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UBSAN: array-index-out-of-bounds in dtSplitPage

Status: upstream: reported C repro on 2024/12/30 07:45
Reported-by: syzbot+a0acccd8e6068831fd3b@syzkaller.appspotmail.com
First crash: 138d, last: 5d06h
▶ ▼ Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-use-after-free Write in dtSplitPage jfs C inconclusive 794 12m 153d 0/28 upstream: reported C repro on 2024/12/15 23:15
linux-5.15 UBSAN: array-index-out-of-bounds in dtSplitPage origin:upstream C 29 10h46m 139d 0/3 upstream: reported C repro on 2024/12/29 06:57

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in dtMoveEntry fs/jfs/jfs_dtree.c:3922 [inline]
BUG: KASAN: use-after-free in dtSplitPage+0x1aba/0x31d0 fs/jfs/jfs_dtree.c:1561
Write of size 1 at addr ffff88807a274000 by task syz-executor170/4259

CPU: 1 PID: 4259 Comm: syz-executor170 Not tainted 6.1.138-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0xa8/0x220 mm/kasan/report.c:427
 kasan_report+0x10b/0x140 mm/kasan/report.c:531
 dtMoveEntry fs/jfs/jfs_dtree.c:3922 [inline]
 dtSplitPage+0x1aba/0x31d0 fs/jfs/jfs_dtree.c:1561
 dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline]
 dtInsert+0xfbd/0x58a0 fs/jfs/jfs_dtree.c:871
 jfs_create+0x69d/0xa50 fs/jfs/namei.c:137
 lookup_open fs/namei.c:3482 [inline]
 open_last_lookups fs/namei.c:3550 [inline]
 path_openat+0x1187/0x2e70 fs/namei.c:3780
 do_filp_open+0x1c1/0x3c0 fs/namei.c:3810
 do_sys_openat2+0x142/0x490 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_creat fs/open.c:1412 [inline]
 __se_sys_creat fs/open.c:1406 [inline]
 __x64_sys_creat+0x8c/0xb0 fs/open.c:1406
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f95a28a9929
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 71 1d 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f95a203b218 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f95a2930638 RCX: 00007f95a28a9929
RDX: 00007f95a28a9929 RSI: 0000000000000000 RDI: 00002000000006c0
RBP: 00007f95a2930630 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f95a28fc45c
R13: 0000200000000080 R14: 00002000000008c0 R15: 00002000000006c0
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0001e89d00 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7a274
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea00009dd088 ffffea0001e89d88 0000000000000000
raw: 0000000000000000 0000000000100000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3962, tgid 3962 (dhcpcd-run-hook), ts 57205764727, free_ts 86539493011
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532
 prep_new_page mm/page_alloc.c:2539 [inline]
 get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328
 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5606
 alloc_slab_page+0x5d/0x160 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x87/0x2c0 mm/slub.c:1992
 ___slab_alloc+0xbc6/0x1220 mm/slub.c:3180
 kmem_cache_alloc_bulk+0x1a3/0x4e0 mm/slub.c:3830
 mt_alloc_bulk lib/maple_tree.c:157 [inline]
 mas_alloc_nodes+0x449/0x890 lib/maple_tree.c:1299
 mas_node_count_gfp lib/maple_tree.c:1359 [inline]
 mas_preallocate+0x11e/0x340 lib/maple_tree.c:5805
 __vma_adjust+0x2e2/0x1bd0 mm/mmap.c:723
 vma_adjust include/linux/mm.h:2742 [inline]
 __split_vma+0x3a7/0x500 mm/mmap.c:-1
 do_mas_align_munmap+0x351/0x1220 mm/mmap.c:2468
 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2638
 __mmap_region mm/mmap.c:2686 [inline]
 mmap_region+0x713/0x1d30 mm/mmap.c:2904
 do_mmap+0x894/0xf30 mm/mmap.c:1424
 vm_mmap_pgoff+0x1b2/0x2b0 mm/util.c:520
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 mm/page_alloc.c:1509 [inline]
 free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384
 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 __kmem_cache_alloc_node+0x140/0x260 mm/slub.c:3437
 kmalloc_node_trace+0x22/0xe0 mm/slab_common.c:1039
 kmalloc_node include/linux/slab.h:585 [inline]
 kzalloc_node include/linux/slab.h:710 [inline]
 alloc_worker kernel/workqueue.c:1843 [inline]
 create_worker+0x10f/0x630 kernel/workqueue.c:1940
 maybe_create_worker kernel/workqueue.c:2110 [inline]
 manage_workers kernel/workqueue.c:2162 [inline]
 worker_thread+0x4de/0x1250 kernel/workqueue.c:2411
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Memory state around the buggy address:
 ffff88807a273f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807a273f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88807a274000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88807a274080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88807a274100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================

Crashes (17):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/12 10:04 linux-6.1.y 02b72ccb5f9d 77908e5f .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)] ci2-linux-6-1-kasan KASAN: use-after-free Write in dtSplitPage
2025/04/21 19:27 linux-6.1.y 420102835862 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dtSplitPage
2025/04/14 17:07 linux-6.1.y 420102835862 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dtSplitPage
2025/04/11 00:38 linux-6.1.y 420102835862 1ef3ab4d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dtSplitPage
2025/03/22 07:45 linux-6.1.y 344a09659766 c6512ef7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dtSplitPage
2025/03/20 11:18 linux-6.1.y 344a09659766 9209bc22 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dtSplitPage
2025/01/03 08:56 linux-6.1.y 7dc732d24ff7 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dtSplitPage
2024/12/31 23:08 linux-6.1.y 563edd786f0a d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dtSplitPage
2024/12/31 19:25 linux-6.1.y 563edd786f0a d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dtSplitPage
2024/12/30 07:45 linux-6.1.y 563edd786f0a d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan UBSAN: array-index-out-of-bounds in dtSplitPage
2025/05/12 21:22 linux-6.1.y 02b72ccb5f9d f6671af7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: slab-out-of-bounds Write in dtSplitPage
2025/05/12 21:22 linux-6.1.y 02b72ccb5f9d f6671af7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Write in dtSplitPage
2025/05/12 08:56 linux-6.1.y 02b72ccb5f9d 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Write in dtSplitPage
2025/04/15 06:22 linux-6.1.y 420102835862 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: slab-out-of-bounds Read in dtSplitPage
2025/04/29 12:21 linux-6.1.y 535ec20c5027 aeb6ec69 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: slab-out-of-bounds Read in dtSplitPage
2025/04/23 15:28 linux-6.1.y 420102835862 53a8b9bd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: slab-out-of-bounds Read in dtSplitPage
2025/04/15 05:24 linux-6.1.y 420102835862 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: slab-out-of-bounds Read in dtSplitPage
* Struck through repros no longer work on HEAD.