[moderation] [fs?] [mm?] KCSAN: data-race in __filemap_add_folio / invalidate_bdev (11)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: d295082ea672 Merge tag 'spdx-7.0-rc1' of git://git.kernel...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10916722580000
kernel config: https://syzkaller.appspot.com/x/.config?x=4c7a3cd4d19e835b
dashboard link: https://syzkaller.appspot.com/bug?extid=7ebe8796457c16621407
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
CC: [ak...@linux-foundation.org linux-...@vger.kernel.org linux-...@vger.kernel.org linu...@kvack.org wi...@infradead.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/98356c916efc/disk-d295082e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1bb89f4fd97a/vmlinux-d295082e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/87d64254210a/bzImage-d295082e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+7ebe87...@syzkaller.appspotmail.com

loop8: detected capacity change from 0 to 1024
EXT4-fs: inline encryption not supported
==================================================================
BUG: KCSAN: data-race in __filemap_add_folio / invalidate_bdev

read-write to 0xffff8881004891f8 of 8 bytes by task 11157 on cpu 1:
__filemap_add_folio+0x671/0x8b0 mm/filemap.c:919
filemap_add_folio+0x1d3/0x350 mm/filemap.c:966
page_cache_ra_unbounded+0x20e/0x450 mm/readahead.c:282
do_page_cache_ra mm/readahead.c:334 [inline]
force_page_cache_ra+0x18d/0x1d0 mm/readahead.c:364
page_cache_sync_ra+0x110/0x560 mm/readahead.c:582
filemap_get_pages+0x30a/0x1280 mm/filemap.c:2690
filemap_read+0x231/0xa10 mm/filemap.c:2800
blkdev_read_iter+0x22d/0x2e0 block/fops.c:856
new_sync_read fs/read_write.c:493 [inline]
vfs_read+0x6c0/0x7f0 fs/read_write.c:574
ksys_read+0xdc/0x1a0 fs/read_write.c:717
__do_sys_read fs/read_write.c:726 [inline]
__se_sys_read fs/read_write.c:724 [inline]
__x64_sys_read+0x40/0x50 fs/read_write.c:724
x64_sys_call+0x2886/0x3020 arch/x86/include/generated/asm/syscalls_64.h:1
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881004891f8 of 8 bytes by task 18080 on cpu 0:
invalidate_bdev+0x25/0x70 block/bdev.c:99
__ext4_fill_super fs/ext4/super.c:5768 [inline]
ext4_fill_super+0x2cf6/0x37c0 fs/ext4/super.c:5793
get_tree_bdev_flags+0x291/0x300 fs/super.c:1694
get_tree_bdev+0x1f/0x30 fs/super.c:1717
ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5825
vfs_get_tree+0x57/0x1d0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3760 [inline]
do_new_mount+0x288/0x8d0 fs/namespace.c:3836
path_mount+0x4d0/0xbc0 fs/namespace.c:4146
do_mount fs/namespace.c:4159 [inline]
__do_sys_mount fs/namespace.c:4348 [inline]
__se_sys_mount+0x28c/0x2e0 fs/namespace.c:4325
__x64_sys_mount+0x67/0x80 fs/namespace.c:4325
x64_sys_call+0x2d61/0x3020 arch/x86/include/generated/asm/syscalls_64.h:166
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000003 -> 0x0000000000000004

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 18080 Comm: syz.8.2548 Tainted: G W syzkaller #0 PREEMPT(full)
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
==================================================================


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