lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <695ec9af.050a0220.1c677c.037d.GAE@google.com>
Date: Wed, 07 Jan 2026 13:01:35 -0800
From: syzbot ci <syzbot+cicac8180258d8bceb@...kaller.appspotmail.com>
To: andrii@...nel.org, ast@...nel.org, bpf@...r.kernel.org, 
	daniel@...earbox.net, davem@...emloft.net, dxu@...uu.xyz, eddyz87@...il.com, 
	edumazet@...gle.com, electronlsr@...il.com, ftyghome@...il.com, 
	gplhust955@...il.com, haoluo@...gle.com, haoran.ni.cs@...il.com, 
	horms@...nel.org, john.fastabend@...il.com, jolsa@...nel.org, 
	kpsingh@...nel.org, kuba@...nel.org, linux-kernel@...r.kernel.org, 
	linux-trace-kernel@...r.kernel.org, martin.lau@...ux.dev, 
	mathieu.desnoyers@...icios.com, mattbobrowski@...gle.com, mhiramat@...nel.org, 
	netdev@...r.kernel.org, pabeni@...hat.com, rostedt@...dmis.org, 
	sdf@...ichev.me, song@...nel.org, yonghong.song@...ux.dev
Cc: syzbot@...ts.linux.dev, syzkaller-bugs@...glegroups.com
Subject: [syzbot ci] Re: bpf: Fix memory access flags in helper prototypes

syzbot ci has tested the following series

[v1] bpf: Fix memory access flags in helper prototypes
https://lore.kernel.org/all/20260107-helper_proto-v1-0-e387e08271cc@gmail.com
* [PATCH bpf 1/2] bpf: Fix memory access flags in helper prototypes
* [PATCH bpf 2/2] bpf: Require ARG_PTR_TO_MEM with memory flag

and found the following issue:
WARNING in check_helper_call

Full report is available here:
https://ci.syzbot.org/series/020c2fa8-b95d-4273-9bc0-2f82fa714a8e

***

WARNING in check_helper_call

tree:      bpf
URL:       https://kernel.googlesource.com/pub/scm/linux/kernel/git/bpf/bpf.git
base:      ab86d0bf01f6d0e37fd67761bb62918321b64efc
arch:      amd64
compiler:  Debian clang version 21.1.8 (++20251202083448+f68f64eb8130-1~exp1~20251202083504.46), Debian LLD 21.1.8
config:    https://ci.syzbot.org/builds/9a24b0e7-35e4-4718-b939-3b210b6b5126/config
C repro:   https://ci.syzbot.org/findings/8fcbdcf8-4480-46d8-b7a8-f1de9401a8ac/c_repro
syz repro: https://ci.syzbot.org/findings/8fcbdcf8-4480-46d8-b7a8-f1de9401a8ac/syz_repro

------------[ cut here ]------------
verifier bug: incorrect func proto bpf_tcp_raw_check_syncookie_ipv6#207
WARNING: kernel/bpf/verifier.c:11546 at check_helper_call+0xc00/0x6e10 kernel/bpf/verifier.c:11546, CPU#0: syz.0.17/5981
Modules linked in:
CPU: 0 UID: 0 PID: 5981 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:check_helper_call+0xc16/0x6e10 kernel/bpf/verifier.c:11546
Code: ef e6 ff 49 bf 00 00 00 00 00 fc ff df 48 8d 1d a0 c2 ea 0d 44 8b 64 24 24 44 89 e7 e8 d3 32 0c 00 48 89 df 48 89 c6 44 89 e2 <67> 48 0f b9 3a 49 81 c6 80 08 00 00 44 89 e7 e8 b6 32 0c 00 4c 89
RSP: 0018:ffffc90007116fa0 EFLAGS: 00010246
RAX: ffffffff8b934740 RBX: ffffffff8fc645d0 RCX: dffffc0000000000
RDX: 00000000000000cf RSI: ffffffff8b934740 RDI: ffffffff8fc645d0
RBP: ffffc900071171b0 R08: ffff88816b42ba80 R09: 0000000000000002
R10: 0000000000000004 R11: 0000000000000000 R12: 00000000000000cf
R13: f8f8f8f8f8f8f8f8 R14: ffff888112440000 R15: dffffc0000000000
FS:  000055557af7b500(0000) GS:ffff88818e40e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd892207dac CR3: 0000000161682000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 do_check_insn kernel/bpf/verifier.c:20417 [inline]
 do_check+0x99eb/0xec30 kernel/bpf/verifier.c:20598
 do_check_common+0x19cc/0x25b0 kernel/bpf/verifier.c:23882
 do_check_main kernel/bpf/verifier.c:23965 [inline]
 bpf_check+0x5f0d/0x1c4a0 kernel/bpf/verifier.c:25272
 bpf_prog_load+0x1484/0x1ae0 kernel/bpf/syscall.c:3088
 __sys_bpf+0x570/0x920 kernel/bpf/syscall.c:6164
 __do_sys_bpf kernel/bpf/syscall.c:6274 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6272 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6272
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd891f9acb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffee24b6bb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fd892205fa0 RCX: 00007fd891f9acb9
RDX: 0000000000000094 RSI: 0000200000000300 RDI: 0000000000000005
RBP: 00007fd892008bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd892205fac R14: 00007fd892205fa0 R15: 00007fd892205fa0
 </TASK>
----------------
Code disassembly (best guess):
   0:	ef                   	out    %eax,(%dx)
   1:	e6 ff                	out    %al,$0xff
   3:	49 bf 00 00 00 00 00 	movabs $0xdffffc0000000000,%r15
   a:	fc ff df
   d:	48 8d 1d a0 c2 ea 0d 	lea    0xdeac2a0(%rip),%rbx        # 0xdeac2b4
  14:	44 8b 64 24 24       	mov    0x24(%rsp),%r12d
  19:	44 89 e7             	mov    %r12d,%edi
  1c:	e8 d3 32 0c 00       	call   0xc32f4
  21:	48 89 df             	mov    %rbx,%rdi
  24:	48 89 c6             	mov    %rax,%rsi
  27:	44 89 e2             	mov    %r12d,%edx
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	49 81 c6 80 08 00 00 	add    $0x880,%r14
  36:	44 89 e7             	mov    %r12d,%edi
  39:	e8 b6 32 0c 00       	call   0xc32f4
  3e:	4c                   	rex.WR
  3f:	89                   	.byte 0x89


***

If these findings have caused you to resend the series or submit a
separate fix, please add the following tag to your commit message:
  Tested-by: syzbot@...kaller.appspotmail.com

---
This report is generated by a bot. It may contain errors.
syzbot ci engineers can be reached at syzkaller@...glegroups.com.

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ