syzbot


KASAN: use-after-free Read in v4l2_fh_del

Status: closed as dup on 2019/08/13 12:59
Subsystems: media
[Documentation on labels]
Reported-by: syzbot+d53275bc1af5eb01bfff@syzkaller.appspotmail.com
First crash: 1793d, last: 1793d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
KASAN: use-after-free Read in v4l2_ioctl usb media C 33 1729d 1810d
Discussions (3)
Title Replies (including bot) Last reply
KASAN: use-after-free Read in v4l2_fh_del 1 (2) 2019/08/13 12:58
Reminder: 35 open syzbot bugs in media subsystem 1 (1) 2019/07/24 01:39
Reminder: 28 open syzbot bugs in media subsystem 1 (1) 2019/06/27 03:53

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x2930/0x37c0 kernel/locking/lockdep.c:3573
Read of size 8 at addr ffff88806b57ec90 by task v4l_id/7959

CPU: 0 PID: 7959 Comm: v4l_id Not tainted 5.1.0-rc3-319004-g43151d6 #6
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xe8/0x16e lib/dump_stack.c:113
 print_address_description+0x6c/0x236 mm/kasan/report.c:187
 kasan_report.cold+0x1a/0x3c mm/kasan/report.c:317
 __lock_acquire+0x2930/0x37c0 kernel/locking/lockdep.c:3573
 lock_acquire+0x10d/0x2f0 kernel/locking/lockdep.c:4211
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x44/0x60 kernel/locking/spinlock.c:152
 v4l2_fh_del+0x4e/0x270 drivers/media/v4l2-core/v4l2-fh.c:81
 v4l2_fh_release+0x46/0x70 drivers/media/v4l2-core/v4l2-fh.c:104
 v4l2_release+0x2f0/0x390 drivers/media/v4l2-core/v4l2-dev.c:459
 __fput+0x2df/0x8c0 fs/file_table.c:278
 task_work_run+0x149/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x243/0x270 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x40c/0x4f0 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fd157cde2b0
Code: 40 75 0b 31 c0 48 83 c4 08 e9 0c ff ff ff 48 8d 3d c5 32 08 00 e8 c0 07 02 00 83 3d 45 a3 2b 00 00 75 10 b8 03 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ce 8a 01 00 48 89 04 24
RSP: 002b:00007ffcf08bde38 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 00007fd157cde2b0
RDX: 0000000000000013 RSI: 0000000080685600 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000400884
R13: 00007ffcf08bdf90 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 17:
 set_track mm/kasan/common.c:87 [inline]
 __kasan_kmalloc mm/kasan/common.c:497 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:470
 slab_post_alloc_hook mm/slab.h:437 [inline]
 slab_alloc_node mm/slub.c:2756 [inline]
 __kmalloc_node_track_caller+0xf3/0x320 mm/slub.c:4372
 alloc_dr drivers/base/devres.c:103 [inline]
 devm_kmalloc+0x8c/0x190 drivers/base/devres.c:793
 devm_kzalloc include/linux/device.h:679 [inline]
 usb_raremono_probe+0x34/0x235 drivers/media/radio/radio-raremono.c:298
 usb_probe_interface+0x31d/0x820 drivers/usb/core/driver.c:361
 really_probe+0x2da/0xb10 drivers/base/dd.c:509
 driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
 __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
 __device_attach+0x223/0x3a0 drivers/base/dd.c:844
 bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
 device_add+0xad2/0x16e0 drivers/base/core.c:2106
 usb_set_configuration+0xdf7/0x1740 drivers/usb/core/message.c:2023
 generic_probe+0xa2/0xda drivers/usb/core/generic.c:210
 usb_probe_device+0xc0/0x150 drivers/usb/core/driver.c:266
 really_probe+0x2da/0xb10 drivers/base/dd.c:509
 driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
 __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
 __device_attach+0x223/0x3a0 drivers/base/dd.c:844
 bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
 device_add+0xad2/0x16e0 drivers/base/core.c:2106
 usb_new_device.cold+0x537/0xccf drivers/usb/core/hub.c:2534
 hub_port_connect drivers/usb/core/hub.c:5089 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
 port_event drivers/usb/core/hub.c:5350 [inline]
 hub_event+0x138e/0x3b00 drivers/usb/core/hub.c:5432
 process_one_work+0x90f/0x1580 kernel/workqueue.c:2269
 process_scheduled_works kernel/workqueue.c:2331 [inline]
 worker_thread+0x7b0/0xe20 kernel/workqueue.c:2417
 kthread+0x313/0x420 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

Freed by task 17:
 set_track mm/kasan/common.c:87 [inline]
 __kasan_slab_free+0x130/0x180 mm/kasan/common.c:459
 slab_free_hook mm/slub.c:1429 [inline]
 slab_free_freelist_hook+0x5e/0x140 mm/slub.c:1456
 slab_free mm/slub.c:3003 [inline]
 kfree+0xce/0x290 mm/slub.c:3958
 release_nodes+0x4ac/0x920 drivers/base/devres.c:508
 devres_release_all+0x79/0xc8 drivers/base/devres.c:529
 __device_release_driver drivers/base/dd.c:1086 [inline]
 device_release_driver_internal+0x23a/0x4f0 drivers/base/dd.c:1113
 bus_remove_device+0x302/0x5c0 drivers/base/bus.c:556
 device_del+0x467/0xb90 drivers/base/core.c:2269
 usb_disable_device+0x242/0x790 drivers/usb/core/message.c:1237
 usb_disconnect+0x298/0x870 drivers/usb/core/hub.c:2197
 hub_port_connect drivers/usb/core/hub.c:4940 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
 port_event drivers/usb/core/hub.c:5350 [inline]
 hub_event+0xcd2/0x3b00 drivers/usb/core/hub.c:5432
 process_one_work+0x90f/0x1580 kernel/workqueue.c:2269
 process_scheduled_works kernel/workqueue.c:2331 [inline]
 worker_thread+0x7b0/0xe20 kernel/workqueue.c:2417
 kthread+0x313/0x420 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

The buggy address belongs to the object at ffff88806b57e600
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 1680 bytes inside of
 4096-byte region [ffff88806b57e600, ffff88806b57f600)
The buggy address belongs to the page:
page:ffffea0001ad5e00 count:1 mapcount:0 mapping:ffff88812c3f4600 index:0x0 compound_mapcount: 0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 0000000000000000 0000000100000001 ffff88812c3f4600
raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88806b57eb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88806b57ec00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88806b57ec80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff88806b57ed00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88806b57ed80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/05/01 06:05 https://github.com/google/kasan.git usb-fuzzer 43151d6c3fce 618456b4 .config console log report ci2-upstream-usb
* Struck through repros no longer work on HEAD.