syzbot


general protection fault in ptp_ioctl

Status: fixed on 2024/01/20 21:18
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+8a78ecea7ac1a2ea26e5@syzkaller.appspotmail.com
Fix commit: 8a4f030dbced ptp: Fixes a null pointer dereference in ptp_ioctl
First crash: 177d, last: 172d
Cause bisection: introduced by (bisect log) :
commit c5a445b1e9347b14752b01f1a304bd7a2f260acc
Author: Xabier Marquiegui <reibax@gmail.com>
Date: Wed Oct 11 22:39:56 2023 +0000

  ptp: support event queue reader channel masks

Crash: BUG: unable to handle kernel paging request in ptp_ioctl (log)
Repro: C syz .config
  
Discussions (5)
Title Replies (including bot) Last reply
[PATCH RESEND] ptp: Fixes a null pointer dereference in ptp_ioctl 4 (4) 2023/11/10 08:40
[PATCH] Fixes a null pointer dereference in ptp_ioctl 3 (3) 2023/11/07 19:18
[PATCH] ptp: fix null ptr deref in ptp_ioctrl 2 (2) 2023/11/06 02:12
[syzbot] [net?] general protection fault in ptp_ioctl 0 (2) 2023/11/06 00:46
Re: [syzbot] [PATCH] null pointer dereference 0 (1) 2023/11/06 00:20
Last patch testing requests (2)
Created Duration User Patch Repo Result
2023/11/06 00:46 27m lizhi.xu@windriver.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 4652b8e4f3ff OK log
2023/11/06 00:20 20m yuran.pereira@hotmail.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master OK log

Sample crash report:
general protection fault, probably for non-canonical address 0xdffffc000000020b: 0000 [#1] PREEMPT SMP KASAN
KASAN: probably user-memory-access in range [0x0000000000001058-0x000000000000105f]
CPU: 0 PID: 5053 Comm: syz-executor353 Not tainted 6.6.0-syzkaller-10396-g4652b8e4f3ff #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
RIP: 0010:ptp_ioctl+0xcb7/0x1d10 drivers/ptp/ptp_chardev.c:476
Code: 81 fe 13 3d 00 00 0f 85 9c 02 00 00 e8 c2 83 23 fa 49 8d bc 24 58 10 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 dc 0e 00 00 49 8b bc 24 58 10 00 00 ba 00 01 00
RSP: 0018:ffffc90003a37ba0 EFLAGS: 00010212
RAX: dffffc0000000000 RBX: ffff88814a78a000 RCX: ffffffff8764f81f
RDX: 000000000000020b RSI: ffffffff8765028e RDI: 0000000000001058
RBP: ffffc90003a37ec0 R08: 0000000000000005 R09: ffffc90003a37c40
R10: 0000000000003d13 R11: 0000000000000000 R12: 0000000000000000
R13: ffffc90003a37c80 R14: 0000000000003d13 R15: ffffffff92ac78e8
FS:  00005555569a9380(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000040 CR3: 0000000076e09000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 posix_clock_ioctl+0xf8/0x160 kernel/time/posix-clock.c:86
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl fs/ioctl.c:857 [inline]
 __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f710ac4a2a9
Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffda288c4c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ffda288c698 RCX: 00007f710ac4a2a9
RDX: 0000000000000000 RSI: 0000000000003d13 RDI: 0000000000000003
RBP: 00007f710acbd610 R08: 00007ffda288c698 R09: 00007ffda288c698
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffda288c688 R14: 0000000000000001 R15: 0000000000000001
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ptp_ioctl+0xcb7/0x1d10 drivers/ptp/ptp_chardev.c:476
Code: 81 fe 13 3d 00 00 0f 85 9c 02 00 00 e8 c2 83 23 fa 49 8d bc 24 58 10 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 dc 0e 00 00 49 8b bc 24 58 10 00 00 ba 00 01 00
RSP: 0018:ffffc90003a37ba0 EFLAGS: 00010212
RAX: dffffc0000000000 RBX: ffff88814a78a000 RCX: ffffffff8764f81f
RDX: 000000000000020b RSI: ffffffff8765028e RDI: 0000000000001058
RBP: ffffc90003a37ec0 R08: 0000000000000005 R09: ffffc90003a37c40
R10: 0000000000003d13 R11: 0000000000000000 R12: 0000000000000000
R13: ffffc90003a37c80 R14: 0000000000003d13 R15: ffffffff92ac78e8
FS:  00005555569a9380(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000005fdeb8 CR3: 0000000076e09000 CR4: 0000000000350ef0
----------------
Code disassembly (best guess):
   0:	81 fe 13 3d 00 00    	cmp    $0x3d13,%esi
   6:	0f 85 9c 02 00 00    	jne    0x2a8
   c:	e8 c2 83 23 fa       	call   0xfa2383d3
  11:	49 8d bc 24 58 10 00 	lea    0x1058(%r12),%rdi
  18:	00
  19:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  20:	fc ff df
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	0f 85 dc 0e 00 00    	jne    0xf10
  34:	49 8b bc 24 58 10 00 	mov    0x1058(%r12),%rdi
  3b:	00
  3c:	ba                   	.byte 0xba
  3d:	00 01                	add    %al,(%rcx)

Crashes (8):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/03 13:08 upstream 4652b8e4f3ff c4ac074c .config strace log report syz C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root general protection fault in ptp_ioctl
2023/11/07 00:19 upstream d2f51b3516da 78fae24e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root general protection fault in ptp_ioctl
2023/11/03 12:51 upstream 4652b8e4f3ff c4ac074c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root general protection fault in ptp_ioctl
2023/11/02 14:06 upstream 21e80f3841c0 c5562b0d .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in ptp_ioctl
2023/11/04 21:47 linux-next e27090b1413f 500bfdc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ptp_ioctl
2023/11/04 03:48 linux-next e27090b1413f 500bfdc4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ptp_ioctl
2023/11/03 11:14 linux-next e27090b1413f c4ac074c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ptp_ioctl
2023/11/01 18:59 linux-next fa7d0c172786 69904c9f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root general protection fault in ptp_ioctl
* Struck through repros no longer work on HEAD.