syzbot


KASAN: slab-out-of-bounds Read in hdr_delete_de

Status: upstream: reported C repro on 2022/12/06 08:52
Reported-by: syzbot+9c2811fd56591639ff5f@syzkaller.appspotmail.com
Fix commit: fs/ntfs3: Fix slab-out-of-bounds read in hdr_delete_de()
Patched on: [ci-upstream-linux-next-kasan-gce-root], missing on: [ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-qemu2-riscv64 ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-arm64 ci-upstream-gce-leak ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-kmsan-gce ci-upstream-kmsan-gce-386 ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb]
First crash: 62d, last: 62d

Cause bisection: failed (bisect log)

Sample crash report:
loop0: detected capacity change from 0 to 4096
ntfs3: loop0: Different NTFS' sector size (2048) and media sector size (512)
==================================================================
BUG: KASAN: slab-out-of-bounds in hdr_delete_de+0xe0/0x150 fs/ntfs3/index.c:806
Read of size 16842960 at addr ffff888079cc0600 by task syz-executor934/3631

CPU: 0 PID: 3631 Comm: syz-executor934 Not tainted 6.1.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
 print_address_description+0x74/0x340 mm/kasan/report.c:284
 print_report+0x107/0x1f0 mm/kasan/report.c:395
 kasan_report+0xcd/0x100 mm/kasan/report.c:495
 kasan_check_range+0x2a7/0x2e0 mm/kasan/generic.c:189
 memmove+0x25/0x60 mm/kasan/shadow.c:54
 hdr_delete_de+0xe0/0x150 fs/ntfs3/index.c:806
 indx_delete_entry+0x74f/0x3670 fs/ntfs3/index.c:2193
 ni_remove_name+0x27a/0x980 fs/ntfs3/frecord.c:2910
 ntfs_unlink_inode+0x3d4/0x720 fs/ntfs3/inode.c:1712
 ntfs_rename+0x41a/0xcb0 fs/ntfs3/namei.c:276
 vfs_rename+0xd53/0x1130 fs/namei.c:4779
 do_renameat2+0xb53/0x1370 fs/namei.c:4930
 __do_sys_rename fs/namei.c:4976 [inline]
 __se_sys_rename fs/namei.c:4974 [inline]
 __x64_sys_rename+0x82/0x90 fs/namei.c:4974
 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+0x63/0xcd
RIP: 0033:0x7fb16d7e97c9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdc864b578 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 0031656c69662f2e RCX: 00007fb16d7e97c9
RDX: 0000000000000030 RSI: 0000000020000080 RDI: 0000000020000040
RBP: 00007fb16d7a9060 R08: 000000000001f376 R09: 0000000000000000
R10: 00007ffdc864b440 R11: 0000000000000246 R12: 00007fb16d7a90f0
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Allocated by task 3631:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x3d/0x60 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:371 [inline]
 __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:380
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:955 [inline]
 __kmalloc+0xaf/0x1a0 mm/slab_common.c:968
 kmalloc include/linux/slab.h:558 [inline]
 indx_read+0x29a/0x880 fs/ntfs3/index.c:978
 indx_find+0x491/0xb20 fs/ntfs3/index.c:1080
 indx_delete_entry+0x460/0x3670 fs/ntfs3/index.c:2167
 ni_remove_name+0x27a/0x980 fs/ntfs3/frecord.c:2910
 ntfs_unlink_inode+0x3d4/0x720 fs/ntfs3/inode.c:1712
 ntfs_rename+0x41a/0xcb0 fs/ntfs3/namei.c:276
 vfs_rename+0xd53/0x1130 fs/namei.c:4779
 do_renameat2+0xb53/0x1370 fs/namei.c:4930
 __do_sys_rename fs/namei.c:4976 [inline]
 __se_sys_rename fs/namei.c:4974 [inline]
 __x64_sys_rename+0x82/0x90 fs/namei.c:4974
 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+0x63/0xcd

The buggy address belongs to the object at ffff888079cc0000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 1536 bytes inside of
 4096-byte region [ffff888079cc0000, ffff888079cc1000)

The buggy address belongs to the physical page:
page:ffffea0001e73000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x79cc0
head:ffffea0001e73000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888012842140
raw: 0000000000000000 0000000080040004 00000001ffffffff 0000000000000000
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 2999, tgid 2999 (udevd), ts 25263182361, free_ts 19241901550
 prep_new_page mm/page_alloc.c:2539 [inline]
 get_page_from_freelist+0x742/0x7c0 mm/page_alloc.c:4291
 __alloc_pages+0x259/0x560 mm/page_alloc.c:5558
 alloc_slab_page+0xbd/0x190 mm/slub.c:1794
 allocate_slab+0x5e/0x4b0 mm/slub.c:1939
 new_slab mm/slub.c:1992 [inline]
 ___slab_alloc+0x782/0xe20 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 __kmem_cache_alloc_node+0x252/0x310 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:954 [inline]
 __kmalloc+0x9e/0x1a0 mm/slab_common.c:968
 kmalloc include/linux/slab.h:558 [inline]
 tomoyo_realpath_from_path+0xcd/0x5f0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x227/0x670 security/tomoyo/file.c:822
 security_inode_getattr+0xc0/0x140 security/security.c:1347
 vfs_getattr fs/stat.c:158 [inline]
 vfs_statx+0x188/0x4a0 fs/stat.c:233
 vfs_fstatat fs/stat.c:267 [inline]
 __do_sys_newfstatat fs/stat.c:437 [inline]
 __se_sys_newfstatat+0xed/0x7d0 fs/stat.c:431
 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+0x63/0xcd
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1459 [inline]
 free_pcp_prepare+0x80c/0x8f0 mm/page_alloc.c:1509
 free_unref_page_prepare mm/page_alloc.c:3387 [inline]
 free_unref_page+0x7d/0x5f0 mm/page_alloc.c:3483
 free_slab mm/slub.c:2031 [inline]
 discard_slab mm/slub.c:2037 [inline]
 __unfreeze_partials+0x1ab/0x200 mm/slub.c:2586
 put_cpu_partial+0x106/0x170 mm/slub.c:2662
 qlist_free_all+0x2b/0x70 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x169/0x180 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:302
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slab.h:737 [inline]
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x1cc/0x300 mm/slub.c:3422
 vm_area_alloc+0x20/0xe0 kernel/fork.c:458
 mmap_region+0xd38/0x1e20 mm/mmap.c:2602
 do_mmap+0x8d9/0xf30 mm/mmap.c:1412
 vm_mmap_pgoff+0x19e/0x2b0 mm/util.c:520
 ksys_mmap_pgoff+0x48c/0x6d0 mm/mmap.c:1458
 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+0x63/0xcd

Memory state around the buggy address:
 ffff888079cc0f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888079cc0f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888079cc1000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff888079cc1080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888079cc1100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (2):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci2-upstream-fs 2022/12/06 02:11 upstream 76dcd734eca2 045cbb84 .config strace log report syz C [disk image] [vmlinux] [kernel image] [mounted in repro] KASAN: slab-out-of-bounds Read in hdr_delete_de
ci2-upstream-fs 2022/12/06 01:54 upstream 76dcd734eca2 045cbb84 .config console log report info [disk image] [vmlinux] [kernel image] KASAN: slab-out-of-bounds Read in hdr_delete_de
* Struck through repros no longer work on HEAD.