================================================================== BUG: KASAN: slab-use-after-free in check_igot_inode fs/ext4/inode.c:-1 [inline] BUG: KASAN: slab-use-after-free in __ext4_iget+0x2bd/0x3e70 fs/ext4/inode.c:4832 Read of size 8 at addr ffff888074c38c70 by task syz.1.4176/14934 CPU: 1 PID: 14934 Comm: syz.1.4176 Not tainted 6.6.102-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 check_igot_inode fs/ext4/inode.c:-1 [inline] __ext4_iget+0x2bd/0x3e70 fs/ext4/inode.c:4832 __ext4_fill_super fs/ext4/super.c:5502 [inline] ext4_fill_super+0x4a79/0x6620 fs/ext4/super.c:5729 get_tree_bdev+0x3e4/0x510 fs/super.c:1591 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24b/0xa40 fs/namespace.c:3371 do_mount fs/namespace.c:3711 [inline] __do_sys_mount fs/namespace.c:3920 [inline] __se_sys_mount+0x2da/0x3c0 fs/namespace.c:3897 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: 0033:0x7fc568d9038a Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 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:00007fc569c34e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fc569c34ef0 RCX: 00007fc568d9038a RDX: 0000200000000080 RSI: 0000200000000540 RDI: 00007fc569c34eb0 RBP: 0000200000000080 R08: 00007fc569c34ef0 R09: 000000000000808d R10: 000000000000808d R11: 0000000000000246 R12: 0000200000000540 R13: 00007fc569c34eb0 R14: 0000000000000504 R15: 00002000000000c0 Allocated by task 6481: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3485 [inline] slab_alloc mm/slub.c:3493 [inline] __kmem_cache_alloc_lru mm/slub.c:3500 [inline] kmem_cache_alloc_lru+0x115/0x2e0 mm/slub.c:3516 alloc_inode_sb include/linux/fs.h:2946 [inline] reiserfs_alloc_inode+0x2a/0xc0 fs/reiserfs/super.c:642 alloc_inode fs/inode.c:261 [inline] new_inode_pseudo+0x63/0x1d0 fs/inode.c:1049 new_inode+0x22/0x1b0 fs/inode.c:1075 reiserfs_mkdir+0x189/0x970 fs/reiserfs/namei.c:813 xattr_mkdir fs/reiserfs/xattr.c:77 [inline] create_privroot fs/reiserfs/xattr.c:891 [inline] reiserfs_xattr_init+0x33c/0x6a0 fs/reiserfs/xattr.c:1007 reiserfs_fill_super+0x1f85/0x2340 fs/reiserfs/super.c:2175 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:3371 do_mount fs/namespace.c:3711 [inline] __do_sys_mount fs/namespace.c:3920 [inline] __se_sys_mount+0x2da/0x3c0 fs/namespace.c:3897 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 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x158/0x930 kernel/rcu/tree.c:2837 destroy_inode fs/inode.c:316 [inline] evict+0x7db/0x870 fs/inode.c:720 dispose_list fs/inode.c:738 [inline] evict_inodes+0x5fe/0x690 fs/inode.c:792 generic_shutdown_super+0x97/0x2b0 fs/super.c:672 kill_block_super+0x44/0x90 fs/super.c:1660 deactivate_locked_super+0x97/0x100 fs/super.c:481 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250 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+0xb1/0x140 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 The buggy address belongs to the object at ffff888074c386a0 which belongs to the cache reiser_inode_cache of size 1568 The buggy address is located 1488 bytes inside of freed 1568-byte region [ffff888074c386a0, ffff888074c38cc0) The buggy address belongs to the physical page: page:ffffea0001d30e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888074c3a7c0 pfn:0x74c38 head:ffffea0001d30e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888023457601 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff8880186d1c80 dead000000000122 0000000000000000 raw: ffff888074c3a7c0 000000008013000c 00000001ffffffff ffff888023457601 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 6481, tgid 6480 (syz.2.535), ts 81489760754, free_ts 81011774295 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 alloc_slab_page+0x5d/0x170 mm/slub.c:1876 allocate_slab mm/slub.c:2023 [inline] new_slab+0x87/0x2e0 mm/slub.c:2076 ___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230 __slab_alloc mm/slub.c:3329 [inline] __slab_alloc_node mm/slub.c:3382 [inline] slab_alloc_node mm/slub.c:3475 [inline] slab_alloc mm/slub.c:3493 [inline] __kmem_cache_alloc_lru mm/slub.c:3500 [inline] kmem_cache_alloc_lru+0x1ae/0x2e0 mm/slub.c:3516 alloc_inode_sb include/linux/fs.h:2946 [inline] reiserfs_alloc_inode+0x2a/0xc0 fs/reiserfs/super.c:642 alloc_inode fs/inode.c:261 [inline] iget5_locked+0xa2/0x260 fs/inode.c:1314 reiserfs_fill_super+0x1170/0x2340 fs/reiserfs/super.c:2053 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:3371 do_mount fs/namespace.c:3711 [inline] __do_sys_mount fs/namespace.c:3920 [inline] __se_sys_mount+0x2da/0x3c0 fs/namespace.c:3897 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+0x32/0x2e0 mm/page_alloc.c:2429 __slab_free+0x35e/0x410 mm/slub.c:3722 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x13e/0x260 mm/slub.c:3524 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x240 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x20f/0x4b0 security/tomoyo/file.c:822 security_inode_getattr+0xd3/0x120 security/security.c:2153 vfs_getattr fs/stat.c:173 [inline] vfs_fstat fs/stat.c:198 [inline] __do_sys_newfstat fs/stat.c:473 [inline] __se_sys_newfstat fs/stat.c:470 [inline] __x64_sys_newfstat+0x101/0x1f0 fs/stat.c:470 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: ffff888074c38b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888074c38b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888074c38c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888074c38c80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888074c38d00: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ==================================================================