KCSAN: data-race in dev_uevent / usb_gadget_unregister_driver (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4ef8451b Merge tag 'perf-tools-for-v5.10-2020-11-03' of gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1542d43a500000
kernel config: https://syzkaller.appspot.com/x/.config?x=76dfc991796328d4
dashboard link: https://syzkaller.appspot.com/bug?extid=713848f2345b18220dbd
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project.git 913f6005669cfb590c99865a90bc51ed0983d09d)
CC: [ba...@kernel.org gre...@linuxfoundation.org lee....@linaro.org linux-...@vger.kernel.org linu...@vger.kernel.org peter...@nxp.com st...@rowland.harvard.edu]

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+713848...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in dev_uevent / usb_gadget_unregister_driver

write to 0xffff888102563078 of 8 bytes by task 11932 on cpu 1:
usb_gadget_remove_driver drivers/usb/gadget/udc/core.c:1346 [inline]
usb_gadget_unregister_driver+0x254/0x430 drivers/usb/gadget/udc/core.c:1493
raw_release+0xac/0x130 drivers/usb/gadget/legacy/raw_gadget.c:400
__fput+0x243/0x4d0 fs/file_table.c:281
____fput+0x11/0x20 fs/file_table.c:314
task_work_run+0x8e/0x110 kernel/task_work.c:151
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_user_mode_loop kernel/entry/common.c:164 [inline]
exit_to_user_mode_prepare+0x13c/0x170 kernel/entry/common.c:191
syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:266
do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888102563078 of 8 bytes by task 11988 on cpu 0:
dev_uevent+0x213/0x350 drivers/base/core.c:1899
uevent_show+0x10e/0x1f0 drivers/base/core.c:1971
dev_attr_show+0x35/0x90 drivers/base/core.c:1673
sysfs_kf_seq_show+0x152/0x270 fs/sysfs/file.c:61
kernfs_seq_show+0x74/0x80 fs/kernfs/file.c:167
seq_read+0x2de/0x890 fs/seq_file.c:208
kernfs_fop_read+0xce/0x2f0 fs/kernfs/file.c:251
vfs_read+0x154/0x5c0 fs/read_write.c:494
ksys_read+0xce/0x180 fs/read_write.c:634
__do_sys_read fs/read_write.c:644 [inline]
__se_sys_read fs/read_write.c:642 [inline]
__x64_sys_read+0x3e/0x50 fs/read_write.c:642
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 11988 Comm: systemd-udevd Not tainted 5.10.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.