KASAN: use-after-free Write in usbvision_scratch_alloc

Status: closed as dup on 2019/09/20 15:34
Subsystems: media
[Documentation on labels]
Reported-by: syzbot+fa317310495b601f2c3e@syzkaller.appspotmail.com
First crash: 2555d, last: 2431d
▶ ▼ Duplicate of
Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported
general protection fault in usb_set_interface usb 2 C 3 2502d 2504d
▶ ▼ Discussions (2)
Title Replies (including bot) Last reply
KASAN: use-after-free Write in usbvision_scratch_alloc 1 (2) 2019/09/20 15:34
Reminder: 52 active syzbot reports in usb subsystem 4 (4) 2019/09/19 19:01

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in usbvision_scratch_alloc+0x8c/0xa0 drivers/media/usb/usbvision/usbvision-core.c:350
Write of size 8 at addr ffff8881c8de1b80 by task v4l_id/5794

CPU: 0 PID: 5794 Comm: v4l_id Not tainted 5.4.0-rc6-syzkaller #0
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+0xca/0x13e lib/dump_stack.c:113
 print_address_description.constprop.0+0x36/0x50 mm/kasan/report.c:374
 __kasan_report.cold+0x1a/0x33 mm/kasan/report.c:506
 kasan_report+0xe/0x20 mm/kasan/common.c:634
 usbvision_scratch_alloc+0x8c/0xa0 drivers/media/usb/usbvision/usbvision-core.c:350
 usbvision_v4l2_open+0x148/0x2f0 drivers/media/usb/usbvision/usbvision-video.c:325
 v4l2_open+0x20f/0x3d0 drivers/media/v4l2-core/v4l2-dev.c:423
 chrdev_open+0x219/0x5c0 fs/char_dev.c:414
 do_dentry_open+0x494/0x1120 fs/open.c:797
 do_last fs/namei.c:3408 [inline]
 path_openat+0x1430/0x3ff0 fs/namei.c:3525
 do_filp_open+0x1a1/0x280 fs/namei.c:3555
 do_sys_open+0x3c0/0x580 fs/open.c:1097
 do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f7bf774f120
Code: 48 8b 15 1b 4d 2b 00 f7 d8 64 89 02 83 c8 ff c3 90 90 90 90 90 90 90 90 90 90 83 3d d5 a4 2b 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 5e 8c 01 00 48 89 04 24
RSP: 002b:00007ffc499ad478 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007ffc499ad5d8 RCX: 00007f7bf774f120
RDX: 00007f7bf7a04138 RSI: 0000000000000000 RDI: 00007ffc499adf1c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000400884
R13: 00007ffc499ad5d0 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 2135:
 save_stack+0x1b/0x80 mm/kasan/common.c:69
 set_track mm/kasan/common.c:77 [inline]
 __kasan_kmalloc mm/kasan/common.c:510 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:483
 kmalloc include/linux/slab.h:556 [inline]
 kzalloc include/linux/slab.h:690 [inline]
 usbvision_alloc drivers/media/usb/usbvision/usbvision-video.c:1298 [inline]
 usbvision_probe.cold+0x5c5/0x1f1f drivers/media/usb/usbvision/usbvision-video.c:1452
 usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
 really_probe+0x281/0x6d0 drivers/base/dd.c:548
 driver_probe_device+0x104/0x210 drivers/base/dd.c:721
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430
 __device_attach+0x217/0x360 drivers/base/dd.c:894
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490
 device_add+0xae6/0x16f0 drivers/base/core.c:2202
 usb_set_configuration+0xdf6/0x1670 drivers/usb/core/message.c:2023
 generic_probe+0x9d/0xd5 drivers/usb/core/generic.c:210
 usb_probe_device+0x99/0x100 drivers/usb/core/driver.c:266
 really_probe+0x281/0x6d0 drivers/base/dd.c:548
 driver_probe_device+0x104/0x210 drivers/base/dd.c:721
 __device_attach_driver+0x1c2/0x220 drivers/base/dd.c:828
 bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:430
 __device_attach+0x217/0x360 drivers/base/dd.c:894
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:490
 device_add+0xae6/0x16f0 drivers/base/core.c:2202
 usb_new_device.cold+0x6a4/0xe79 drivers/usb/core/hub.c:2537
 hub_port_connect drivers/usb/core/hub.c:5184 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5324 [inline]
 port_event drivers/usb/core/hub.c:5470 [inline]
 hub_event+0x1df8/0x3800 drivers/usb/core/hub.c:5552
 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
 worker_thread+0x96/0xe20 kernel/workqueue.c:2415
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Freed by task 2135:
 save_stack+0x1b/0x80 mm/kasan/common.c:69
 set_track mm/kasan/common.c:77 [inline]
 kasan_set_free_info mm/kasan/common.c:332 [inline]
 __kasan_slab_free+0x130/0x180 mm/kasan/common.c:471
 slab_free_hook mm/slub.c:1424 [inline]
 slab_free_freelist_hook mm/slub.c:1475 [inline]
 slab_free mm/slub.c:3025 [inline]
 kfree+0xe4/0x320 mm/slub.c:3977
 usbvision_release+0x181/0x1c0 drivers/media/usb/usbvision/usbvision-video.c:1347
 usbvision_disconnect+0x16c/0x1d0 drivers/media/usb/usbvision/usbvision-video.c:1570
 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423
 __device_release_driver drivers/base/dd.c:1134 [inline]
 device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1165
 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:532
 device_del+0x420/0xb20 drivers/base/core.c:2376
 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237
 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2200
 hub_port_connect drivers/usb/core/hub.c:5035 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5324 [inline]
 port_event drivers/usb/core/hub.c:5470 [inline]
 hub_event+0x16f2/0x3800 drivers/usb/core/hub.c:5552
 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269
 process_scheduled_works kernel/workqueue.c:2331 [inline]
 worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
 kthread+0x318/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

The buggy address belongs to the object at ffff8881c8de0000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 7040 bytes inside of
 8192-byte region [ffff8881c8de0000, ffff8881c8de2000)
The buggy address belongs to the page:
page:ffffea0007237800 refcount:1 mapcount:0 mapping:ffff8881da00c500 index:0x0 compound_mapcount: 0
flags: 0x200000000010200(slab|head)
raw: 0200000000010200 ffffea0006bb4400 0000000200000002 ffff8881da00c500
raw: 0000000000000000 0000000080020002 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881c8de1a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881c8de1b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8881c8de1b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff8881c8de1c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881c8de1c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/11/28 15:48 https://github.com/google/kasan.git usb-fuzzer da06441bb485 97264cb1 .config console log report ci2-upstream-usb
2019/10/09 16:42 https://github.com/google/kasan.git usb-fuzzer 58d5f26a5584 312c6a5a .config console log report ci2-upstream-usb
2019/09/21 21:06 https://github.com/google/kasan.git usb-fuzzer e0bd8d794fc9 d96e88f3 .config console log report ci2-upstream-usb
2019/09/14 08:58 https://github.com/google/kasan.git usb-fuzzer f0df5c1be1e9 32d59357 .config console log report ci2-upstream-usb
2019/07/28 07:59 https://github.com/google/kasan.git usb-fuzzer 6a3599ceaa39 c85e1c5b .config console log report ci2-upstream-usb
* Struck through repros no longer work on HEAD.