================================================================== BUG: KASAN: use-after-free in ocfs2_find_victim_chain fs/ocfs2/suballoc.c:1445 [inline] BUG: KASAN: use-after-free in ocfs2_claim_suballoc_bits+0x10d3/0x2560 fs/ocfs2/suballoc.c:1982 Read of size 4 at addr ffff88807a8ac000 by task syz.7.120/7063 CPU: 0 UID: 0 PID: 7063 Comm: syz.7.120 Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x169/0x550 mm/kasan/report.c:489 kasan_report+0x143/0x180 mm/kasan/report.c:602 ocfs2_find_victim_chain fs/ocfs2/suballoc.c:1445 [inline] ocfs2_claim_suballoc_bits+0x10d3/0x2560 fs/ocfs2/suballoc.c:1982 ocfs2_claim_metadata+0x16d/0x580 fs/ocfs2/suballoc.c:2057 ocfs2_dx_dir_attach_index+0x231/0xf90 fs/ocfs2/dir.c:2308 ocfs2_expand_inline_dir fs/ocfs2/dir.c:3000 [inline] ocfs2_extend_dir+0x439f/0x53c0 fs/ocfs2/dir.c:3182 ocfs2_prepare_dir_for_insert+0x33b5/0x5c40 fs/ocfs2/dir.c:4287 ocfs2_mknod+0xcaf/0x2b30 fs/ocfs2/namei.c:294 ocfs2_mkdir+0x1ab/0x470 fs/ocfs2/namei.c:657 vfs_mkdir+0x2f9/0x4f0 fs/namei.c:4311 do_mkdirat+0x264/0x3a0 fs/namei.c:4334 __do_sys_mkdirat fs/namei.c:4349 [inline] __se_sys_mkdirat fs/namei.c:4347 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4347 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f35e3f7e787 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:00007f35e4e16e88 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007f35e4e16f10 RCX: 00007f35e3f7e787 RDX: 00000000000001ff RSI: 0000000020000680 RDI: 00000000ffffff9c RBP: 0000000020000080 R08: 0000000020000100 R09: 0000000000000000 R10: 0000000020000080 R11: 0000000000000246 R12: 0000000020000680 R13: 00007f35e4e16ed0 R14: 0000000000000000 R15: 0000000000000000 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:ffff88807e069dc0 index:0x95d pfn:0x7a8ac memcg:ffff888065f26000 aops:shmem_aops ino:88 dentry name(?):"memfd:syzkaller" flags: 0xfff0000002003c(referenced|uptodate|dirty|lru|swapbacked|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff0000002003c ffffea000153ffc8 ffffea0001ea2b48 ffff88807e069dc0 raw: 000000000000095d 0000000000000000 00000001ffffffff ffff888065f26000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Movable, gfp_mask 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 7111, tgid 7110 (syz.6.123), ts 124912978636, free_ts 124540336072 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556 prep_new_page mm/page_alloc.c:1564 [inline] get_page_from_freelist+0x3651/0x37a0 mm/page_alloc.c:3474 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2269 folio_alloc_mpol_noprof+0x36/0x50 mm/mempolicy.c:2287 shmem_alloc_folio mm/shmem.c:1794 [inline] shmem_alloc_and_add_folio+0x4a0/0x1080 mm/shmem.c:1833 shmem_get_folio_gfp+0x621/0x1840 mm/shmem.c:2355 shmem_get_folio mm/shmem.c:2461 [inline] shmem_write_begin+0x165/0x350 mm/shmem.c:3117 generic_perform_write+0x346/0x990 mm/filemap.c:4055 shmem_file_write_iter+0xf9/0x120 mm/shmem.c:3293 new_sync_write fs/read_write.c:586 [inline] vfs_write+0xaeb/0xd30 fs/read_write.c:679 ksys_write+0x18f/0x2b0 fs/read_write.c:731 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 7063 tgid 7062 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1127 [inline] free_unref_folios+0xe23/0x1890 mm/page_alloc.c:2704 folios_put_refs+0x76c/0x860 mm/swap.c:962 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x593/0x1820 mm/shmem.c:1040 shmem_truncate_range mm/shmem.c:1152 [inline] shmem_evict_inode+0x29b/0xa80 mm/shmem.c:1280 evict+0x4e8/0x9a0 fs/inode.c:796 __dentry_kill+0x20d/0x630 fs/dcache.c:625 dput+0x19f/0x2b0 fs/dcache.c:867 __fput+0x5ba/0xa50 fs/file_table.c:458 __do_sys_close fs/open.c:1554 [inline] __se_sys_close fs/open.c:1539 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1539 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88807a8abf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88807a8abf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88807a8ac000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff88807a8ac080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88807a8ac100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================