On Fri, 10 Jan 2025 at 14:44, syzbot <syzbot+f49137d13c521670729e@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hello, > > syzbot found the following issue on: > > HEAD commit: f1a2241778d9 usb: typec: ucsi: Implement ChromeOS UCSI dri.. > git tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing > console output: https://syzkaller.appspot.com/x/log.txt?x=17424edf980000 > kernel config: https://syzkaller.appspot.com/x/.config?x=e27867f71e8bc406 > dashboard link: https://syzkaller.appspot.com/bug?extid=f49137d13c521670729e > compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 > > Unfortunately, I don't have any reproducer for this issue yet. > > Downloadable assets: > disk image: https://storage.googleapis.com/syzbot-assets/637d8b06e4f6/disk-f1a22417.raw.xz > vmlinux: https://storage.googleapis.com/syzbot-assets/c3511b47d743/vmlinux-f1a22417.xz > kernel image: https://storage.googleapis.com/syzbot-assets/d923c98af39e/bzImage-f1a22417.xz > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+f49137d13c521670729e@xxxxxxxxxxxxxxxxxxxxxxxxx > > ================================================================== > BUG: KASAN: use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:172 [inline] > BUG: KASAN: use-after-free in __mutex_lock_common kernel/locking/mutex.c:667 [inline] > BUG: KASAN: use-after-free in __mutex_lock+0x96b/0xa60 kernel/locking/mutex.c:735 > Read of size 8 at addr ffff888123869b30 by task v4l_id/28455 > > CPU: 0 UID: 0 PID: 28455 Comm: v4l_id Not tainted 6.13.0-rc4-syzkaller-00080-gf1a2241778d9 #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 > Call Trace: > <TASK> > __dump_stack lib/dump_stack.c:94 [inline] > dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 > print_address_description mm/kasan/report.c:378 [inline] > print_report+0xc3/0x620 mm/kasan/report.c:489 > kasan_report+0xd9/0x110 mm/kasan/report.c:602 > __mutex_waiter_is_first kernel/locking/mutex.c:172 [inline] > __mutex_lock_common kernel/locking/mutex.c:667 [inline] > __mutex_lock+0x96b/0xa60 kernel/locking/mutex.c:735 > em28xx_v4l2_open+0x22c/0x7e0 drivers/media/usb/em28xx/em28xx-video.c:2150 Does the file hold reference to the device? I am not an expert on this code, but: static const struct video_device em28xx_video_template = { .... .release = video_device_release_empty, }; void video_device_release_empty(struct video_device *vdev) { /* Do nothing */ /* Only valid when the video_device struct is a static. */ } And it does not look like a static device. > v4l2_open+0x222/0x490 drivers/media/v4l2-core/v4l2-dev.c:429 > chrdev_open+0x237/0x6a0 fs/char_dev.c:414 > do_dentry_open+0x6cb/0x1390 fs/open.c:945 > vfs_open+0x82/0x3f0 fs/open.c:1075 > do_open fs/namei.c:3828 [inline] > path_openat+0x1e6a/0x2d60 fs/namei.c:3987 > do_filp_open+0x20c/0x470 fs/namei.c:4014 > do_sys_openat2+0x17a/0x1e0 fs/open.c:1402 > do_sys_open fs/open.c:1417 [inline] > __do_sys_openat fs/open.c:1433 [inline] > __se_sys_openat fs/open.c:1428 [inline] > __x64_sys_openat+0x175/0x210 fs/open.c:1428 > do_syscall_x64 arch/x86/entry/common.c:52 [inline] > do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 > entry_SYSCALL_64_after_hwframe+0x77/0x7f > RIP: 0033:0x7f9e668f39a4 > Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83 > RSP: 002b:00007ffc1b3c97a0 EFLAGS: 00000246 > ORIG_RAX: 0000000000000101 > RAX: ffffffffffffffda RBX: 00007ffc1b3c99b8 RCX: 00007f9e668f39a4 > RDX: 0000000000000000 RSI: 00007ffc1b3caf22 RDI: 00000000ffffff9c > RBP: 00007ffc1b3caf22 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 > R13: 00007ffc1b3c99d0 R14: 000055a2b40c3670 R15: 00007f9e66d42a80 > </TASK> > > The buggy address belongs to the physical page: > page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888100000004 pfn:0x123869 > flags: 0x200000000000000(node=0|zone=2) > raw: 0200000000000000 0000000000000000 ffffffffffffffff 0000000000000000 > raw: ffff888100000004 0000000000000000 00000000ffffffff 0000000000000000 > page dumped because: kasan: bad access detected > page_owner tracks the page as freed > page last allocated via order 2, migratetype Unmovable, gfp_mask 0x40dc0(GFP_KERNEL|__GFP_COMP|__GFP_ZERO), pid 9, tgid 9 (kworker/0:1), ts 2999230831583, free_ts 3004034271205 > set_page_owner include/linux/page_owner.h:32 [inline] > post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1558 > prep_new_page mm/page_alloc.c:1566 [inline] > get_page_from_freelist+0xe76/0x2b90 mm/page_alloc.c:3476 > __alloc_pages_noprof+0x21c/0x22a0 mm/page_alloc.c:4753 > __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] > alloc_pages_node_noprof include/linux/gfp.h:296 [inline] > ___kmalloc_large_node+0x84/0x1b0 mm/slub.c:4243 > __kmalloc_large_noprof+0x1c/0x70 mm/slub.c:4260 > kmalloc_noprof include/linux/slab.h:898 [inline] > kzalloc_noprof include/linux/slab.h:1037 [inline] > em28xx_usb_probe+0x1db/0x3720 drivers/media/usb/em28xx/em28xx-cards.c:3908 > usb_probe_interface+0x300/0x9c0 drivers/usb/core/driver.c:396 > call_driver_probe drivers/base/dd.c:579 [inline] > really_probe+0x23e/0xa90 drivers/base/dd.c:658 > __driver_probe_device+0x1de/0x440 drivers/base/dd.c:800 > driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:830 > __device_attach_driver+0x1df/0x310 drivers/base/dd.c:958 > bus_for_each_drv+0x157/0x1e0 drivers/base/bus.c:459 > __device_attach+0x1e8/0x4b0 drivers/base/dd.c:1030 > bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:534 > device_add+0x114b/0x1a70 drivers/base/core.c:3665 > usb_set_configuration+0x10cb/0x1c50 drivers/usb/core/message.c:2210 > page last free pid 9 tgid 9 stack trace: > reset_page_owner include/linux/page_owner.h:25 [inline] > free_pages_prepare mm/page_alloc.c:1127 [inline] > free_unref_page+0x661/0xe40 mm/page_alloc.c:2659 > __folio_put+0x1e8/0x2d0 mm/swap.c:112 > em28xx_free_device drivers/media/usb/em28xx/em28xx-cards.c:3566 [inline] > kref_put include/linux/kref.h:65 [inline] > em28xx_usb_disconnect+0x3a5/0x610 drivers/media/usb/em28xx/em28xx-cards.c:4207 > usb_unbind_interface+0x1e2/0x960 drivers/usb/core/driver.c:458 > device_remove drivers/base/dd.c:569 [inline] > device_remove+0x122/0x170 drivers/base/dd.c:561 > __device_release_driver drivers/base/dd.c:1273 [inline] > device_release_driver_internal+0x44a/0x610 drivers/base/dd.c:1296 > bus_remove_device+0x22f/0x420 drivers/base/bus.c:576 > device_del+0x396/0x9f0 drivers/base/core.c:3854 > usb_disable_device+0x36c/0x7f0 drivers/usb/core/message.c:1418 > usb_disconnect+0x2e1/0x920 drivers/usb/core/hub.c:2304 > hub_port_connect drivers/usb/core/hub.c:5361 [inline] > hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] > port_event drivers/usb/core/hub.c:5821 [inline] > hub_event+0x1bed/0x4f40 drivers/usb/core/hub.c:5903 > process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229 > process_scheduled_works kernel/workqueue.c:3310 [inline] > worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 > kthread+0x2c1/0x3a0 kernel/kthread.c:389 > ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > > Memory state around the buggy address: > ffff888123869a00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff > ffff888123869a80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff > >ffff888123869b00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff > ^ > ffff888123869b80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff > ffff888123869c00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff > ================================================================== > > > --- > 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. > > If the report is already addressed, let syzbot know by replying with: > #syz fix: exact-commit-title > > 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 > > -- > You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion visit https://groups.google.com/d/msgid/syzkaller-bugs/67812439.050a0220.216c54.0010.GAE%40google.com.
