loop2: detected capacity change from 0 to 32768 ocfs2: Mounting device (7,2) on (node local, slot 0) with ordered data mode. ================================================================== BUG: KASAN: use-after-free in ocfs2_find_victim_chain fs/ocfs2/suballoc.c:1391 [inline] BUG: KASAN: use-after-free in ocfs2_claim_suballoc_bits+0xeb0/0x2230 fs/ocfs2/suballoc.c:1927 Read of size 4 at addr ffff88805836e000 by task syz.2.1611/12219 CPU: 1 PID: 12219 Comm: syz.2.1611 Not tainted 6.6.101-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: 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 ocfs2_find_victim_chain fs/ocfs2/suballoc.c:1391 [inline] ocfs2_claim_suballoc_bits+0xeb0/0x2230 fs/ocfs2/suballoc.c:1927 ocfs2_claim_new_inode+0x32a/0x780 fs/ocfs2/suballoc.c:2210 ocfs2_mknod_locked+0x101/0x250 fs/ocfs2/namei.c:635 ocfs2_mknod+0x107e/0x20f0 fs/ocfs2/namei.c:381 ocfs2_create+0x196/0x410 fs/ocfs2/namei.c:674 lookup_open fs/namei.c:3488 [inline] open_last_lookups fs/namei.c:3556 [inline] path_openat+0x1277/0x3190 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: 0033:0x7fbe78b8eb69 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:00007fbe799e0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007fbe78db5fa0 RCX: 00007fbe78b8eb69 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000d80 RBP: 00007fbe78c11df1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fbe78db5fa0 R15: 00007ffd932b07d8 The buggy address belongs to the physical page: page:ffffea000160db80 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x5836e flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000000 ffffea000160dbc8 ffffea0001555c48 0000000000000000 raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Movable, gfp_mask 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 12196, tgid 12156 (syz.5.1595), ts 651702874283, free_ts 654247976960 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 __folio_alloc+0x10/0x20 mm/page_alloc.c:4489 vma_alloc_folio+0x47a/0x8f0 mm/mempolicy.c:2242 shmem_alloc_folio+0x179/0x230 mm/shmem.c:1680 shmem_alloc_and_acct_folio+0x189/0x630 mm/shmem.c:1705 shmem_get_folio_gfp+0xcde/0x2ac0 mm/shmem.c:2042 shmem_fault+0x1b6/0x7f0 mm/shmem.c:2249 __do_fault+0x13b/0x4e0 mm/memory.c:4243 do_read_fault mm/memory.c:4616 [inline] do_fault mm/memory.c:4753 [inline] do_pte_missing mm/memory.c:3688 [inline] handle_pte_fault mm/memory.c:5025 [inline] __handle_mm_fault mm/memory.c:5166 [inline] handle_mm_fault+0x3886/0x4920 mm/memory.c:5331 faultin_page mm/gup.c:868 [inline] __get_user_pages+0x5ea/0x1470 mm/gup.c:1167 populate_vma_page_range+0x2b6/0x370 mm/gup.c:1593 __mm_populate+0x24c/0x380 mm/gup.c:1696 mm_populate include/linux/mm.h:3317 [inline] vm_mmap_pgoff+0x2e7/0x400 mm/util.c:561 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 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_list+0xbe/0x860 mm/page_alloc.c:2475 release_pages+0x1fa0/0x2220 mm/swap.c:1022 __folio_batch_release+0x71/0xe0 mm/swap.c:1042 folio_batch_release include/linux/pagevec.h:83 [inline] shmem_undo_range+0x5d0/0x1a40 mm/shmem.c:1027 shmem_truncate_range mm/shmem.c:1136 [inline] shmem_evict_inode+0x273/0xa70 mm/shmem.c:1265 evict+0x486/0x870 fs/inode.c:705 __dentry_kill+0x431/0x650 fs/dcache.c:611 dentry_kill+0xb8/0x290 fs/dcache.c:-1 dput+0xfe/0x1e0 fs/dcache.c:918 __fput+0x5e5/0x970 fs/file_table.c:392 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 Memory state around the buggy address: ffff88805836df00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88805836df80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88805836e000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88805836e080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805836e100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================