syzbot


general protection fault in vidtv_mux_stop_thread

Status: upstream: reported C repro on 2024/12/29 05:56
Subsystems: media
[Documentation on labels]
Reported-by: syzbot+5e248227c80a3be8e96a@syzkaller.appspotmail.com
First crash: 8d16h, last: 3d07h
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] media: vidtv: Fix a null-ptr-deref in vidtv_mux_stop_thread 1 (1) 2024/12/29 10:50
[syzbot] [media?] general protection fault in vidtv_mux_stop_thread 1 (3) 2024/12/29 10:50
Last patch testing requests (1)
Created Duration User Patch Repo Result
2024/12/29 10:28 20m eadavis@qq.com https://github.com/ea1davis/linux md/syz OK log

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000025: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000128-0x000000000000012f]
CPU: 0 UID: 0 PID: 5842 Comm: syz-executor248 Not tainted 6.13.0-rc4-syzkaller-00012-g9b2ffa6148b1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:vidtv_mux_stop_thread+0x26/0x80 drivers/media/test-drivers/vidtv/vidtv_mux.c:471
Code: 90 90 90 90 66 0f 1f 00 55 53 48 89 fb e8 82 2e c8 f9 48 8d bb 28 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 02 7e 3b 0f b6 ab 28 01 00 00 31 ff 89 ee e8
RSP: 0018:ffffc90003f2faa8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff87cfb125
RDX: 0000000000000025 RSI: ffffffff87d120ce RDI: 0000000000000128
RBP: ffff888029b8d220 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000003 R12: ffff888029b8d188
R13: ffffffff8f590aa0 R14: ffffc9000581c5c8 R15: ffff888029a17710
FS:  00007f7eef5156c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7eef5e635c CR3: 0000000076ca6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 vidtv_stop_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:209 [inline]
 vidtv_stop_feed+0x151/0x250 drivers/media/test-drivers/vidtv/vidtv_bridge.c:252
 dmx_section_feed_stop_filtering+0x90/0x160 drivers/media/dvb-core/dvb_demux.c:1000
 dvb_dmxdev_feed_stop.isra.0+0x1ee/0x270 drivers/media/dvb-core/dmxdev.c:486
 dvb_dmxdev_filter_stop+0x22a/0x3a0 drivers/media/dvb-core/dmxdev.c:559
 dvb_dmxdev_filter_free drivers/media/dvb-core/dmxdev.c:840 [inline]
 dvb_demux_release+0x92/0x550 drivers/media/dvb-core/dmxdev.c:1246
 __fput+0x3f8/0xb60 fs/file_table.c:450
 task_work_run+0x14e/0x250 kernel/task_work.c:239
 get_signal+0x1d3/0x2610 kernel/signal.c:2790
 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7eef55b309
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 18 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:00007f7eef515218 EFLAGS: 00000246 ORIG_RAX: 0000000000000013
RAX: fffffffffffffe00 RBX: 00007f7eef5e53e8 RCX: 00007f7eef55b309
RDX: 0000000000000009 RSI: 0000000020003080 RDI: 0000000000000003
RBP: 00007f7eef5e53e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7eef5b2280
R13: 00736d79736c6c61 R14: 616b2f636f72702f R15: 0000100000000008
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:vidtv_mux_stop_thread+0x26/0x80 drivers/media/test-drivers/vidtv/vidtv_mux.c:471
Code: 90 90 90 90 66 0f 1f 00 55 53 48 89 fb e8 82 2e c8 f9 48 8d bb 28 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 02 7e 3b 0f b6 ab 28 01 00 00 31 ff 89 ee e8
RSP: 0018:ffffc90003f2faa8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff87cfb125
RDX: 0000000000000025 RSI: ffffffff87d120ce RDI: 0000000000000128
RBP: ffff888029b8d220 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000003 R12: ffff888029b8d188
R13: ffffffff8f590aa0 R14: ffffc9000581c5c8 R15: ffff888029a17710
FS:  00007f7eef5156c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7eef5e635c CR3: 0000000076ca6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	90                   	nop
   1:	90                   	nop
   2:	90                   	nop
   3:	90                   	nop
   4:	66 0f 1f 00          	nopw   (%rax)
   8:	55                   	push   %rbp
   9:	53                   	push   %rbx
   a:	48 89 fb             	mov    %rdi,%rbx
   d:	e8 82 2e c8 f9       	call   0xf9c82e94
  12:	48 8d bb 28 01 00 00 	lea    0x128(%rbx),%rdi
  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:	0f b6 04 02          	movzbl (%rdx,%rax,1),%eax <-- trapping instruction
  2e:	84 c0                	test   %al,%al
  30:	74 02                	je     0x34
  32:	7e 3b                	jle    0x6f
  34:	0f b6 ab 28 01 00 00 	movzbl 0x128(%rbx),%ebp
  3b:	31 ff                	xor    %edi,%edi
  3d:	89 ee                	mov    %ebp,%esi
  3f:	e8                   	.byte 0xe8

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/25 11:55 upstream 9b2ffa6148b1 444551c4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto general protection fault in vidtv_mux_stop_thread
2024/12/25 07:07 upstream 9b2ffa6148b1 444551c4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto general protection fault in vidtv_mux_stop_thread
2024/12/30 14:41 upstream fc033cf25e61 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto general protection fault in vidtv_mux_stop_thread
2024/12/25 05:53 upstream 9b2ffa6148b1 444551c4 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto general protection fault in vidtv_mux_stop_thread
2024/12/25 05:50 upstream 9b2ffa6148b1 444551c4 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto general protection fault in vidtv_mux_stop_thread
* Struck through repros no longer work on HEAD.