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

Date	Name	Commit	Repro	Result
2025/12/26	upstream (ToT)	ccd1cdca5cd4	C	[report] KASAN: slab-out-of-bounds Read in dtReadFirst

Date

Name

Commit

Repro

Result

2025/12/26

upstream (ToT)

ccd1cdca5cd4

[report] KASAN: slab-out-of-bounds Read in dtReadFirst

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
linux-6.1	UBSAN: array-index-out-of-bounds in dtReadFirst origin:lts-only	19	C		error	23	266d	430d	0/3	upstream: reported C repro on 2024/11/25 10:09
upstream	UBSAN: array-index-out-of-bounds in dtReadFirst jfs	19	C	error		200	410d	638d	28/29	fixed on 2024/12/16 09:50
linux-5.15	UBSAN: array-index-out-of-bounds in dtReadFirst origin:upstream	17	C		error	34	25d	640d	0/3	upstream: reported C repro on 2024/04/28 12:32
upstream	UBSAN: array-index-out-of-bounds in dtReadFirst (2) jfs	19	C	error		119	276d	404d	28/29	fixed on 2025/06/10 16:19
upstream	KASAN: slab-out-of-bounds Read in dtReadFirst jfs	19	C	error		56	11d	204d	0/29	upstream: reported C repro on 2025/07/09 11:02

syz.0.17[5930]: memfd_create() called without MFD_EXEC or MFD_NOEXEC_SEAL set loop0: detected capacity change from 0 to 32768 ================================================================== BUG: KASAN: slab-out-of-bounds in addressPXD fs/jfs/jfs_types.h:80 [inline] BUG: KASAN: slab-out-of-bounds in dtReadFirst+0x502/0x920 fs/jfs/jfs_dtree.c:3108 Read of size 4 at addr ffff88805f931210 by task syz.0.17/5930 CPU: 1 PID: 5930 Comm: syz.0.17 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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 addressPXD fs/jfs/jfs_types.h:80 [inline] dtReadFirst+0x502/0x920 fs/jfs/jfs_dtree.c:3108 jfs_readdir+0x6f6/0x3a90 fs/jfs/jfs_dtree.c:2821 wrap_directory_iterator+0x92/0xd0 fs/readdir.c:67 iterate_dir+0x1c2/0x580 fs/readdir.c:106 __do_sys_getdents64 fs/readdir.c:405 [inline] __se_sys_getdents64+0xe9/0x260 fs/readdir.c:390 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: 0033:0x7f167938f749 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe3016dff8 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007f16795e5fa0 RCX: 00007f167938f749 RDX: 0000000000000099 RSI: 0000200000000400 RDI: 0000000000000005 RBP: 00007f1679413f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f16795e5fa0 R14: 00007f16795e5fa0 R15: 0000000000000003 </TASK> Allocated by task 5930: 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:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc_lru+0x115/0x2e0 mm/slub.c:3526 alloc_inode_sb include/linux/fs.h:2946 [inline] jfs_alloc_inode+0x28/0x60 fs/jfs/super.c:105 alloc_inode fs/inode.c:261 [inline] new_inode_pseudo+0x63/0x1d0 fs/inode.c:1049 new_inode+0x22/0x1b0 fs/inode.c:1075 ialloc+0x4c/0x950 fs/jfs/jfs_inode.c:48 jfs_create+0x18b/0xa40 fs/jfs/namei.c:92 lookup_open fs/namei.c:3496 [inline] open_last_lookups fs/namei.c:3564 [inline] path_openat+0x1277/0x3190 fs/namei.c:3794 do_filp_open+0x1c5/0x3d0 fs/namei.c:3824 do_sys_openat2+0x12c/0x1c0 fs/open.c:1421 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1447 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 ffff88805f930940 which belongs to the cache jfs_ip of size 2240 The buggy address is located 16 bytes to the right of allocated 2240-byte region [ffff88805f930940, ffff88805f931200) The buggy address belongs to the physical page: page:ffffea00017e4c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5f930 head:ffffea00017e4c00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88807c0ebc01 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888018b853c0 dead000000000122 0000000000000000 raw: 0000000000000000 00000000800d000d 00000001ffffffff ffff88807c0ebc01 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d2050(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 5930, tgid 5930 (syz.0.17), ts 105322123817, free_ts 28628187766 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:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2e0 mm/slub.c:2081 ___slab_alloc+0xc6d/0x1300 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc_lru+0x1ae/0x2e0 mm/slub.c:3526 alloc_inode_sb include/linux/fs.h:2946 [inline] jfs_alloc_inode+0x28/0x60 fs/jfs/super.c:105 alloc_inode fs/inode.c:261 [inline] iget_locked+0x1ad/0x840 fs/inode.c:1359 jfs_iget+0x24/0x440 fs/jfs/inode.c:29 jfs_fill_super+0x70c/0xac0 fs/jfs/super.c:580 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:3386 do_mount fs/namespace.c:3726 [inline] __do_sys_mount fs/namespace.c:3935 [inline] __se_sys_mount+0x2da/0x3c0 fs/namespace.c:3912 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 free_contig_range+0xa1/0x160 mm/page_alloc.c:6369 destroy_args+0x80/0x850 mm/debug_vm_pgtable.c:1015 debug_vm_pgtable+0x3cc/0x410 mm/debug_vm_pgtable.c:1400 do_one_initcall+0x1fd/0x750 init/main.c:1250 do_initcall_level+0x137/0x1f0 init/main.c:1312 do_initcalls+0x69/0xd0 init/main.c:1328 kernel_init_freeable+0x3d2/0x570 init/main.c:1565 kernel_init+0x1d/0x1c0 init/main.c:1455 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Memory state around the buggy address: ffff88805f931100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88805f931180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88805f931200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88805f931280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805f931300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================

Crashes (1):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2025/12/25 14:41	linux-6.6.y	5fa4793a2d2d	d6526ea3	.config	console log	report	syz / log	C		[disk image] [vmlinux] [kernel image] [mounted in repro (corrupt fs)]	ci2-linux-6-6-kasan	KASAN: slab-out-of-bounds Read in dtReadFirst

Crashes (1):

Assets (help?)