================================================================== BUG: KASAN: use-after-free in reiserfs_release_objectid+0x575/0x820 fs/reiserfs/objectid.c:165 Read of size 8188 at addr ffff88804f9cb050 by task syz.4.68/6436 CPU: 0 PID: 6436 Comm: syz.4.68 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x288/0x290 mm/kasan/generic.c:187 __asan_memmove+0x29/0x70 mm/kasan/shadow.c:94 reiserfs_release_objectid+0x575/0x820 fs/reiserfs/objectid.c:165 remove_save_link+0x2ba/0x3c0 fs/reiserfs/super.c:542 reiserfs_evict_inode+0x395/0x490 fs/reiserfs/inode.c:91 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 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 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 RIP: 0033:0x7fb37af8f749 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:00007ffc8e57cd48 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007fb37b1e7da0 RCX: 00007fb37af8f749 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007fb37b1e7da0 R08: 0000000000000208 R09: 0000001e8e57d03f R10: 00007fb37b1e7cb0 R11: 0000000000000246 R12: 0000000000021c81 R13: 00007fb37b1e6180 R14: ffffffffffffffff R15: 00007ffc8e57ce60 The buggy address belongs to the physical page: page:ffffea00013e72c0 refcount:2 mapcount:0 mapping:ffff88801fd17b78 index:0x10 pfn:0x4f9cb memcg:ffff88805f44a000 aops:def_blk_aops ino:700004 flags: 0xfff5800002822c(referenced|uptodate|lru|workingset|private|mappedtodisk|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff5800002822c ffffea00016a7d48 ffffea000163d748 ffff88801fd17b78 raw: 0000000000000010 ffff88805143b488 00000002ffffffff ffff88805f44a000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Movable, gfp_mask 0x148c48(GFP_NOFS|__GFP_NOFAIL|__GFP_COMP|__GFP_HARDWALL|__GFP_MOVABLE), pid 6437, tgid 6436 (syz.4.68), ts 136217912025, free_ts 136075993445 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+0x1e/0x30 mm/mempolicy.c:2291 filemap_alloc_folio+0xdf/0x470 mm/filemap.c:1004 __filemap_get_folio+0x3ee/0xbc0 mm/filemap.c:1962 grow_dev_page fs/buffer.c:1058 [inline] grow_buffers fs/buffer.c:1118 [inline] __getblk_slow fs/buffer.c:1145 [inline] __getblk_gfp+0x223/0x660 fs/buffer.c:1439 __bread_gfp+0x2a/0x330 fs/buffer.c:1473 sb_bread include/linux/buffer_head.h:326 [inline] read_super_block+0x91/0x7c0 fs/reiserfs/super.c:1604 reiserfs_fill_super+0x7a2/0x2340 fs/reiserfs/super.c:1966 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 do_new_mount+0x24b/0xa40 fs/namespace.c:3386 do_mount fs/namespace.c:3726 [inline] __do_sys_mount fs/namespace.c:3935 [inline] __se_sys_mount+0x2da/0x3c0 fs/namespace.c:3912 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 tlb_batch_pages_flush mm/mmu_gather.c:98 [inline] tlb_flush_mmu_free mm/mmu_gather.c:293 [inline] tlb_flush_mmu+0x368/0x4f0 mm/mmu_gather.c:300 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:392 exit_mmap+0x3f0/0xb50 mm/mmap.c:3315 __mmput+0x118/0x3c0 kernel/fork.c:1355 exit_mm+0x1da/0x2c0 kernel/exit.c:569 do_exit+0x88e/0x23c0 kernel/exit.c:870 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 __do_sys_exit_group kernel/exit.c:1035 [inline] __se_sys_exit_group kernel/exit.c:1033 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1033 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 Memory state around the buggy address: ffff88804f9cbf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88804f9cbf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88804f9cc000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88804f9cc080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88804f9cc100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================