Hello,
syzbot has tested the proposed patch but the reproducer still triggered
crash:
KASAN: use-after-free Read in usb_driver_release_interface
usb 1-1: Loading firmware file isl3887usb
usb 1-1: Direct firmware load for isl3887usb failed with error -2
usb 1-1: Firmware not found.
p54usb 1-1:0.143: failed to initialize device (-2)
==================================================================
BUG: KASAN: use-after-free in usb_driver_release_interface+0x16b/0x190
drivers/usb/core/driver.c:584
Read of size 8 at addr ffff88808fc31218 by task kworker/0:1/12
CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.1.0-rc3-g43151d6-dirty #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: events request_firmware_work_func
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
usb_driver_release_interface+0x16b/0x190 drivers/usb/core/driver.c:584
p54u_load_firmware_cb+0x390/0x420
drivers/net/wireless/intersil/p54/p54usb.c:948
request_firmware_work_func+0x12d/0x249
drivers/base/firmware_loader/main.c:785
process_one_work+0x90f/0x1580 kernel/workqueue.c:2269
worker_thread+0x9b/0xe20 kernel/workqueue.c:2415
kthread+0x313/0x420 kernel/kthread.c:253
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Allocated by task 12:
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
kmalloc include/linux/slab.h:547 [inline]
kzalloc include/linux/slab.h:742 [inline]
usb_set_configuration+0x2e0/0x1740 drivers/usb/core/message.c:1846
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
worker_thread+0x9b/0xe20 kernel/workqueue.c:2415
kthread+0x313/0x420 kernel/kthread.c:253
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Freed by task 5394:
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
device_release+0x7d/0x210 drivers/base/core.c:1064
kobject_cleanup lib/kobject.c:662 [inline]
kobject_release lib/kobject.c:691 [inline]
kref_put include/linux/kref.h:67 [inline]
kobject_put+0x1df/0x4f0 lib/kobject.c:708
put_device+0x21/0x30 drivers/base/core.c:2205
usb_disable_device+0x309/0x790 drivers/usb/core/message.c:1244
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
worker_thread+0x9b/0xe20 kernel/workqueue.c:2415
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 ffff88808fc31100
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 280 bytes inside of
2048-byte region [ffff88808fc31100, ffff88808fc31900)
The buggy address belongs to the page:
page:ffffea00023f0c00 count:1 mapcount:0 mapping:ffff88812c3f4800 index:0x0
compound_mapcount: 0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 dead000000000100 dead000000000200 ffff88812c3f4800
raw: 0000000000000000 00000000000f000f 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff88808fc31100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88808fc31180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88808fc31200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88808fc31280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88808fc31300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Tested on:
commit: 43151d6c 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=148b9428a00000
kernel config: https://syzkaller.appspot.com/x/.config?x=4183eeef650d1234
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
patch: https://syzkaller.appspot.com/x/patch.diff?x=17642018a00000
