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KASAN: use-after-free Read in ntfs_iget5

Status: auto-obsoleted due to no activity on 2023/12/20 11:31
Reported-by: syzbot+127bb5d8ccc2445427a0@syzkaller.appspotmail.com
First crash: 915d, last: 774d
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 KASAN: use-after-free Read in ntfs_iget5 19 7 707d 954d 0/3 auto-obsoleted due to no activity on 2024/02/25 08:58
linux-5.15 KASAN: slab-out-of-bounds Read in ntfs_iget5 19 31 64d 325d 0/3 upstream: reported on 2024/12/03 01:28
linux-5.15 KASAN: use-after-free Read in ntfs_iget5 (2) 19 5 471d 571d 0/3 auto-obsoleted due to no activity on 2024/10/18 06:28
upstream KASAN: slab-out-of-bounds Read in ntfs_iget5 ntfs3 19 C done done 3633 647d 1281d 25/29 fixed on 2024/03/20 11:33
linux-6.1 KASAN: use-after-free Read in ntfs_iget5 (2) origin:upstream 19 C error 41 1d07h 574d 0/3 upstream: reported C repro on 2024/03/29 09:18
linux-6.6 KASAN: slab-use-after-free Read in ntfs_iget5 19 4 18d 66d 0/2 upstream: reported on 2025/08/19 13:23
upstream BUG: unable to handle kernel paging request in ntfs_iget5 ntfs3 8 1 530d 526d 0/29 auto-obsoleted due to no activity on 2024/08/10 16:42

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in ntfs_iget5+0x154/0x3900 fs/ntfs3/inode.c:525
Read of size 8 at addr ffff8880259ffdd0 by task syz-executor.3/16244

CPU: 1 PID: 16244 Comm: syz-executor.3 Not tainted 5.15.130-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 ntfs_iget5+0x154/0x3900 fs/ntfs3/inode.c:525
 ntfs_fill_super+0x1c7c/0x4450 fs/ntfs3/super.c:941
 get_tree_bdev+0x3fe/0x620 fs/super.c:1312
 vfs_get_tree+0x88/0x270 fs/super.c:1517
 do_new_mount+0x28b/0xae0 fs/namespace.c:2994
 do_mount fs/namespace.c:3337 [inline]
 __do_sys_mount fs/namespace.c:3545 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3522
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fc0c096b1ea
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 09 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc0beeeaee8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fc0beeeaf80 RCX: 00007fc0c096b1ea
RDX: 0000000020000000 RSI: 000000002001f1c0 RDI: 00007fc0beeeaf40
RBP: 0000000020000000 R08: 00007fc0beeeaf80 R09: 0000000001014085
R10: 0000000001014085 R11: 0000000000000202 R12: 000000002001f1c0
R13: 00007fc0beeeaf40 R14: 000000000001f1ae R15: 0000000020000140
 </TASK>

Allocated by task 15976:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 __kasan_slab_alloc+0x8e/0xc0 mm/kasan/common.c:467
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x53/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3220 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0xf3/0x280 mm/slub.c:3233
 btrfs_alloc_inode+0x4c/0x470 fs/btrfs/inode.c:9193
 alloc_inode fs/inode.c:236 [inline]
 new_inode_pseudo+0x60/0x210 fs/inode.c:937
 new_inode+0x25/0x1d0 fs/inode.c:966
 btrfs_new_inode+0x1c5/0x1c10 fs/btrfs/inode.c:6510
 btrfs_create+0x32d/0x680 fs/btrfs/inode.c:6845
 lookup_open fs/namei.c:3392 [inline]
 open_last_lookups fs/namei.c:3462 [inline]
 path_openat+0x12f6/0x2f20 fs/namei.c:3669
 do_filp_open+0x21c/0x460 fs/namei.c:3699
 do_sys_openat2+0x13b/0x500 fs/open.c:1211
 do_sys_open fs/open.c:1227 [inline]
 __do_sys_openat fs/open.c:1243 [inline]
 __se_sys_openat fs/open.c:1238 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1238
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Last potentially related work creation:
 kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348
 __call_rcu kernel/rcu/tree.c:2994 [inline]
 call_rcu+0x1c4/0xa70 kernel/rcu/tree.c:3074
 dispose_list fs/inode.c:620 [inline]
 evict_inodes+0x601/0x6a0 fs/inode.c:670
 generic_shutdown_super+0x99/0x2c0 fs/super.c:454
 kill_anon_super+0x37/0x60 fs/super.c:1076
 btrfs_kill_super+0x3d/0x50 fs/btrfs/super.c:2391
 deactivate_locked_super+0xa0/0x110 fs/super.c:335
 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143
 task_work_run+0x129/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:175
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x5d/0x250 kernel/entry/common.c:301
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Second to last potentially related work creation:
 kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348
 __call_rcu kernel/rcu/tree.c:2994 [inline]
 call_rcu+0x1c4/0xa70 kernel/rcu/tree.c:3074
 dispose_list fs/inode.c:620 [inline]
 evict_inodes+0x601/0x6a0 fs/inode.c:670
 generic_shutdown_super+0x99/0x2c0 fs/super.c:454
 kill_anon_super+0x37/0x60 fs/super.c:1076
 btrfs_kill_super+0x3d/0x50 fs/btrfs/super.c:2391
 deactivate_locked_super+0xa0/0x110 fs/super.c:335
 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143
 task_work_run+0x129/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:175
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x5d/0x250 kernel/entry/common.c:301
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

The buggy address belongs to the object at ffff8880259ff5c0
 which belongs to the cache btrfs_inode of size 2384
The buggy address is located 2064 bytes inside of
 2384-byte region [ffff8880259ff5c0, ffff8880259fff10)
The buggy address belongs to the page:
page:ffffea0000967e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880259fe220 pfn:0x259f8
head:ffffea0000967e00 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff88801c70a601
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001c64e00 0000000200000002 ffff88814b65a140
raw: ffff8880259fe220 00000000800d0005 00000001ffffffff ffff88801c70a601
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 4087, ts 145665092407, free_ts 0
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5421
 alloc_slab_page mm/slub.c:1775 [inline]
 allocate_slab mm/slub.c:1912 [inline]
 new_slab+0xbb/0x4b0 mm/slub.c:1975
 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008
 __slab_alloc mm/slub.c:3095 [inline]
 slab_alloc_node mm/slub.c:3186 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0x18e/0x280 mm/slub.c:3233
 btrfs_alloc_inode+0x4c/0x470 fs/btrfs/inode.c:9193
 alloc_inode fs/inode.c:236 [inline]
 iget5_locked+0x9c/0x260 fs/inode.c:1199
 btrfs_iget_locked fs/btrfs/inode.c:5930 [inline]
 btrfs_iget_path+0x164/0x16b0 fs/btrfs/inode.c:5947
 btrfs_fill_super+0x206/0x2d0 fs/btrfs/super.c:1393
 btrfs_mount_root+0x803/0x930 fs/btrfs/super.c:1752
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1517
 fc_mount fs/namespace.c:1000 [inline]
 vfs_kern_mount+0xb8/0x150 fs/namespace.c:1030
 btrfs_mount+0x395/0xb40 fs/btrfs/super.c:1812
 legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
 vfs_get_tree+0x88/0x270 fs/super.c:1517
page_owner free stack trace missing

Memory state around the buggy address:
 ffff8880259ffc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880259ffd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880259ffd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff8880259ffe00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880259ffe80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/09/05 04:18 linux-5.15.y 8f790700c974 0b6286dc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ntfs_iget5
2023/06/29 14:47 linux-5.15.y 4af60700a60c 134ddc02 .config console log report info ci2-linux-5-15-kasan KASAN: use-after-free Read in ntfs_iget5
2023/04/23 10:28 linux-5.15.y 3299fb36854f 2b32bd34 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in ntfs_iget5
2023/04/24 05:20 linux-5.15.y 3299fb36854f 2b32bd34 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 KASAN: use-after-free Read in ntfs_iget5
2023/09/11 11:30 linux-5.15.y aff03380bda4 59da8366 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: slab-out-of-bounds Read in ntfs_iget5
* Struck through repros no longer work on HEAD.