Hello,
syzbot found the following issue on:
HEAD commit: bb9c90ab9c5a Linux 6.6.102
git tree: linux-6.6.y
console output:
https://syzkaller.appspot.com/x/log.txt?x=12bcdba2580000
kernel config:
https://syzkaller.appspot.com/x/.config?x=7b989b97a0687b0a
dashboard link:
https://syzkaller.appspot.com/bug?extid=6d08037c33272de1e5a0
compiler: Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image:
https://storage.googleapis.com/syzbot-assets/44e2224124c3/disk-bb9c90ab.raw.xz
vmlinux:
https://storage.googleapis.com/syzbot-assets/33e0aef7ff42/vmlinux-bb9c90ab.xz
kernel image:
https://storage.googleapis.com/syzbot-assets/0515bc436228/bzImage-bb9c90ab.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by:
syzbot+6d0803...@syzkaller.appspotmail.com
loop0: detected capacity change from 0 to 4096
==================================================================
BUG: KASAN: slab-use-after-free in ntfs_iget5+0x152/0x3750 fs/ntfs3/inode.c:534
Read of size 8 at addr ffff8880754a0600 by task syz.0.3813/14734
CPU: 1 PID: 14734 Comm: syz.0.3813 Not tainted 6.6.102-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
<TASK>
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:364 [inline]
print_report+0xac/0x220 mm/kasan/report.c:468
kasan_report+0x117/0x150 mm/kasan/report.c:581
ntfs_iget5+0x152/0x3750 fs/ntfs3/inode.c:534
ntfs_fill_super+0x2788/0x42e0 fs/ntfs3/super.c:1269
get_tree_bdev+0x3e4/0x510 fs/super.c:1591
vfs_get_tree+0x8c/0x280 fs/super.c:1764
do_new_mount+0x24b/0xa40 fs/namespace.c:3371
do_mount fs/namespace.c:3711 [inline]
__do_sys_mount fs/namespace.c:3920 [inline]
__se_sys_mount+0x2da/0x3c0 fs/namespace.c:3897
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f3bc7f9038a
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:00007f3bc8ddce68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f3bc8ddcef0 RCX: 00007f3bc7f9038a
RDX: 0000200000000000 RSI: 0000200000000140 RDI: 00007f3bc8ddceb0
RBP: 0000200000000000 R08: 00007f3bc8ddcef0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000140
R13: 00007f3bc8ddceb0 R14: 000000000001f8fd R15: 0000200000000080
</TASK>
Allocated by task 7042:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767
slab_alloc_node mm/slub.c:3485 [inline]
slab_alloc mm/slub.c:3493 [inline]
__kmem_cache_alloc_lru mm/slub.c:3500 [inline]
kmem_cache_alloc_lru+0x115/0x2e0 mm/slub.c:3516
alloc_inode_sb include/linux/fs.h:2946 [inline]
reiserfs_alloc_inode+0x2a/0xc0 fs/reiserfs/super.c:642
alloc_inode fs/inode.c:261 [inline]
iget5_locked+0xa2/0x260 fs/inode.c:1314
reiserfs_fill_super+0x1170/0x2340 fs/reiserfs/super.c:2053
mount_bdev+0x22b/0x2d0 fs/super.c:1643
legacy_get_tree+0xea/0x180 fs/fs_context.c:662
vfs_get_tree+0x8c/0x280 fs/super.c:1764
do_new_mount+0x24b/0xa40 fs/namespace.c:3371
do_mount fs/namespace.c:3711 [inline]
__do_sys_mount fs/namespace.c:3920 [inline]
__se_sys_mount+0x2da/0x3c0 fs/namespace.c:3897
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Last potentially related work creation:
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45
__kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492
__call_rcu_common kernel/rcu/tree.c:2721 [inline]
call_rcu+0x158/0x930 kernel/rcu/tree.c:2837
destroy_inode fs/inode.c:316 [inline]
evict+0x7db/0x870 fs/inode.c:720
reiserfs_fill_super+0x1403/0x2340 fs/reiserfs/super.c:2078
mount_bdev+0x22b/0x2d0 fs/super.c:1643
legacy_get_tree+0xea/0x180 fs/fs_context.c:662
vfs_get_tree+0x8c/0x280 fs/super.c:1764
do_new_mount+0x24b/0xa40 fs/namespace.c:3371
do_mount fs/namespace.c:3711 [inline]
__do_sys_mount fs/namespace.c:3920 [inline]
__se_sys_mount+0x2da/0x3c0 fs/namespace.c:3897
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Second to last potentially related work creation:
kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45
__kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492
__call_rcu_common kernel/rcu/tree.c:2721 [inline]
call_rcu+0x158/0x930 kernel/rcu/tree.c:2837
destroy_inode fs/inode.c:316 [inline]
evict+0x7db/0x870 fs/inode.c:720
reiserfs_fill_super+0x1403/0x2340 fs/reiserfs/super.c:2078
mount_bdev+0x22b/0x2d0 fs/super.c:1643
legacy_get_tree+0xea/0x180 fs/fs_context.c:662
vfs_get_tree+0x8c/0x280 fs/super.c:1764
do_new_mount+0x24b/0xa40 fs/namespace.c:3371
do_mount fs/namespace.c:3711 [inline]
__do_sys_mount fs/namespace.c:3920 [inline]
__se_sys_mount+0x2da/0x3c0 fs/namespace.c:3897
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
The buggy address belongs to the object at ffff8880754a0000
which belongs to the cache reiser_inode_cache of size 1568
The buggy address is located 1536 bytes inside of
freed 1568-byte region [ffff8880754a0000, ffff8880754a0620)
The buggy address belongs to the physical page:
page:ffffea0001d52800 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880754a0000 pfn:0x754a0
head:ffffea0001d52800 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff888017ebc601
flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888018391b40 dead000000000122 0000000000000000
raw: ffff8880754a0000 0000000080130012 00000001ffffffff ffff888017ebc601
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 6347, tgid 6345 (syz.2.238), ts 93235934196, free_ts 89109774618
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554
prep_new_page mm/page_alloc.c:1561 [inline]
get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191
__alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457
alloc_slab_page+0x5d/0x170 mm/slub.c:1876
allocate_slab mm/slub.c:2023 [inline]
new_slab+0x87/0x2e0 mm/slub.c:2076
___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230
__slab_alloc mm/slub.c:3329 [inline]
__slab_alloc_node mm/slub.c:3382 [inline]
slab_alloc_node mm/slub.c:3475 [inline]
slab_alloc mm/slub.c:3493 [inline]
__kmem_cache_alloc_lru mm/slub.c:3500 [inline]
kmem_cache_alloc_lru+0x1ae/0x2e0 mm/slub.c:3516
alloc_inode_sb include/linux/fs.h:2946 [inline]
reiserfs_alloc_inode+0x2a/0xc0 fs/reiserfs/super.c:642
alloc_inode fs/inode.c:261 [inline]
iget5_locked+0xa2/0x260 fs/inode.c:1314
reiserfs_fill_super+0x1170/0x2340 fs/reiserfs/super.c:2053
mount_bdev+0x22b/0x2d0 fs/super.c:1643
legacy_get_tree+0xea/0x180 fs/fs_context.c:662
vfs_get_tree+0x8c/0x280 fs/super.c:1764
do_new_mount+0x24b/0xa40 fs/namespace.c:3371
do_mount fs/namespace.c:3711 [inline]
__do_sys_mount fs/namespace.c:3920 [inline]
__se_sys_mount+0x2da/0x3c0 fs/namespace.c:3897
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1154 [inline]
free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336
free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429
__slab_free+0x35e/0x410 mm/slub.c:3722
qlink_free mm/kasan/quarantine.c:166 [inline]
qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185
kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767
slab_alloc_node mm/slub.c:3485 [inline]
__kmem_cache_alloc_node+0x13e/0x260 mm/slub.c:3524
__do_kmalloc_node mm/slab_common.c:1006 [inline]
__kmalloc+0xa4/0x240 mm/slab_common.c:1020
kmalloc include/linux/slab.h:604 [inline]
tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251
tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
tomoyo_path_perm+0x20f/0x4b0 security/tomoyo/file.c:822
security_inode_getattr+0xd3/0x120 security/security.c:2153
vfs_getattr fs/stat.c:173 [inline]
vfs_fstat fs/stat.c:198 [inline]
__do_sys_newfstat fs/stat.c:473 [inline]
__se_sys_newfstat fs/stat.c:470 [inline]
__x64_sys_newfstat+0x101/0x1f0 fs/stat.c:470
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Memory state around the buggy address:
ffff8880754a0500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880754a0580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880754a0600: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff8880754a0680: fc fc fc fc 00 00 00 00 00 00 00 00 00 00 00 00
ffff8880754a0700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
---
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