================================================================== BUG: KASAN: slab-out-of-bounds in dtSplitPage+0x12c6/0x3b20 fs/jfs/jfs_dtree.c:-1 Read of size 1 at addr ffff8880518788d5 by task syz.2.461/10011 CPU: 0 UID: 0 PID: 10011 Comm: syz.2.461 Not tainted 6.15.0-rc5-syzkaller-00275-gbec6f00f120e #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xb4/0x290 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 dtSplitPage+0x12c6/0x3b20 fs/jfs/jfs_dtree.c:-1 dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline] dtInsert+0x109b/0x5f40 fs/jfs/jfs_dtree.c:871 jfs_create+0x6c8/0xa80 fs/jfs/namei.c:137 lookup_open fs/namei.c:3701 [inline] open_last_lookups fs/namei.c:3800 [inline] path_openat+0x14f1/0x3830 fs/namei.c:4036 do_filp_open+0x1fa/0x410 fs/namei.c:4066 do_sys_openat2+0x121/0x1c0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_openat fs/open.c:1460 [inline] __se_sys_openat fs/open.c:1455 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1455 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe5abf8e969 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:00007fe5ace4e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fe5ac1b6240 RCX: 00007fe5abf8e969 RDX: 000000000000275a RSI: 0000200000000280 RDI: ffffffffffffff9c RBP: 00007fe5ac010ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fe5ac1b6240 R15: 00007ffe81717678 Allocated by task 9959: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4147 [inline] slab_alloc_node mm/slub.c:4196 [inline] kmem_cache_alloc_lru_noprof+0x1c6/0x3d0 mm/slub.c:4215 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105 alloc_inode+0x67/0x1b0 fs/inode.c:346 iget_locked+0xf0/0x570 fs/inode.c:1439 jfs_iget+0x24/0x3e0 fs/jfs/inode.c:29 jfs_lookup+0x1c5/0x380 fs/jfs/namei.c:1469 __lookup_slow+0x294/0x3d0 fs/namei.c:1817 lookup_slow+0x53/0x70 fs/namei.c:1834 walk_component+0x2d2/0x400 fs/namei.c:2138 lookup_last fs/namei.c:2636 [inline] path_lookupat+0x163/0x430 fs/namei.c:2660 filename_lookup+0x212/0x570 fs/namei.c:2689 user_path_at+0x3a/0x60 fs/namei.c:3120 __do_sys_chdir fs/open.c:557 [inline] __se_sys_chdir+0x91/0x280 fs/open.c:551 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888051878000 which belongs to the cache jfs_ip of size 2232 The buggy address is located 29 bytes to the right of allocated 2232-byte region [ffff888051878000, ffff8880518788b8) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888051879ba8 pfn:0x51878 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888029d89501 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801e374c80 dead000000000122 0000000000000000 raw: ffff888051879ba8 00000000800d000b 00000000f5000000 ffff888029d89501 head: 00fff00000000040 ffff88801e374c80 dead000000000122 0000000000000000 head: ffff888051879ba8 00000000800d000b 00000000f5000000 ffff888029d89501 head: 00fff00000000003 ffffea0001461e01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Reclaimable, gfp_mask 0xd2050(__GFP_RECLAIMABLE|__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6185, tgid 6184 (syz.1.28), ts 114948137588, free_ts 112610490713 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1d8/0x230 mm/page_alloc.c:1718 prep_new_page mm/page_alloc.c:1726 [inline] get_page_from_freelist+0x21c7/0x22a0 mm/page_alloc.c:3688 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4970 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2450 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2618 new_slab mm/slub.c:2672 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3858 __slab_alloc mm/slub.c:3948 [inline] __slab_alloc_node mm/slub.c:4023 [inline] slab_alloc_node mm/slub.c:4184 [inline] kmem_cache_alloc_lru_noprof+0x288/0x3d0 mm/slub.c:4215 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105 alloc_inode+0x67/0x1b0 fs/inode.c:346 new_inode+0x22/0x170 fs/inode.c:1145 jfs_fill_super+0x569/0xd90 fs/jfs/super.c:511 get_tree_bdev_flags+0x40b/0x4d0 fs/super.c:1636 vfs_get_tree+0x8f/0x2b0 fs/super.c:1759 do_new_mount+0x24a/0xa40 fs/namespace.c:3881 do_mount fs/namespace.c:4221 [inline] __do_sys_mount fs/namespace.c:4432 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4409 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 page last free pid 5823 tgid 5823 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_pages_ok+0x910/0xac0 mm/page_alloc.c:1438 __folio_put+0x21b/0x2c0 mm/swap.c:112 folio_put include/linux/mm.h:1580 [inline] free_large_kmalloc+0x145/0x200 mm/slub.c:4767 __btree_node_data_free+0x2fe/0x5d0 fs/bcachefs/btree_cache.c:113 btree_node_data_free fs/bcachefs/btree_cache.c:130 [inline] bch2_fs_btree_cache_exit+0xac2/0x14c0 fs/bcachefs/btree_cache.c:612 __bch2_fs_free fs/bcachefs/super.c:563 [inline] bch2_fs_release+0x238/0x7f0 fs/bcachefs/super.c:618 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x228/0x480 lib/kobject.c:737 deactivate_locked_super+0xb9/0x130 fs/super.c:473 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1431 task_work_run+0x1d1/0x260 kernel/task_work.c:227 resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50 exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888051878780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888051878800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888051878880: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ^ ffff888051878900: fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb fb ffff888051878980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================