[moderation] [scsi?] KCSAN: data-race in sg_common_write / sg_finish_rem_req (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 35bb670d65fc Merge tag 'scsi-fixes' of git://git.kernel.or..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12611201980000
kernel config: https://syzkaller.appspot.com/x/.config?x=704451bc2941bcb0
dashboard link: https://syzkaller.appspot.com/bug?extid=c1c2a596fa01d826a550
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [James.B...@HansenPartnership.com dgil...@interlog.com linux-...@vger.kernel.org linux...@vger.kernel.org martin....@oracle.com]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/6e9f5b0b138d/disk-35bb670d.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8c5676b7d283/vmlinux-35bb670d.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8930e6840cb1/bzImage-35bb670d.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c1c2a5...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in sg_common_write / sg_finish_rem_req

write to 0xffff8881188c531d of 1 bytes by task 28922 on cpu 1:
sg_unlink_reserve drivers/scsi/sg.c:2069 [inline]
sg_finish_rem_req+0x117/0x270 drivers/scsi/sg.c:1851
sg_rq_end_io_usercontext+0x36/0x1c0 drivers/scsi/sg.c:1309
process_one_work kernel/workqueue.c:3231 [inline]
process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3312
worker_thread+0x526/0x730 kernel/workqueue.c:3393
kthread+0x1d1/0x210 kernel/kthread.c:389
ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffff8881188c531d of 1 bytes by task 10612 on cpu 0:
sg_start_req drivers/scsi/sg.c:1791 [inline]
sg_common_write+0x66a/0x8e0 drivers/scsi/sg.c:806
sg_new_write+0x82b/0x8e0 drivers/scsi/sg.c:773
sg_ioctl_common drivers/scsi/sg.c:938 [inline]
sg_ioctl+0xe28/0x1870 drivers/scsi/sg.c:1163
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl+0xd3/0x150 fs/ioctl.c:893
__x64_sys_ioctl+0x43/0x50 fs/ioctl.c:893
x64_sys_call+0x1581/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:17
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x01 -> 0x00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10612 Comm: syz-executor.1 Tainted: G W 6.10.0-rc4-syzkaller-00217-g35bb670d65fc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
==================================================================


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