Hello,
syzbot found the following crash on:
HEAD commit: 9939f56e usb-fuzzer: main usb gadget fuzzer driver
git tree: https://github.com/google/kasan.git usb-fuzzer
console output: https://syzkaller.appspot.com/x/log.txt?x=12e0f72da00000
kernel config: https://syzkaller.appspot.com/x/.config?x=df134eda130bb43a
dashboard link: https://syzkaller.appspot.com/bug?extid=79d18aac4bf1770dd050
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
Unfortunately, I don't have any reproducer for this crash yet.
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+79d18aac4bf1770dd050@xxxxxxxxxxxxxxxxxxxxxxxxx
usb 2-1: config 0 descriptor??
==================================================================
BUG: KASAN: slab-out-of-bounds in string_nocheck+0x1d2/0x200
lib/vsprintf.c:605
Read of size 1 at addr ffff8881cda45b20 by task kworker/0:0/5
CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.2.0-rc5+ #11
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xca/0x13e lib/dump_stack.c:113
print_address_description+0x67/0x231 mm/kasan/report.c:188
__kasan_report.cold+0x1a/0x32 mm/kasan/report.c:317
kasan_report+0xe/0x20 mm/kasan/common.c:614
string_nocheck+0x1d2/0x200 lib/vsprintf.c:605
string+0xe5/0xf0 lib/vsprintf.c:668
vsnprintf+0x7d3/0x14f0 lib/vsprintf.c:2503
vscnprintf+0x29/0x80 lib/vsprintf.c:2606
vprintk_store+0x40/0x4b0 kernel/printk/printk.c:1907
vprintk_emit+0xc8/0x3e0 kernel/printk/printk.c:1968
vprintk_func+0x75/0x113 kernel/printk/printk_safe.c:386
printk+0xba/0xed kernel/printk/printk.c:2046
device_authorization drivers/media/usb/hdpvr/hdpvr-core.c:140 [inline]
hdpvr_device_init drivers/media/usb/hdpvr/hdpvr-core.c:201 [inline]
hdpvr_probe.cold+0x194/0x1247 drivers/media/usb/hdpvr/hdpvr-core.c:342
usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
really_probe+0x281/0x660 drivers/base/dd.c:509
driver_probe_device+0x104/0x210 drivers/base/dd.c:670
__device_attach_driver+0x1c2/0x220 drivers/base/dd.c:777
bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
__device_attach+0x217/0x360 drivers/base/dd.c:843
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
device_add+0xae6/0x16f0 drivers/base/core.c:2111
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+0x281/0x660 drivers/base/dd.c:509
driver_probe_device+0x104/0x210 drivers/base/dd.c:670
__device_attach_driver+0x1c2/0x220 drivers/base/dd.c:777
bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
__device_attach+0x217/0x360 drivers/base/dd.c:843
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
device_add+0xae6/0x16f0 drivers/base/core.c:2111
usb_new_device.cold+0x8c1/0x1016 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+0x1ada/0x3590 drivers/usb/core/hub.c:5432
process_one_work+0x905/0x1570 kernel/workqueue.c:2269
process_scheduled_works kernel/workqueue.c:2331 [inline]
worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
kthread+0x30b/0x410 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Allocated by task 5:
save_stack+0x1b/0x80 mm/kasan/common.c:71
set_track mm/kasan/common.c:79 [inline]
__kasan_kmalloc mm/kasan/common.c:489 [inline]
__kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:462
kmalloc include/linux/slab.h:547 [inline]
hdpvr_probe+0x1ce/0xac0 drivers/media/usb/hdpvr/hdpvr-core.c:297
usb_probe_interface+0x305/0x7a0 drivers/usb/core/driver.c:361
really_probe+0x281/0x660 drivers/base/dd.c:509
driver_probe_device+0x104/0x210 drivers/base/dd.c:670
__device_attach_driver+0x1c2/0x220 drivers/base/dd.c:777
bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
__device_attach+0x217/0x360 drivers/base/dd.c:843
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
device_add+0xae6/0x16f0 drivers/base/core.c:2111
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+0x281/0x660 drivers/base/dd.c:509
driver_probe_device+0x104/0x210 drivers/base/dd.c:670
__device_attach_driver+0x1c2/0x220 drivers/base/dd.c:777
bus_for_each_drv+0x15c/0x1e0 drivers/base/bus.c:454
__device_attach+0x217/0x360 drivers/base/dd.c:843
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:514
device_add+0xae6/0x16f0 drivers/base/core.c:2111
usb_new_device.cold+0x8c1/0x1016 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+0x1ada/0x3590 drivers/usb/core/hub.c:5432
process_one_work+0x905/0x1570 kernel/workqueue.c:2269
process_scheduled_works kernel/workqueue.c:2331 [inline]
worker_thread+0x7ab/0xe20 kernel/workqueue.c:2417
kthread+0x30b/0x410 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Freed by task 0:
(stack is not available)
The buggy address belongs to the object at ffff8881cda45ae0
which belongs to the cache kmalloc-64 of size 64
The buggy address is located 0 bytes to the right of
64-byte region [ffff8881cda45ae0, ffff8881cda45b20)
The buggy address belongs to the page:
page:ffffea0007369140 refcount:1 mapcount:0 mapping:ffff8881dac03600
index:0x0
flags: 0x200000000000200(slab)
raw: 0200000000000200 dead000000000100 dead000000000200 ffff8881dac03600
raw: 0000000000000000 00000000802a002a 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8881cda45a00: fc fc fc fc fb fb fb fb fb fb fb fb fc fc fc fc
ffff8881cda45a80: fb fb fb fb fb fb fb fb fc fc fc fc 00 00 00 00
ffff8881cda45b00: 00 00 00 00 fc fc fc fc fb fb fb fb fb fb fb fb
^
ffff8881cda45b80: fc fc fc fc 00 00 00 00 00 00 00 00 fc fc fc fc
ffff8881cda45c00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
==================================================================
---
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