[moderation] [kernel?] KCSAN: data-race in dev_uevent / really_probe (6)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 41bccc98fb79 Linux 6.8-rc2
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15df8efde80000
kernel config: https://syzkaller.appspot.com/x/.config?x=243bc832fc3f4a47
dashboard link: https://syzkaller.appspot.com/bug?extid=ffa8143439596313a85a
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [gre...@linuxfoundation.org linux-...@vger.kernel.org raf...@kernel.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6ef13a3b8584/disk-41bccc98.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f2c2c944dae8/vmlinux-41bccc98.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d714989cf437/bzImage-41bccc98.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ffa814...@syzkaller.appspotmail.com

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

write to 0xffff888102ba48b8 of 8 bytes by task 12174 on cpu 1:
really_probe+0x9a/0x620 drivers/base/dd.c:632
__driver_probe_device+0x12d/0x200 drivers/base/dd.c:800
driver_probe_device+0x38/0x2f0 drivers/base/dd.c:830
__device_attach_driver+0x213/0x310 drivers/base/dd.c:958
bus_for_each_drv+0x1ca/0x240 drivers/base/bus.c:457
__device_attach+0x1c3/0x290 drivers/base/dd.c:1030
device_attach+0x17/0x20 drivers/base/dd.c:1073
proc_ioctl+0x332/0x3f0 drivers/usb/core/devio.c:2365
usbdev_ioctl+0x1f07/0x3e00 drivers/usb/core/devio.c:2824
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:871 [inline]
__se_sys_ioctl+0xcf/0x140 fs/ioctl.c:857
__x64_sys_ioctl+0x43/0x50 fs/ioctl.c:857
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x59/0x120 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

read to 0xffff888102ba48b8 of 8 bytes by task 3276 on cpu 0:
dev_uevent+0x235/0x360 drivers/base/core.c:2575
uevent_show+0x102/0x1e0 drivers/base/core.c:2647
dev_attr_show+0x39/0x90 drivers/base/core.c:2350
sysfs_kf_seq_show+0x179/0x240 fs/sysfs/file.c:59
kernfs_seq_show+0x78/0x90 fs/kernfs/file.c:205
seq_read_iter+0x2bc/0x8f0 fs/seq_file.c:230
kernfs_fop_read_iter+0xc8/0x2e0 fs/kernfs/file.c:279
call_read_iter include/linux/fs.h:2079 [inline]
new_sync_read fs/read_write.c:395 [inline]
vfs_read+0x5ab/0x6a0 fs/read_write.c:476
ksys_read+0xeb/0x1a0 fs/read_write.c:619
__do_sys_read fs/read_write.c:629 [inline]
__se_sys_read fs/read_write.c:627 [inline]
__x64_sys_read+0x42/0x50 fs/read_write.c:627
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x59/0x120 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000000000000000 -> 0xffffffff85eca5b0

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3276 Comm: udevd Not tainted 6.8.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
==================================================================


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