[syzbot] [ntfs?] KASAN: use-after-free Write in ntfs_perform_write

syzbot
2024-01-09T18:19:31Z

Hello,

syzbot found the following issue on:

HEAD commit: aafe7ad77b91 Merge branch 'for-next/core' into for-kernelci
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=154cf661e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=23ce86eb3d78ef4d
dashboard link: https://syzkaller.appspot.com/bug?extid=f583da5774d7dd400312
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=149ca405e80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12172d89e80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/23845238c49b/disk-aafe7ad7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1144b0f74104/vmlinux-aafe7ad7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6db20df213a2/Image-aafe7ad7.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/475f587fffbd/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f583da5774d7dd400312@syzkaller.appspotmail.com

ntfs: (device loop0): parse_options(): Option utf8 is no longer supported, using option nls=utf8. Please use option nls=utf8 in the future and make sure utf8 is compiled either as a module or into the kernel.
ntfs: volume version 3.1.
==================================================================
BUG: KASAN: use-after-free in ntfs_commit_pages_after_write fs/ntfs/file.c:1597 [inline]
BUG: KASAN: use-after-free in ntfs_perform_write+0x5354/0x82c8 fs/ntfs/file.c:1853
Write of size 1 at addr ffff0000de9b6170 by task syz-executor306/6098

CPU: 0 PID: 6098 Comm: syz-executor306 Not tainted 6.7.0-rc6-syzkaller-gaafe7ad77b91 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Call trace:
dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:291
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:298
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:364 [inline]
print_report+0x174/0x514 mm/kasan/report.c:475
kasan_report+0xd8/0x138 mm/kasan/report.c:588
kasan_check_range+0x254/0x294 mm/kasan/generic.c:187
__asan_memcpy+0x54/0x84 mm/kasan/shadow.c:106
ntfs_commit_pages_after_write fs/ntfs/file.c:1597 [inline]
ntfs_perform_write+0x5354/0x82c8 fs/ntfs/file.c:1853
ntfs_file_write_iter+0xf3c/0x1738 fs/ntfs/file.c:1909
call_write_iter include/linux/fs.h:2020 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x610/0x910 fs/read_write.c:584
ksys_write+0x15c/0x26c fs/read_write.c:637
__do_sys_write fs/read_write.c:649 [inline]
__se_sys_write fs/read_write.c:646 [inline]
__arm64_sys_write+0x7c/0x90 fs/read_write.c:646
__invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155
el0_svc+0x54/0x158 arch/arm64/kernel/entry-common.c:678
el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595

The buggy address belongs to the physical page:
page:000000003d2e8ed5 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x11e9b6
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 05ffc00000000000 fffffc00037a6dc8 fffffc00037a6d48 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff0000de9b6000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff0000de9b6080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff0000de9b6100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff0000de9b6180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff0000de9b6200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================

---
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