Hello,
syzbot has tested the proposed patch but the reproducer still triggered crash:
KASAN: use-after-free Read in hfa384x_usbin_callback
==================================================================
BUG: KASAN: use-after-free in memcpy include/linux/string.h:381 [inline]
BUG: KASAN: use-after-free in skb_put_data include/linux/skbuff.h:2284 [inline]
BUG: KASAN: use-after-free in hfa384x_int_rxmonitor drivers/staging/wlan-ng/hfa384x_usb.c:3412 [inline]
BUG: KASAN: use-after-free in hfa384x_usbin_rx drivers/staging/wlan-ng/hfa384x_usb.c:3312 [inline]
BUG: KASAN: use-after-free in hfa384x_usbin_callback+0x1993/0x2360 drivers/staging/wlan-ng/hfa384x_usb.c:3026
Read of size 19671 at addr ffff8881cda7b33c by task kworker/1:2/95
CPU: 1 PID: 95 Comm: kworker/1:2 Not tainted 5.6.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xef/0x16e lib/dump_stack.c:118
print_address_description.constprop.0.cold+0xd3/0x314 mm/kasan/report.c:374
__kasan_report.cold+0x37/0x77 mm/kasan/report.c:506
kasan_report+0xe/0x20 mm/kasan/common.c:641
check_memory_region_inline mm/kasan/generic.c:185 [inline]
check_memory_region+0x152/0x1c0 mm/kasan/generic.c:192
memcpy+0x20/0x50 mm/kasan/common.c:127
memcpy include/linux/string.h:381 [inline]
skb_put_data include/linux/skbuff.h:2284 [inline]
hfa384x_int_rxmonitor drivers/staging/wlan-ng/hfa384x_usb.c:3412 [inline]
hfa384x_usbin_rx drivers/staging/wlan-ng/hfa384x_usb.c:3312 [inline]
hfa384x_usbin_callback+0x1993/0x2360 drivers/staging/wlan-ng/hfa384x_usb.c:3026
__usb_hcd_giveback_urb+0x29a/0x550 drivers/usb/core/hcd.c:1650
usb_hcd_giveback_urb+0x368/0x420 drivers/usb/core/hcd.c:1716
dummy_timer+0x1258/0x32ae drivers/usb/gadget/udc/dummy_hcd.c:1966
call_timer_fn+0x195/0x6f0 kernel/time/timer.c:1404
expire_timers kernel/time/timer.c:1449 [inline]
__run_timers kernel/time/timer.c:1773 [inline]
__run_timers kernel/time/timer.c:1740 [inline]
run_timer_softirq+0x5f9/0x1500 kernel/time/timer.c:1786
__do_softirq+0x21e/0x950 kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x178/0x1a0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:546 [inline]
smp_apic_timer_interrupt+0x141/0x540 arch/x86/kernel/apic/apic.c:1146
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
</IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/irqflags.h:85 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x3b/0x40 kernel/locking/spinlock.c:191
Code: e8 2a e8 96 fb 48 89 ef e8 f2 c9 97 fb f6 c7 02 75 11 53 9d e8 16 50 b5 fb 65 ff 0d f7 bd 72 7a 5b 5d c3 e8 07 4e b5 fb 53 9d <eb> ed 0f 1f 00 55 48 89 fd 65 ff 05 dd bd 72 7a 45 31 c9 41 b8 01
RSP: 0018:ffff8881d56b6f40 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000007 RBX: 0000000000000293 RCX: 0000000000000006
RDX: 0000000000000000 RSI: ffff8881d56a88f0 RDI: ffff8881d56a884c
RBP: ffff8881c0c64b80 R08: ffff8881d56a8000 R09: fffffbfff1266e8f
R10: fffffbfff1266e8e R11: ffffffff89337477 R12: 0000000000000000
R13: ffff8881c0c64bb8 R14: ffff8881c0c64b80 R15: ffff8881c0c64bb8
hfa384x_usbctlx_submit+0x1cb/0x260 drivers/staging/wlan-ng/hfa384x_usb.c:3834
hfa384x_docmd drivers/staging/wlan-ng/hfa384x_usb.c:1233 [inline]
hfa384x_cmd_initialize+0x290/0x4f0 drivers/staging/wlan-ng/hfa384x_usb.c:846
hfa384x_drvr_start+0x1f1/0x480 drivers/staging/wlan-ng/hfa384x_usb.c:2380
prism2sta_ifstate+0x24e/0x510 drivers/staging/wlan-ng/prism2sta.c:471
prism2sta_probe_usb.cold+0x1c8/0x49e drivers/staging/wlan-ng/prism2usb.c:112
usb_probe_interface+0x310/0x800 drivers/usb/core/driver.c:374
really_probe+0x290/0xac0 drivers/base/dd.c:551
driver_probe_device+0x223/0x350 drivers/base/dd.c:724
__device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831
bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431
__device_attach+0x217/0x390 drivers/base/dd.c:897
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491
device_add+0x1459/0x1bf0 drivers/base/core.c:2500
usb_set_configuration+0xe47/0x17d0 drivers/usb/core/message.c:2023
usb_generic_driver_probe+0x9d/0xe0 drivers/usb/core/generic.c:241
usb_probe_device+0xd9/0x230 drivers/usb/core/driver.c:272
really_probe+0x290/0xac0 drivers/base/dd.c:551
driver_probe_device+0x223/0x350 drivers/base/dd.c:724
__device_attach_driver+0x1d1/0x290 drivers/base/dd.c:831
bus_for_each_drv+0x162/0x1e0 drivers/base/bus.c:431
__device_attach+0x217/0x390 drivers/base/dd.c:897
bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491
device_add+0x1459/0x1bf0 drivers/base/core.c:2500
usb_new_device.cold+0x540/0xcd0 drivers/usb/core/hub.c:2548
hub_port_connect drivers/usb/core/hub.c:5195 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5335 [inline]
port_event drivers/usb/core/hub.c:5481 [inline]
hub_event+0x21cb/0x4300 drivers/usb/core/hub.c:5563
process_one_work+0x94b/0x1620 kernel/workqueue.c:2264
worker_thread+0x96/0xe20 kernel/workqueue.c:2410
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 page:
page:ffffea0007369e00 refcount:32737 mapcount:0 mapping:0000000000000000 index:0x0 compound_mapcount: 0
flags: 0x200000000010000(head)
raw: 0200000000010000 dead000000000100 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00007fe1ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8881cda7ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff8881cda7ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881cda80000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8881cda80080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8881cda80100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Tested on:
commit: e17994d1 usb: core: kcov: collect coverage from usb comple..
git tree: https://github.com/google/kasan.git
console output: https://syzkaller.appspot.com/x/log.txt?x=139ea05be00000
kernel config: https://syzkaller.appspot.com/x/.config?x=5d64370c438bc60
dashboard link: https://syzkaller.appspot.com/bug?extid=7d42d68643a35f71ac8a
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
patch: https://syzkaller.appspot.com/x/patch.diff?x=16d52b19e00000
