On Sat, Oct 19, 2024 at 11:44:28PM -0700, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit: 15e7d45e786a Add linux-next specific files for 20241016 > git tree: linux-next > console+strace: https://syzkaller.appspot.com/x/log.txt?x=14a8f887980000 > kernel config: https://syzkaller.appspot.com/x/.config?x=c36416f1c54640c0 > dashboard link: https://syzkaller.appspot.com/bug?extid=9446d5e0d25571e6a212 > compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1483e830580000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10560240580000 > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/cf2ad43c81cc/disk-15e7d45e.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/c85347a66a1c/vmlinux-15e7d45e.xz > kernel image: https://storage.googleapis.com/syzbot-assets/648cf8e59c13/bzImage-15e7d45e.xz > > The issue was bisected to: > > commit c5fe3ed618f995b4a903e574bf2e993cdebeefca > Author: Ricardo Ribalda <ribalda@xxxxxxxxxxxx> > Date: Thu Sep 26 05:49:58 2024 +0000 > > media: uvcvideo: Avoid race condition during unregister It looks like the issue comes from the fact that uvc_status_unregister() gets called from the error path in uvc_probe() through uvc_unregister_video(), likely for errors occuring before uvc_status_init() is called. uvc_status_unregister() should return immediately in that case. Ricardo, do you plan to look at that? > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12554240580000 > final oops: https://syzkaller.appspot.com/x/report.txt?x=11554240580000 > console output: https://syzkaller.appspot.com/x/log.txt?x=16554240580000 > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+9446d5e0d25571e6a212@xxxxxxxxxxxxxxxxxxxxxxxxx > Fixes: c5fe3ed618f9 ("media: uvcvideo: Avoid race condition during unregister") > > usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3 > usb 1-1: Product: syz > usb 1-1: Manufacturer: syz > usb 1-1: SerialNumber: syz > usb 1-1: config 0 descriptor?? > usb 1-1: Found UVC 0.00 device syz (05ac:8600) > usb 1-1: No valid video chain found. > ------------[ cut here ]------------ > DEBUG_LOCKS_WARN_ON(lock->magic != lock) > WARNING: CPU: 0 PID: 1166 at kernel/locking/mutex.c:587 __mutex_lock_common kernel/locking/mutex.c:587 [inline] > WARNING: CPU: 0 PID: 1166 at kernel/locking/mutex.c:587 __mutex_lock+0xc41/0xd70 kernel/locking/mutex.c:752 > Modules linked in: > CPU: 0 UID: 0 PID: 1166 Comm: kworker/0:2 Not tainted 6.12.0-rc3-next-20241016-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 > Workqueue: usb_hub_wq hub_event > RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:587 [inline] > RIP: 0010:__mutex_lock+0xc41/0xd70 kernel/locking/mutex.c:752 > Code: 0f b6 04 20 84 c0 0f 85 18 01 00 00 83 3d 36 20 49 04 00 75 19 90 48 c7 c7 20 b9 0a 8c 48 c7 c6 c0 b9 0a 8c e8 00 0f 81 f5 90 <0f> 0b 90 90 90 e9 bd f4 ff ff 90 0f 0b 90 e9 cf f8 ff ff 90 0f 0b > RSP: 0018:ffffc90004516980 EFLAGS: 00010246 > RAX: 44423ff48d37de00 RBX: 0000000000000000 RCX: ffff888027929e00 > RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 > RBP: ffffc90004516ad0 R08: ffffffff8155d7b2 R09: fffffbfff1cfa3e0 > R10: dffffc0000000000 R11: fffffbfff1cfa3e0 R12: dffffc0000000000 > R13: ffff88814bd82518 R14: 0000000000000000 R15: ffff88814bd824e8 > FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 000055ffca8e3610 CR3: 000000001e3f4000 CR4: 00000000003526f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > <TASK> > class_mutex_constructor include/linux/mutex.h:201 [inline] > uvc_status_suspend drivers/media/usb/uvc/uvc_status.c:375 [inline] > uvc_status_unregister+0x2f/0xe0 drivers/media/usb/uvc/uvc_status.c:297 > uvc_unregister_video+0xeb/0x1c0 drivers/media/usb/uvc/uvc_driver.c:1947 > uvc_probe+0x9135/0x98c0 drivers/media/usb/uvc/uvc_driver.c:2272 > usb_probe_interface+0x645/0xbb0 drivers/usb/core/driver.c:399 > really_probe+0x2b8/0xad0 drivers/base/dd.c:658 > __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 > driver_probe_device+0x50/0x430 drivers/base/dd.c:830 > __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958 > bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:459 > __device_attach+0x333/0x520 drivers/base/dd.c:1030 > bus_probe_device+0x189/0x260 drivers/base/bus.c:534 > device_add+0x856/0xbf0 drivers/base/core.c:3675 > usb_set_configuration+0x1976/0x1fb0 drivers/usb/core/message.c:2210 > usb_generic_driver_probe+0x88/0x140 drivers/usb/core/generic.c:254 > usb_probe_device+0x1b8/0x380 drivers/usb/core/driver.c:294 > really_probe+0x2b8/0xad0 drivers/base/dd.c:658 > __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 > driver_probe_device+0x50/0x430 drivers/base/dd.c:830 > __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958 > bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:459 > __device_attach+0x333/0x520 drivers/base/dd.c:1030 > bus_probe_device+0x189/0x260 drivers/base/bus.c:534 > device_add+0x856/0xbf0 drivers/base/core.c:3675 > usb_new_device+0x104a/0x19a0 drivers/usb/core/hub.c:2651 > hub_port_connect drivers/usb/core/hub.c:5521 [inline] > hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] > port_event drivers/usb/core/hub.c:5821 [inline] > hub_event+0x2d6d/0x5150 drivers/usb/core/hub.c:5903 > process_one_work kernel/workqueue.c:3229 [inline] > process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 > worker_thread+0x870/0xd30 kernel/workqueue.c:3391 > kthread+0x2f0/0x390 kernel/kthread.c:389 > ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > </TASK> > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > For information about bisection process see: https://goo.gl/tpsmEJ#bisection > > If the report is already addressed, let syzbot know by replying with: > #syz fix: exact-commit-title > > If you want syzbot to run the reproducer, reply with: > #syz test: git://repo/address.git branch-or-commit-hash > If you attach or paste a git patch, syzbot will apply it before testing. > > If you want to overwrite report's subsystems, reply with: > #syz set subsystems: new-subsystem > (See the list of subsystem names on the web dashboard) > > If the report is a duplicate of another one, reply with: > #syz dup: exact-subject-of-another-report > > If you want to undo deduplication, reply with: > #syz undup -- Regards, Laurent Pinchart
