[moderation] [fs?] [mm?] KCSAN: data-race in read_pages / read_pages (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: bee0e7762ad2 Merge tag 'for-linus-iommufd' of git://git.ke..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1463718ce80000
kernel config: https://syzkaller.appspot.com/x/.config?x=ac34c1f29a8029df
dashboard link: https://syzkaller.appspot.com/bug?extid=be54111414b9daaa8cfa
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
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/233be5f65dd2/disk-bee0e776.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/94423738a289/vmlinux-bee0e776.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0b977463fa9a/bzImage-bee0e776.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+be5411...@syzkaller.appspotmail.com

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

read-write to 0xffff888151442b80 of 4 bytes by task 5502 on cpu 0:
read_pages+0x23c/0x530 mm/readahead.c:170
page_cache_ra_unbounded+0x2aa/0x2e0 mm/readahead.c:269
do_page_cache_ra mm/readahead.c:299 [inline]
page_cache_ra_order mm/readahead.c:546 [inline]
ondemand_readahead+0x524/0x690 mm/readahead.c:668
page_cache_async_ra+0x94/0xa0 mm/readahead.c:717
filemap_readahead mm/filemap.c:2472 [inline]
filemap_get_pages+0x397/0xf90 mm/filemap.c:2513
filemap_read+0x214/0x680 mm/filemap.c:2593
generic_file_read_iter+0x78/0x330 mm/filemap.c:2772
ext4_file_read_iter+0x1d8/0x2a0
call_read_iter include/linux/fs.h:2014 [inline]
copy_splice_read+0x26b/0x4b0 fs/splice.c:364
vfs_splice_read fs/splice.c:992 [inline]
splice_direct_to_actor+0x2aa/0x690 fs/splice.c:1069
do_splice_direct+0x10d/0x190 fs/splice.c:1194
do_sendfile+0x3c4/0x980 fs/read_write.c:1254
__do_sys_sendfile64 fs/read_write.c:1322 [inline]
__se_sys_sendfile64 fs/read_write.c:1308 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

read-write to 0xffff888151442b80 of 4 bytes by task 5517 on cpu 1:
read_pages+0x23c/0x530 mm/readahead.c:170
page_cache_ra_unbounded+0x2aa/0x2e0 mm/readahead.c:269
do_page_cache_ra mm/readahead.c:299 [inline]
page_cache_ra_order mm/readahead.c:546 [inline]
ondemand_readahead+0x524/0x690 mm/readahead.c:668
page_cache_async_ra+0x94/0xa0 mm/readahead.c:717
filemap_readahead mm/filemap.c:2472 [inline]
filemap_get_pages+0x397/0xf90 mm/filemap.c:2513
filemap_read+0x214/0x680 mm/filemap.c:2593
generic_file_read_iter+0x78/0x330 mm/filemap.c:2772
ext4_file_read_iter+0x1d8/0x2a0
call_read_iter include/linux/fs.h:2014 [inline]
copy_splice_read+0x26b/0x4b0 fs/splice.c:364
vfs_splice_read fs/splice.c:992 [inline]
splice_direct_to_actor+0x2aa/0x690 fs/splice.c:1069
do_splice_direct+0x10d/0x190 fs/splice.c:1194
do_sendfile+0x3c4/0x980 fs/read_write.c:1254
__do_sys_sendfile64 fs/read_write.c:1322 [inline]
__se_sys_sendfile64 fs/read_write.c:1308 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x00000009 -> 0x00000004

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 5517 Comm: syz-executor.3 Not tainted 6.7.0-rc4-syzkaller-00009-gbee0e7762ad2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================
==================================================================
BUG: KCSAN: data-race in read_pages / read_pages

read to 0xffff888151442b84 of 4 bytes by task 5502 on cpu 1:
read_pages+0x259/0x530 mm/readahead.c:171
page_cache_ra_unbounded+0x2aa/0x2e0 mm/readahead.c:269
do_page_cache_ra mm/readahead.c:299 [inline]
page_cache_ra_order mm/readahead.c:546 [inline]
ondemand_readahead+0x524/0x690 mm/readahead.c:668
page_cache_async_ra+0x94/0xa0 mm/readahead.c:717
filemap_readahead mm/filemap.c:2472 [inline]
filemap_get_pages+0x397/0xf90 mm/filemap.c:2513
filemap_read+0x214/0x680 mm/filemap.c:2593
generic_file_read_iter+0x78/0x330 mm/filemap.c:2772
ext4_file_read_iter+0x1d8/0x2a0
call_read_iter include/linux/fs.h:2014 [inline]
copy_splice_read+0x26b/0x4b0 fs/splice.c:364
vfs_splice_read fs/splice.c:992 [inline]
splice_direct_to_actor+0x2aa/0x690 fs/splice.c:1069
do_splice_direct+0x10d/0x190 fs/splice.c:1194
do_sendfile+0x3c4/0x980 fs/read_write.c:1254
__do_sys_sendfile64 fs/read_write.c:1322 [inline]
__se_sys_sendfile64 fs/read_write.c:1308 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

write to 0xffff888151442b84 of 4 bytes by task 5517 on cpu 0:
read_pages+0x284/0x530 mm/readahead.c:172
page_cache_ra_unbounded+0x2aa/0x2e0 mm/readahead.c:269
do_page_cache_ra mm/readahead.c:299 [inline]
page_cache_ra_order mm/readahead.c:546 [inline]
ondemand_readahead+0x524/0x690 mm/readahead.c:668
page_cache_async_ra+0x94/0xa0 mm/readahead.c:717
filemap_readahead mm/filemap.c:2472 [inline]
filemap_get_pages+0x397/0xf90 mm/filemap.c:2513
filemap_read+0x214/0x680 mm/filemap.c:2593
generic_file_read_iter+0x78/0x330 mm/filemap.c:2772
ext4_file_read_iter+0x1d8/0x2a0
call_read_iter include/linux/fs.h:2014 [inline]
copy_splice_read+0x26b/0x4b0 fs/splice.c:364
vfs_splice_read fs/splice.c:992 [inline]
splice_direct_to_actor+0x2aa/0x690 fs/splice.c:1069
do_splice_direct+0x10d/0x190 fs/splice.c:1194
do_sendfile+0x3c4/0x980 fs/read_write.c:1254
__do_sys_sendfile64 fs/read_write.c:1322 [inline]
__se_sys_sendfile64 fs/read_write.c:1308 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x00000010 -> 0x0000000f

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5517 Comm: syz-executor.3 Not tainted 6.7.0-rc4-syzkaller-00009-gbee0e7762ad2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================
==================================================================
BUG: KCSAN: data-race in ondemand_readahead / ondemand_readahead

read to 0xffff888151442b78 of 8 bytes by task 5502 on cpu 1:
ondemand_readahead+0x13a/0x690 mm/readahead.c:580
page_cache_sync_ra+0x27e/0x2a0 mm/readahead.c:695
page_cache_sync_readahead include/linux/pagemap.h:1283 [inline]
filemap_get_pages+0x251/0xf90 mm/filemap.c:2497
filemap_read+0x214/0x680 mm/filemap.c:2593
generic_file_read_iter+0x78/0x330 mm/filemap.c:2772
ext4_file_read_iter+0x1d8/0x2a0
call_read_iter include/linux/fs.h:2014 [inline]
copy_splice_read+0x26b/0x4b0 fs/splice.c:364
vfs_splice_read fs/splice.c:992 [inline]
splice_direct_to_actor+0x2aa/0x690 fs/splice.c:1069
do_splice_direct+0x10d/0x190 fs/splice.c:1194
do_sendfile+0x3c4/0x980 fs/read_write.c:1254
__do_sys_sendfile64 fs/read_write.c:1322 [inline]
__se_sys_sendfile64 fs/read_write.c:1308 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

write to 0xffff888151442b78 of 8 bytes by task 5517 on cpu 0:
try_context_readahead mm/readahead.c:457 [inline]
ondemand_readahead+0x633/0x690 mm/readahead.c:633
page_cache_sync_ra+0x27e/0x2a0 mm/readahead.c:695
page_cache_sync_readahead include/linux/pagemap.h:1283 [inline]
filemap_get_pages+0x251/0xf90 mm/filemap.c:2497
filemap_read+0x214/0x680 mm/filemap.c:2593
generic_file_read_iter+0x78/0x330 mm/filemap.c:2772
ext4_file_read_iter+0x1d8/0x2a0
call_read_iter include/linux/fs.h:2014 [inline]
copy_splice_read+0x26b/0x4b0 fs/splice.c:364
vfs_splice_read fs/splice.c:992 [inline]
splice_direct_to_actor+0x2aa/0x690 fs/splice.c:1069
do_splice_direct+0x10d/0x190 fs/splice.c:1194
do_sendfile+0x3c4/0x980 fs/read_write.c:1254
__do_sys_sendfile64 fs/read_write.c:1322 [inline]
__se_sys_sendfile64 fs/read_write.c:1308 [inline]
__x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1308
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

value changed: 0x0000000000000a01 -> 0x0000000000000a02

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5517 Comm: syz-executor.3 Not tainted 6.7.0-rc4-syzkaller-00009-gbee0e7762ad2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.