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

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: fac04efc5c79 Linux 6.13-rc2
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16bdd944580000
kernel config: https://syzkaller.appspot.com/x/.config?x=1fe4854f351e948c
dashboard link: https://syzkaller.appspot.com/bug?extid=52184376977ebba5a92f
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/5b59ffa1ee4d/disk-fac04efc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2b25b47f9969/vmlinux-fac04efc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a7b8a70846c9/bzImage-fac04efc.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+521843...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in sg_new_write / sg_new_write

write to 0xffff8881182d3319 of 1 bytes by task 4280 on cpu 1:
sg_new_write+0x88/0x8e0 drivers/scsi/sg.c:722
sg_write+0x28e/0x710 drivers/scsi/sg.c:628
vfs_write+0x281/0x920 fs/read_write.c:677
ksys_write+0xe8/0x1b0 fs/read_write.c:731
__do_sys_write fs/read_write.c:742 [inline]
__se_sys_write fs/read_write.c:739 [inline]
__x64_sys_write+0x42/0x50 fs/read_write.c:739
x64_sys_call+0x287e/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:2
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

write to 0xffff8881182d3319 of 1 bytes by task 4279 on cpu 0:
sg_new_write+0x88/0x8e0 drivers/scsi/sg.c:722
sg_write+0x28e/0x710 drivers/scsi/sg.c:628
vfs_write+0x281/0x920 fs/read_write.c:677
ksys_write+0xe8/0x1b0 fs/read_write.c:731
__do_sys_write fs/read_write.c:742 [inline]
__se_sys_write fs/read_write.c:739 [inline]
__x64_sys_write+0x42/0x50 fs/read_write.c:739
x64_sys_call+0x287e/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:2
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: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4279 Comm: syz.4.264 Not tainted 6.13.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================


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