[moderation] [mm?] KCSAN: data-race in _copy_from_iter / _copy_from_iter (5)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4e82c87058f4 Merge tag 'rust-6.15' of git://git.kernel.org..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16c02404580000
kernel config: https://syzkaller.appspot.com/x/.config?x=bdb65086dcaf0454
dashboard link: https://syzkaller.appspot.com/bug?extid=b598ec189233b099946c
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
CC: [ak...@linux-foundation.org linux-...@vger.kernel.org linu...@kvack.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e2e48760d09b/disk-4e82c870.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/14aa196a7657/vmlinux-4e82c870.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6f0f1baf84d2/bzImage-4e82c870.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+b598ec...@syzkaller.appspotmail.com

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

write to 0xffff888130863000 of 4096 bytes by task 2235 on cpu 1:
instrument_copy_from_user_before include/linux/instrumented.h:130 [inline]
copy_from_user_iter lib/iov_iter.c:54 [inline]
iterate_ubuf include/linux/iov_iter.h:30 [inline]
iterate_and_advance2 include/linux/iov_iter.h:300 [inline]
iterate_and_advance include/linux/iov_iter.h:328 [inline]
__copy_from_iter lib/iov_iter.c:249 [inline]
_copy_from_iter+0x136/0xd10 lib/iov_iter.c:260
copy_page_from_iter+0x14f/0x280 lib/iov_iter.c:422
process_vm_rw_pages mm/process_vm_access.c:43 [inline]
process_vm_rw_single_vec mm/process_vm_access.c:118 [inline]
process_vm_rw_core mm/process_vm_access.c:216 [inline]
process_vm_rw+0x5a2/0x8a0 mm/process_vm_access.c:284
__do_sys_process_vm_writev mm/process_vm_access.c:304 [inline]
__se_sys_process_vm_writev mm/process_vm_access.c:299 [inline]
__x64_sys_process_vm_writev+0x7a/0x90 mm/process_vm_access.c:299
x64_sys_call+0xaf3/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:312
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff888130863000 of 4096 bytes by task 2234 on cpu 0:
instrument_copy_from_user_before include/linux/instrumented.h:130 [inline]
copy_from_user_iter lib/iov_iter.c:54 [inline]
iterate_ubuf include/linux/iov_iter.h:30 [inline]
iterate_and_advance2 include/linux/iov_iter.h:300 [inline]
iterate_and_advance include/linux/iov_iter.h:328 [inline]
__copy_from_iter lib/iov_iter.c:249 [inline]
_copy_from_iter+0x136/0xd10 lib/iov_iter.c:260
copy_page_from_iter+0x14f/0x280 lib/iov_iter.c:422
process_vm_rw_pages mm/process_vm_access.c:43 [inline]
process_vm_rw_single_vec mm/process_vm_access.c:118 [inline]
process_vm_rw_core mm/process_vm_access.c:216 [inline]
process_vm_rw+0x5a2/0x8a0 mm/process_vm_access.c:284
__do_sys_process_vm_writev mm/process_vm_access.c:304 [inline]
__se_sys_process_vm_writev mm/process_vm_access.c:299 [inline]
__x64_sys_process_vm_writev+0x7a/0x90 mm/process_vm_access.c:299
x64_sys_call+0xaf3/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:312
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 2234 Comm: syz.2.22466 Not tainted 6.14.0-syzkaller-10892-g4e82c87058f4 #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
==================================================================
netdevsim netdevsim2 netdevsim0: Unsupported IPsec algorithm
netlink: 8 bytes leftover after parsing attributes in process `syz.2.22466'.
platform regulatory.0: Direct firmware load for regulatory.db failed with error -2


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