[moderation] [ntfs3?] KASAN: slab-out-of-bounds Write in ntfs_read_run_nb

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 260f6f4fda93 Merge tag 'drm-next-2025-07-30' of https://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14762f82580000
kernel config: https://syzkaller.appspot.com/x/.config?x=bb7581d3fb1bb0d7
dashboard link: https://syzkaller.appspot.com/bug?extid=32a6974849591bdb881d
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
CC: [almaz.ale...@paragon-software.com linux-...@vger.kernel.org nt...@lists.linux.dev]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1fce1d4d56ce/disk-260f6f4f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/01688cdba884/vmlinux-260f6f4f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/eba9b2f77e6a/bzImage-260f6f4f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+32a697...@syzkaller.appspotmail.com

loop6: detected capacity change from 0 to 4096
==================================================================
BUG: KASAN: slab-out-of-bounds in ntfs_read_run_nb+0x4e2/0xdb0 fs/ntfs3/fsntfs.c:1232
Write of size 1024 at addr ffff888030108000 by task syz.6.212/7662

CPU: 1 UID: 0 PID: 7662 Comm: syz.6.212 Tainted: G W 6.16.0-syzkaller-08685-g260f6f4fda93 #0 PREEMPT_{RT,(full)}
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
<TASK>
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xca/0x240 mm/kasan/report.c:482
kasan_report+0x118/0x150 mm/kasan/report.c:595
check_region_inline mm/kasan/generic.c:-1 [inline]
kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:189
__asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106
ntfs_read_run_nb+0x4e2/0xdb0 fs/ntfs3/fsntfs.c:1232
ntfs_read_bh+0x40/0x7e0 fs/ntfs3/fsntfs.c:1293
mi_read+0x194/0x5a0 fs/ntfs3/record.c:133
ntfs_read_mft fs/ntfs3/inode.c:70 [inline]
ntfs_iget5+0x45b/0x37c0 fs/ntfs3/inode.c:540
ntfs_fill_super+0x3927/0x40b0 fs/ntfs3/super.c:1519
get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1692
vfs_get_tree+0x8f/0x2b0 fs/super.c:1815
do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
do_mount fs/namespace.c:4133 [inline]
__do_sys_mount fs/namespace.c:4344 [inline]
__se_sys_mount+0x317/0x410 fs/namespace.c:4321
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0665e0030a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0663c65e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f0663c65ef0 RCX: 00007f0665e0030a
RDX: 0000200000000080 RSI: 000020000001f740 RDI: 00007f0663c65eb0
RBP: 0000200000000080 R08: 00007f0663c65ef0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000020000001f740
R13: 00007f0663c65eb0 R14: 000000000001f756 R15: 00002000000000c0
</TASK>

Allocated by task 7662:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4364 [inline]
__kmalloc_noprof+0x1ef/0x430 mm/slub.c:4376
kmalloc_noprof include/linux/slab.h:909 [inline]
mi_init+0x76/0xe0 fs/ntfs3/record.c:105
ntfs_read_mft fs/ntfs3/inode.c:54 [inline]
ntfs_iget5+0x356/0x37c0 fs/ntfs3/inode.c:540
ntfs_fill_super+0x3927/0x40b0 fs/ntfs3/super.c:1519
get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1692
vfs_get_tree+0x8f/0x2b0 fs/super.c:1815
do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
do_mount fs/namespace.c:4133 [inline]
__do_sys_mount fs/namespace.c:4344 [inline]
__se_sys_mount+0x317/0x410 fs/namespace.c:4321
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888030108000
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 0 bytes inside of
allocated 1023-byte region [ffff888030108000, ffff8880301083ff)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x30108
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff888019841dc0 dead000000000122 0000000000000000
raw: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000
head: 0080000000000040 ffff888019841dc0 dead000000000122 0000000000000000
head: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000
head: 0080000000000003 ffffea0000c04201 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 7662, tgid 7659 (syz.6.212), ts 333360260697, free_ts 333302180837
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704
prep_new_page mm/page_alloc.c:1712 [inline]
get_page_from_freelist+0x2119/0x21b0 mm/page_alloc.c:3669
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959
alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2419
alloc_slab_page mm/slub.c:2486 [inline]
allocate_slab+0x8a/0x370 mm/slub.c:2654
new_slab mm/slub.c:2708 [inline]
___slab_alloc+0x8d1/0xdd0 mm/slub.c:3890
__slab_alloc mm/slub.c:3980 [inline]
__slab_alloc_node mm/slub.c:4055 [inline]
slab_alloc_node mm/slub.c:4216 [inline]
__do_kmalloc_node mm/slub.c:4363 [inline]
__kmalloc_noprof+0x145/0x430 mm/slub.c:4376
kmalloc_noprof include/linux/slab.h:909 [inline]
mi_init+0x76/0xe0 fs/ntfs3/record.c:105
ntfs_read_mft fs/ntfs3/inode.c:54 [inline]
ntfs_iget5+0x356/0x37c0 fs/ntfs3/inode.c:540
ntfs_fill_super+0x3927/0x40b0 fs/ntfs3/super.c:1519
get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1692
vfs_get_tree+0x8f/0x2b0 fs/super.c:1815
do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805
do_mount fs/namespace.c:4133 [inline]
__do_sys_mount fs/namespace.c:4344 [inline]
__se_sys_mount+0x317/0x410 fs/namespace.c:4321
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 7683 tgid 7683 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1248 [inline]
__free_frozen_pages+0xbe5/0xdf0 mm/page_alloc.c:2706
discard_slab mm/slub.c:2752 [inline]
__put_partials+0x159/0x1a0 mm/slub.c:3217
__slab_free+0x2b3/0x390 mm/slub.c:4549
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4179 [inline]
slab_alloc_node mm/slub.c:4228 [inline]
kmem_cache_alloc_noprof+0x143/0x310 mm/slub.c:4235
vm_area_alloc+0x24/0x140 mm/vma_init.c:31
__install_special_mapping mm/mmap.c:1453 [inline]
_install_special_mapping+0x2e/0x350 mm/mmap.c:1501
map_vdso+0x1ff/0x480 arch/x86/entry/vdso/vma.c:172
load_elf_binary+0x1c40/0x2750 fs/binfmt_elf.c:1276
search_binary_handler fs/exec.c:1670 [inline]
exec_binprm fs/exec.c:1702 [inline]
bprm_execve+0x99c/0x1440 fs/exec.c:1754
do_execveat_common+0x510/0x6a0 fs/exec.c:1860
do_execve fs/exec.c:1934 [inline]
__do_sys_execve fs/exec.c:2010 [inline]
__se_sys_execve fs/exec.c:2005 [inline]
__x64_sys_execve+0x94/0xb0 fs/exec.c:2005
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
ffff888030108280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff888030108300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888030108380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 07
^
ffff888030108400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888030108480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================


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