Hello,
syzbot found the following issue on:
HEAD commit: 614da38e2f7a Merge tag 'hid-for-linus-2024051401' of git:/..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12d26ada980000
kernel config: https://syzkaller.appspot.com/x/.config?x=f5d2cbf33633f507
dashboard link: https://syzkaller.appspot.com/bug?extid=206133fb2e7b32bba4be
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/89eafb874b71/disk-614da38e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/356000512ad9/vmlinux-614da38e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/839c73939115/bzImage-614da38e.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]
=====================================================
BUG: KMSAN: uninit-value in crc32_body lib/crc32.c:110 [inline]
BUG: KMSAN: uninit-value in crc32_le_generic lib/crc32.c:179 [inline]
BUG: KMSAN: uninit-value in crc32_le_base+0x43c/0xd80 lib/crc32.c:197
crc32_body lib/crc32.c:110 [inline]
crc32_le_generic lib/crc32.c:179 [inline]
crc32_le_base+0x43c/0xd80 lib/crc32.c:197
nilfs_segbuf_fill_in_data_crc fs/nilfs2/segbuf.c:224 [inline]
nilfs_add_checksums_on_logs+0xb80/0xe40 fs/nilfs2/segbuf.c:327
nilfs_segctor_do_construct+0x9876/0xdeb0 fs/nilfs2/segment.c:2078
nilfs_segctor_construct+0x1eb/0xe30 fs/nilfs2/segment.c:2381
nilfs_segctor_thread_construct fs/nilfs2/segment.c:2489 [inline]
nilfs_segctor_thread+0xc50/0x11e0 fs/nilfs2/segment.c:2573
kthread+0x3e2/0x540 kernel/kthread.c:389
ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Uninit was stored to memory at:
memcpy_from_iter lib/iov_iter.c:73 [inline]
iterate_bvec include/linux/iov_iter.h:122 [inline]
iterate_and_advance2 include/linux/iov_iter.h:249 [inline]
iterate_and_advance include/linux/iov_iter.h:271 [inline]
__copy_from_iter lib/iov_iter.c:249 [inline]
copy_page_from_iter_atomic+0x12b7/0x2ae0 lib/iov_iter.c:481
generic_perform_write+0x4c1/0xc60 mm/filemap.c:3982
__generic_file_write_iter+0x20a/0x460 mm/filemap.c:4069
generic_file_write_iter+0x103/0x5b0 mm/filemap.c:4095
__kernel_write_iter+0x64d/0xc80 fs/read_write.c:523
dump_emit_page fs/coredump.c:895 [inline]
dump_user_range+0x8dc/0xee0 fs/coredump.c:956
elf_core_dump+0x57c7/0x5ae0 fs/binfmt_elf.c:2083
do_coredump+0x32d5/0x4920 fs/coredump.c:769
get_signal+0x267e/0x2d00 kernel/signal.c:2896
arch_do_signal_or_restart+0x53/0xcb0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x5d/0x160 kernel/entry/common.c:218
do_syscall_64+0xdc/0x1e0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Uninit was created at:
__alloc_pages+0x9d6/0xe70 mm/page_alloc.c:4598
alloc_pages_mpol+0x299/0x990 mm/mempolicy.c:2264
alloc_pages+0x1bf/0x1e0 mm/mempolicy.c:2335
dump_user_range+0x4a/0xee0 fs/coredump.c:940
elf_core_dump+0x57c7/0x5ae0 fs/binfmt_elf.c:2083
do_coredump+0x32d5/0x4920 fs/coredump.c:769
get_signal+0x267e/0x2d00 kernel/signal.c:2896
arch_do_signal_or_restart+0x53/0xcb0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x5d/0x160 kernel/entry/common.c:218
do_syscall_64+0xdc/0x1e0 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
CPU: 0 PID: 5368 Comm: segctord Not tainted 6.9.0-syzkaller-02707-g614da38e2f7a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
=====================================================
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at [email protected].
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
On Sun, Jun 16, 2024 at 4:43 AM syzbot wrote:
>
> Hello,
>
> syzbot found the following issue on:
>
> HEAD commit: 614da38e2f7a Merge tag 'hid-for-linus-2024051401' of git:/..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=12d26ada980000
> kernel config: https://syzkaller.appspot.com/x/.config?x=f5d2cbf33633f507
> dashboard link: https://syzkaller.appspot.com/bug?extid=206133fb2e7b32bba4be
> compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
>
> Unfortunately, I don't have any reproducer for this issue yet.
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/89eafb874b71/disk-614da38e.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/356000512ad9/vmlinux-614da38e.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/839c73939115/bzImage-614da38e.xz
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: [email protected]
>
> =====================================================
> BUG: KMSAN: uninit-value in crc32_body lib/crc32.c:110 [inline]
> BUG: KMSAN: uninit-value in crc32_le_generic lib/crc32.c:179 [inline]
> BUG: KMSAN: uninit-value in crc32_le_base+0x43c/0xd80 lib/crc32.c:197
> crc32_body lib/crc32.c:110 [inline]
> crc32_le_generic lib/crc32.c:179 [inline]
> crc32_le_base+0x43c/0xd80 lib/crc32.c:197
> nilfs_segbuf_fill_in_data_crc fs/nilfs2/segbuf.c:224 [inline]
> nilfs_add_checksums_on_logs+0xb80/0xe40 fs/nilfs2/segbuf.c:327
> nilfs_segctor_do_construct+0x9876/0xdeb0 fs/nilfs2/segment.c:2078
> nilfs_segctor_construct+0x1eb/0xe30 fs/nilfs2/segment.c:2381
> nilfs_segctor_thread_construct fs/nilfs2/segment.c:2489 [inline]
> nilfs_segctor_thread+0xc50/0x11e0 fs/nilfs2/segment.c:2573
> kthread+0x3e2/0x540 kernel/kthread.c:389
> ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
> ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
>
> Uninit was stored to memory at:
> memcpy_from_iter lib/iov_iter.c:73 [inline]
> iterate_bvec include/linux/iov_iter.h:122 [inline]
> iterate_and_advance2 include/linux/iov_iter.h:249 [inline]
> iterate_and_advance include/linux/iov_iter.h:271 [inline]
> __copy_from_iter lib/iov_iter.c:249 [inline]
> copy_page_from_iter_atomic+0x12b7/0x2ae0 lib/iov_iter.c:481
> generic_perform_write+0x4c1/0xc60 mm/filemap.c:3982
> __generic_file_write_iter+0x20a/0x460 mm/filemap.c:4069
> generic_file_write_iter+0x103/0x5b0 mm/filemap.c:4095
> __kernel_write_iter+0x64d/0xc80 fs/read_write.c:523
> dump_emit_page fs/coredump.c:895 [inline]
> dump_user_range+0x8dc/0xee0 fs/coredump.c:956
> elf_core_dump+0x57c7/0x5ae0 fs/binfmt_elf.c:2083
> do_coredump+0x32d5/0x4920 fs/coredump.c:769
> get_signal+0x267e/0x2d00 kernel/signal.c:2896
> arch_do_signal_or_restart+0x53/0xcb0 arch/x86/kernel/signal.c:310
> exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
> exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
> __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
> syscall_exit_to_user_mode+0x5d/0x160 kernel/entry/common.c:218
> do_syscall_64+0xdc/0x1e0 arch/x86/entry/common.c:89
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
>
> Uninit was created at:
> __alloc_pages+0x9d6/0xe70 mm/page_alloc.c:4598
> alloc_pages_mpol+0x299/0x990 mm/mempolicy.c:2264
> alloc_pages+0x1bf/0x1e0 mm/mempolicy.c:2335
> dump_user_range+0x4a/0xee0 fs/coredump.c:940
> elf_core_dump+0x57c7/0x5ae0 fs/binfmt_elf.c:2083
> do_coredump+0x32d5/0x4920 fs/coredump.c:769
> get_signal+0x267e/0x2d00 kernel/signal.c:2896
> arch_do_signal_or_restart+0x53/0xcb0 arch/x86/kernel/signal.c:310
> exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
> exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
> __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
> syscall_exit_to_user_mode+0x5d/0x160 kernel/entry/common.c:218
> do_syscall_64+0xdc/0x1e0 arch/x86/entry/common.c:89
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
>
> CPU: 0 PID: 5368 Comm: segctord Not tainted 6.9.0-syzkaller-02707-g614da38e2f7a #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
> =====================================================
>
>
> ---
> This report is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at [email protected].
>
> syzbot will keep track of this issue. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>
> If the report is already addressed, let syzbot know by replying with:
> #syz fix: exact-commit-title
>
> If you want to overwrite report's subsystems, reply with:
> #syz set subsystems: new-subsystem
> (See the list of subsystem names on the web dashboard)
>
> If the report is a duplicate of another one, reply with:
> #syz dup: exact-subject-of-another-report
>
> If you want to undo deduplication, reply with:
> #syz undup
Ah, this issue appears to be the same as the following issue where a
memory dump generated by elf_core_dump() gets mixed into the
filesystem:
https://syzkaller.appspot.com/bug?extid=47a017c46edb25eff048
However, the kernel that syzbot tested had the common fix for this
issue, commit 61b258b0d2f6 ("x86: call instrumentation hooks from
copy_mc.c") applied. So the patch may not have fixed the issue.
Ryusuke Konishi