b: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x00000000000001d8-0x00000000000001df]
CPU: 0 PID: 12830 Comm: syz-executor.1 Not tainted 6.9.0-syzkaller-10323-g8f6a15f095a6 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
RIP: 0010:__xdp_enqueue kernel/bpf/devmap.c:484 [inline]
RIP: 0010:dev_map_enqueue+0x70/0x3e0 kernel/bpf/devmap.c:541
Code: c5 18 48 89 e8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 ef e8 b2 10 3a 00 48 8b 5d 00 49 8d af d8 01 00 00 48 89 e8 48 c1 e8 03 <42> 0f b6 04 30 84 c0 0f 85 3a 02 00 00 8b 6d 00 89 ee 83 e6 04 31
RSP: 0018:ffffc900031ff678 EFLAGS: 00010202
RAX: 000000000000003b RBX: ffff888023efa078 RCX: 0000000000040000
RDX: ffffc90015e01000 RSI: 0000000000000ba1 RDI: 0000000000000ba2
RBP: 00000000000001d9 R08: ffffffff895b0946 R09: ffffffff895b0903
R10: 0000000000000004 R11: ffff888020d73c00 R12: ffff888058f06000
R13: ffff888021fff070 R14: dffffc0000000000 R15: 0000000000000001
FS:  00007f9f791576c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30823000 CR3: 000000002e298000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __xdp_do_redirect_frame net/core/filter.c:4397 [inline]
 xdp_do_redirect_frame+0x2a6/0x660 net/core/filter.c:4451
 xdp_test_run_batch net/bpf/test_run.c:336 [inline]
 bpf_test_run_xdp_live+0xe60/0x1e60 net/bpf/test_run.c:384
 bpf_prog_test_run_xdp+0x80e/0x11b0 net/bpf/test_run.c:1275
 bpf_prog_test_run+0x33a/0x3b0 kernel/bpf/syscall.c:4291
 __sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5705
 __do_sys_bpf kernel/bpf/syscall.c:5794 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5792 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5792
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9f7847cee9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9f791570c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f9f785ac050 RCX: 00007f9f7847cee9
RDX: 0000000000000048 RSI: 00000000200000c0 RDI: 000000000000000a
RBP: 00007f9f784c949e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f9f785ac050 R15: 00007ffc7dc03298
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:__xdp_enqueue kernel/bpf/devmap.c:484 [inline]
RIP: 0010:dev_map_enqueue+0x70/0x3e0 kernel/bpf/devmap.c:541
Code: c5 18 48 89 e8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 ef e8 b2 10 3a 00 48 8b 5d 00 49 8d af d8 01 00 00 48 89 e8 48 c1 e8 03 <42> 0f b6 04 30 84 c0 0f 85 3a 02 00 00 8b 6d 00 89 ee 83 e6 04 31
RSP: 0018:ffffc900031ff678 EFLAGS: 00010202
RAX: 000000000000003b RBX: ffff888023efa078 RCX: 0000000000040000
RDX: ffffc90015e01000 RSI: 0000000000000ba1 RDI: 0000000000000ba2
RBP: 00000000000001d9 R08: ffffffff895b0946 R09: ffffffff895b0903
R10: 0000000000000004 R11: ffff888020d73c00 R12: ffff888058f06000
R13: ffff888021fff070 R14: dffffc0000000000 R15: 0000000000000001
FS:  00007f9f791576c0(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b30823000 CR3: 000000002e298000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	18 48 89             	sbb    %cl,-0x77(%rax)
   3:	e8 48 c1 e8 03       	call   0x3e8c150
   8:	42 80 3c 30 00       	cmpb   $0x0,(%rax,%r14,1)
   d:	74 08                	je     0x17
   f:	48 89 ef             	mov    %rbp,%rdi
  12:	e8 b2 10 3a 00       	call   0x3a10c9
  17:	48 8b 5d 00          	mov    0x0(%rbp),%rbx
  1b:	49 8d af d8 01 00 00 	lea    0x1d8(%r15),%rbp
  22:	48 89 e8             	mov    %rbp,%rax
  25:	48 c1 e8 03          	shr    $0x3,%rax
* 29:	42 0f b6 04 30       	movzbl (%rax,%r14,1),%eax <-- trapping instruction
  2e:	84 c0                	test   %al,%al
  30:	0f 85 3a 02 00 00    	jne    0x270
  36:	8b 6d 00             	mov    0x0(%rbp),%ebp
  39:	89 ee                	mov    %ebp,%esi
  3b:	83 e6 04             	and    $0x4,%esi
  3e:	31                   	.byte 0x31

---
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