Hello,
syzbot found the following crash on:
HEAD commit: 22be26f7 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=17bf83e8e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=387eccb7ac68ec5
dashboard link: https://syzkaller.appspot.com/bug?extid=11eed0a63c4f31acd096
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+11eed0a63c4f31acd096@xxxxxxxxxxxxxxxxxxxxxxxxx
==================================================================
BUG: KASAN: slab-out-of-bounds in read_descriptors+0x256/0x270
drivers/usb/core/sysfs.c:903
Read of size 8 at addr ffff8881ce6e4350 by task udevd/9454
CPU: 1 PID: 9454 Comm: udevd Not tainted 5.4.0-rc3+ #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
read_descriptors+0x256/0x270 drivers/usb/core/sysfs.c:903
sysfs_kf_bin_read+0x196/0x270 fs/sysfs/file.c:99
kernfs_file_direct_read fs/kernfs/file.c:213 [inline]
kernfs_fop_read+0x2eb/0x560 fs/kernfs/file.c:253
__vfs_read+0x76/0x100 fs/read_write.c:425
vfs_read+0x1ea/0x430 fs/read_write.c:461
ksys_read+0x127/0x250 fs/read_write.c:587
do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f10f2702310
Code: 73 01 c3 48 8b 0d 28 4b 2b 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb
ea 90 90 83 3d e5 a2 2b 00 00 75 10 b8 00 00 00 00 0f 05 <48> 3d 01 f0 ff
ff 73 31 c3 48 83 ec 08 e8 6e 8a 01 00 48 89 04 24
RSP: 002b:00007ffd6a810e48 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007f10f2702310
RDX: 0000000000010011 RSI: 00007ffd6a810e80 RDI: 0000000000000005
RBP: 000000000174e640 R08: 000000000000000c R09: 75642f6d726f6674
R10: 2e6463685f796d6d R11: 0000000000000246 R12: 00007ffd6a821590
R13: 0000000001741250 R14: 0000000000000000 R15: 00000000017421c0
Allocated by task 22:
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:561 [inline]
kzalloc include/linux/slab.h:690 [inline]
usb_get_configuration+0x184/0x3050 drivers/usb/core/config.c:825
usb_enumerate_device drivers/usb/core/hub.c:2369 [inline]
usb_new_device+0xd3/0x160 drivers/usb/core/hub.c:2505
hub_port_connect drivers/usb/core/hub.c:5183 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5323 [inline]
port_event drivers/usb/core/hub.c:5469 [inline]
hub_event+0x1dd0/0x37e0 drivers/usb/core/hub.c:5551
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 2807:
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:3018 [inline]
kfree+0xe4/0x320 mm/slub.c:3967
usb_set_configuration+0xba8/0x1670 drivers/usb/core/message.c:1962
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:2201
usb_new_device.cold+0x6a4/0xe79 drivers/usb/core/hub.c:2536
hub_port_connect drivers/usb/core/hub.c:5183 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5323 [inline]
port_event drivers/usb/core/hub.c:5469 [inline]
hub_event+0x1dd0/0x37e0 drivers/usb/core/hub.c:5551
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
The buggy address belongs to the object at ffff8881ce6e4348
which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes to the right of
8-byte region [ffff8881ce6e4348, ffff8881ce6e4350)
The buggy address belongs to the page:
page:ffffea000739b900 refcount:1 mapcount:0 mapping:ffff8881da003900
index:0x0
flags: 0x200000000000200(slab)
raw: 0200000000000200 ffffea0007632e40 0000000a0000000a ffff8881da003900
raw: 0000000000000000 0000000000aa00aa 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8881ce6e4200: fc fc fb fc fc fb fc fc fb fc fc fb fc fc fb fc
ffff8881ce6e4280: fc fb fc fc fb fc fc fb fc fc fb fc fc fb fc fc
ffff8881ce6e4300: fb fc fc fb fc fc fb fc fc 00 fc fc fb fc fc fb
^
ffff8881ce6e4380: fc fc fb fc fc fb fc fc fb fc fc fb fc fc fb fc
ffff8881ce6e4400: fc fb fc fc fb fc fc fb fc fc fb fc fc fb fc fc
==================================================================
---
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