loop0: detected capacity change from 0 to 512 ================================================================== BUG: KASAN: use-after-free in check_igot_inode fs/ext4/inode.c:-1 [inline] BUG: KASAN: use-after-free in __ext4_iget+0x2bb/0x3e40 fs/ext4/inode.c:4867 Read of size 8 at addr ffff88806896bad0 by task syz.0.10636/28648 CPU: 0 PID: 28648 Comm: syz.0.10636 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 check_igot_inode fs/ext4/inode.c:-1 [inline] __ext4_iget+0x2bb/0x3e40 fs/ext4/inode.c:4867 __ext4_fill_super fs/ext4/super.c:5423 [inline] ext4_fill_super+0x60c1/0x7dc0 fs/ext4/super.c:5687 get_tree_bdev+0x3f1/0x610 fs/super.c:1366 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd24fb9c14a Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd250a05e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fd250a05ee0 RCX: 00007fd24fb9c14a RDX: 00002000000004c0 RSI: 00002000000008c0 RDI: 00007fd250a05ea0 RBP: 00002000000004c0 R08: 00007fd250a05ee0 R09: 0000000001008490 R10: 0000000001008490 R11: 0000000000000246 R12: 00002000000008c0 R13: 00007fd250a05ea0 R14: 00000000000004eb R15: 0000200000000a40 Allocated by task 16802: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc_lru+0x11a/0x2e0 mm/slub.c:3390 alloc_inode_sb include/linux/fs.h:3245 [inline] reiserfs_alloc_inode+0x26/0xc0 fs/reiserfs/super.c:642 alloc_inode fs/inode.c:261 [inline] iget5_locked+0x9e/0x260 fs/inode.c:1328 reiserfs_fill_super+0x11d3/0x23b0 fs/reiserfs/super.c:2053 mount_bdev+0x287/0x3c0 fs/super.c:1443 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 call_rcu+0x14f/0x990 kernel/rcu/tree.c:2849 destroy_inode fs/inode.c:316 [inline] evict+0x834/0x8d0 fs/inode.c:720 reiserfs_fill_super+0x1475/0x23b0 fs/reiserfs/super.c:2078 mount_bdev+0x287/0x3c0 fs/super.c:1443 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Second to last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 call_rcu+0x14f/0x990 kernel/rcu/tree.c:2849 destroy_inode fs/inode.c:316 [inline] evict+0x834/0x8d0 fs/inode.c:720 reiserfs_fill_super+0x1475/0x23b0 fs/reiserfs/super.c:2078 mount_bdev+0x287/0x3c0 fs/super.c:1443 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88806896b500 which belongs to the cache reiser_inode_cache of size 1568 The buggy address is located 1488 bytes inside of 1568-byte region [ffff88806896b500, ffff88806896bb20) The buggy address belongs to the physical page: page:ffffea0001a25a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88806896ea00 pfn:0x68968 head:ffffea0001a25a00 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff88802f1eaa01 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff8880185c5280 raw: ffff88806896ea00 0000000080130006 00000001ffffffff ffff88802f1eaa01 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 4901, tgid 4900 (syz.2.231), ts 84686893676, free_ts 82987177949 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4328 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5614 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc_lru+0x1ae/0x2e0 mm/slub.c:3390 alloc_inode_sb include/linux/fs.h:3245 [inline] reiserfs_alloc_inode+0x26/0xc0 fs/reiserfs/super.c:642 alloc_inode fs/inode.c:261 [inline] iget5_locked+0x9e/0x260 fs/inode.c:1328 reiserfs_fill_super+0x11d3/0x23b0 fs/reiserfs/super.c:2053 mount_bdev+0x287/0x3c0 fs/super.c:1443 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare mm/page_alloc.c:1509 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383 getname_flags+0xb7/0x500 fs/namei.c:139 getname fs/namei.c:218 [inline] __do_sys_unlink fs/namei.c:4446 [inline] __se_sys_unlink fs/namei.c:4444 [inline] __x64_sys_unlink+0x38/0x50 fs/namei.c:4444 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88806896b980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806896ba00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88806896ba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806896bb00: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ffff88806896bb80: fc fc fc fc 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================