ocfs2: Mounting device (7,3) on (node local, slot 0) with ordered data mode. ================================================================== BUG: KASAN: use-after-free in ocfs2_find_victim_chain fs/ocfs2/suballoc.c:1447 [inline] BUG: KASAN: use-after-free in ocfs2_claim_suballoc_bits+0x8b2/0x2450 fs/ocfs2/suballoc.c:1996 Read of size 4 at addr ffff88806cd20000 by task syz.3.171/6910 CPU: 0 UID: 0 PID: 6910 Comm: syz.3.171 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 ocfs2_find_victim_chain fs/ocfs2/suballoc.c:1447 [inline] ocfs2_claim_suballoc_bits+0x8b2/0x2450 fs/ocfs2/suballoc.c:1996 __ocfs2_claim_clusters+0x303/0x8f0 fs/ocfs2/suballoc.c:2421 ocfs2_claim_clusters fs/ocfs2/suballoc.c:2458 [inline] ocfs2_block_group_alloc_contig fs/ocfs2/suballoc.c:432 [inline] ocfs2_block_group_alloc fs/ocfs2/suballoc.c:699 [inline] ocfs2_reserve_suballoc_bits+0xf1e/0x4640 fs/ocfs2/suballoc.c:834 ocfs2_reserve_new_metadata_blocks+0x403/0x940 fs/ocfs2/suballoc.c:984 ocfs2_expand_inline_dir fs/ocfs2/dir.c:2845 [inline] ocfs2_extend_dir+0xc76/0x4870 fs/ocfs2/dir.c:3207 ocfs2_prepare_dir_for_insert+0x2fe8/0x5450 fs/ocfs2/dir.c:4312 ocfs2_mknod+0x819/0x2050 fs/ocfs2/namei.c:297 ocfs2_mkdir+0x191/0x440 fs/ocfs2/namei.c:659 vfs_mkdir+0x303/0x510 fs/namei.c:4366 do_mkdirat+0x247/0x590 fs/namei.c:4399 __do_sys_mkdirat fs/namei.c:4416 [inline] __se_sys_mkdirat fs/namei.c:4414 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4414 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdb2f78d457 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 02 01 00 00 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:00007fdb306c9e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007fdb306c9ef0 RCX: 00007fdb2f78d457 RDX: 00000000000001ff RSI: 0000200000000680 RDI: 00000000ffffff9c RBP: 0000200000000080 R08: 0000200000000140 R09: 0000000000000000 R10: 0000200000000080 R11: 0000000000000246 R12: 0000200000000680 R13: 00007fdb306c9eb0 R14: 0000000000000000 R15: 0000000000000000 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x5e7 pfn:0x6cd20 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f0(buddy) raw: 00fff00000000000 ffffea0001309808 ffffea0001327008 0000000000000000 raw: 00000000000005e7 0000000000000005 00000000f0000000 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 6798, tgid 6796 (syz.0.156), ts 160022482607, free_ts 161018972282 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3863 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5153 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416 folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2435 shmem_alloc_folio mm/shmem.c:1908 [inline] shmem_alloc_and_add_folio+0x447/0xf60 mm/shmem.c:1947 shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2596 shmem_fault+0x179/0x390 mm/shmem.c:2797 __do_fault+0x135/0x390 mm/memory.c:5280 do_read_fault mm/memory.c:5703 [inline] do_fault mm/memory.c:5837 [inline] do_pte_missing mm/memory.c:4362 [inline] handle_pte_fault mm/memory.c:6182 [inline] __handle_mm_fault+0x35e3/0x5400 mm/memory.c:6323 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6492 faultin_page mm/gup.c:1136 [inline] __get_user_pages+0x1699/0x2ce0 mm/gup.c:1438 populate_vma_page_range+0x29f/0x3a0 mm/gup.c:1872 __mm_populate+0x24c/0x380 mm/gup.c:1975 mm_populate include/linux/mm.h:3455 [inline] vm_mmap_pgoff+0x387/0x4d0 mm/util.c:585 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 page last free pid 6796 tgid 6796 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] free_unref_folios+0xdb3/0x14f0 mm/page_alloc.c:2957 folios_put_refs+0x584/0x670 mm/swap.c:1002 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x49e/0x14b0 mm/shmem.c:1157 shmem_truncate_range mm/shmem.c:1269 [inline] shmem_evict_inode+0x272/0xa70 mm/shmem.c:1397 evict+0x501/0x9c0 fs/inode.c:810 __dentry_kill+0x209/0x660 fs/dcache.c:669 dput+0x19f/0x2b0 fs/dcache.c:911 __fput+0x68e/0xa70 fs/file_table.c:476 task_work_run+0x1d1/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x6b5/0x2300 kernel/exit.c:966 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107 __do_sys_exit_group kernel/exit.c:1118 [inline] __se_sys_exit_group kernel/exit.c:1116 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1116 x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88806cd1ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88806cd1ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88806cd20000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88806cd20080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88806cd20100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================