syzbot

syz.0.17[5945]: memfd_create() called without MFD_EXEC or MFD_NOEXEC_SEAL set
loop0: detected capacity change from 0 to 32768
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BUG: KASAN: slab-out-of-bounds in dtCompare fs/jfs/jfs_dtree.c:3333 [inline]
BUG: KASAN: slab-out-of-bounds in dtSearch+0x167a/0x21b0 fs/jfs/jfs_dtree.c:650
Read of size 1 at addr ffff888061c6b718 by task syz.0.17/5945

CPU: 0 PID: 5945 Comm: syz.0.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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
 dtCompare fs/jfs/jfs_dtree.c:3333 [inline]
 dtSearch+0x167a/0x21b0 fs/jfs/jfs_dtree.c:650
 jfs_lookup+0x156/0x380 fs/jfs/namei.c:1459
 lookup_open fs/namei.c:3466 [inline]
 open_last_lookups fs/namei.c:3556 [inline]
 path_openat+0x10b8/0x3190 fs/namei.c:3786
 do_filp_open+0x1c5/0x3d0 fs/namei.c:3816
 do_sys_openat2+0x12c/0x1c0 fs/open.c:1419
 do_sys_open fs/open.c:1434 [inline]
 __do_sys_creat fs/open.c:1512 [inline]
 __se_sys_creat fs/open.c:1506 [inline]
 __x64_sys_creat+0x90/0xb0 fs/open.c:1506
 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: 0033:0x7f94f058eba9
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:00007ffc7eb39c48 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007f94f07d5fa0 RCX: 00007f94f058eba9
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000200000000100
RBP: 00007f94f0611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f94f07d5fa0 R14: 00007f94f07d5fa0 R15: 0000000000000002
 </TASK>

The buggy address belongs to the object at ffff888061c6ae40
 which belongs to the cache jfs_ip of size 2240
The buggy address is located 24 bytes to the right of
 allocated 2240-byte region [ffff888061c6ae40, ffff888061c6b700)

The buggy address belongs to the physical page:
page:ffffea0001871a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x61c68
head:ffffea0001871a00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff88802dc12401
flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888143295b40 dead000000000122 0000000000000000
raw: 0000000000000000 00000000800d000d 00000001ffffffff ffff88802dc12401
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 5945, tgid 5945 (syz.0.17), ts 93684622718, free_ts 86103466813
 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]
 new_inode_pseudo+0x63/0x1d0 fs/inode.c:1049
 new_inode+0x22/0x1b0 fs/inode.c:1075
 diReadSpecial+0x52/0x710 fs/jfs/jfs_imap.c:426
 jfs_mount+0x73/0x860 fs/jfs/jfs_mount.c:87
 jfs_fill_super+0x4e2/0xac0 fs/jfs/super.c:556
 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
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
 vfree+0x1a6/0x320 mm/vmalloc.c:2868
 kcov_put kernel/kcov.c:438 [inline]
 kcov_close+0x2b/0x50 kernel/kcov.c:534
 __fput+0x234/0x970 fs/file_table.c:384
 task_work_run+0x1ce/0x250 kernel/task_work.c:239
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0x90b/0x23c0 kernel/exit.c:883
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024
 get_signal+0x12fc/0x1400 kernel/signal.c:2902
 arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff888061c6b600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888061c6b680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888061c6b700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                            ^
 ffff888061c6b780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888061c6b800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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