syzbot


BUG: unable to handle kernel NULL pointer dereference in bpf_obj_name_cpy

Status: auto-obsoleted due to no activity on 2023/04/01 07:02
Subsystems: bpf
[Documentation on labels]
Reported-by: syzbot+d4a3562dda559c6135ba@syzkaller.appspotmail.com
First crash: 660d, last: 660d

Sample crash report:
BUG: kernel NULL pointer dereference, address: 0000000000000470
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 4a9e8067 P4D 4a9e8067 PUD 5285b067 PMD 0 
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 23526 Comm: syz-executor.5 Not tainted 6.2.0-rc6-next-20230131-syzkaller-09515-g80bd9028feca #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
RIP: 0010:memset_erms+0xd/0x20 arch/x86/lib/memset_64.S:66
Code: 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 66 0f 1f 00 49 89 f9 40 88 f0 48 89 d1 <f3> aa 4c 89 c8 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 66 0f 1f
RSP: 0018:ffffc90008d0fac8 EFLAGS: 00010246
RAX: 0000000000000800 RBX: ffffc90008d0fe28 RCX: 0000000000000010
RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000470
RBP: ffffc90008d0fe18 R08: 0000000000000004 R09: 0000000000000470
R10: 000000000005f366 R11: 0000000000000000 R12: 0000000000000470
R13: ffffc90008ced000 R14: 0000000000000010 R15: ffff888054cd6000
FS:  00007fa734bfd700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000470 CR3: 000000007cdab000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 bpf_obj_name_cpy+0x3b/0x1a0 kernel/bpf/syscall.c:961
 bpf_prog_load+0x1686/0x21d0 kernel/bpf/syscall.c:2611
 __sys_bpf+0x1435/0x5100 kernel/bpf/syscall.c:4977
 __do_sys_bpf kernel/bpf/syscall.c:5081 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5079 [inline]
 __x64_sys_bpf+0x79/0xc0 kernel/bpf/syscall.c:5079
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fa73e48c0c9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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:00007fa734bfd168 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fa73e5ac120 RCX: 00007fa73e48c0c9
RDX: 0000000000000080 RSI: 0000000020000900 RDI: 0000000000000005
RBP: 00007fa73e4e7ae9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffacc80d0f R14: 00007fa734bfd300 R15: 0000000000022000
 </TASK>
Modules linked in:
CR2: 0000000000000470
---[ end trace 0000000000000000 ]---
RIP: 0010:memset_erms+0xd/0x20 arch/x86/lib/memset_64.S:66
Code: 01 48 0f af c6 f3 48 ab 89 d1 f3 aa 4c 89 c8 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 66 0f 1f 00 49 89 f9 40 88 f0 48 89 d1 <f3> aa 4c 89 c8 c3 66 66 2e 0f 1f 84 00 00 00 00 00 66 90 66 0f 1f
RSP: 0018:ffffc90008d0fac8 EFLAGS: 00010246
RAX: 0000000000000800 RBX: ffffc90008d0fe28 RCX: 0000000000000010
RDX: 0000000000000010 RSI: 0000000000000000 RDI: 0000000000000470
RBP: ffffc90008d0fe18 R08: 0000000000000004 R09: 0000000000000470
R10: 000000000005f366 R11: 0000000000000000 R12: 0000000000000470
R13: ffffc90008ced000 R14: 0000000000000010 R15: ffff888054cd6000
FS:  00007fa734bfd700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000470 CR3: 000000007cdab000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	48 0f af c6          	imul   %rsi,%rax
   4:	f3 48 ab             	rep stos %rax,%es:(%rdi)
   7:	89 d1                	mov    %edx,%ecx
   9:	f3 aa                	rep stos %al,%es:(%rdi)
   b:	4c 89 c8             	mov    %r9,%rax
   e:	c3                   	retq
   f:	66 66 2e 0f 1f 84 00 	data16 nopw %cs:0x0(%rax,%rax,1)
  16:	00 00 00 00
  1a:	66 90                	xchg   %ax,%ax
  1c:	66 0f 1f 00          	nopw   (%rax)
  20:	49 89 f9             	mov    %rdi,%r9
  23:	40 88 f0             	mov    %sil,%al
  26:	48 89 d1             	mov    %rdx,%rcx
* 29:	f3 aa                	rep stos %al,%es:(%rdi) <-- trapping instruction
  2b:	4c 89 c8             	mov    %r9,%rax
  2e:	c3                   	retq
  2f:	66 66 2e 0f 1f 84 00 	data16 nopw %cs:0x0(%rax,%rax,1)
  36:	00 00 00 00
  3a:	66 90                	xchg   %ax,%ax
  3c:	66                   	data16
  3d:	0f                   	.byte 0xf
  3e:	1f                   	(bad)

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/01/31 07:02 linux-next 80bd9028feca 9dfcf09c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root BUG: unable to handle kernel NULL pointer dereference in bpf_obj_name_cpy
* Struck through repros no longer work on HEAD.