================================================================== BUG: KASAN: use-after-free in ext4_xattr_delete_inode+0xc94/0xca0 fs/ext4/xattr.c:2895 Read of size 4 at addr ffff88811cb4e000 by task syz-executor/440 CPU: 0 PID: 440 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:88 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106 print_address_description+0x71/0x200 mm/kasan/report.c:316 print_report+0x4a/0x60 mm/kasan/report.c:420 kasan_report+0x122/0x150 mm/kasan/report.c:524 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:350 ext4_xattr_delete_inode+0xc94/0xca0 fs/ext4/xattr.c:2895 ext4_evict_inode+0xe64/0x1470 fs/ext4/inode.c:296 evict+0x4d7/0x8f0 fs/inode.c:708 iput_final fs/inode.c:1844 [inline] iput+0x620/0x670 fs/inode.c:1870 d_delete_notify include/linux/fsnotify.h:292 [inline] vfs_rmdir+0x3bf/0x500 fs/namei.c:4211 do_rmdir+0x261/0x6b0 fs/namei.c:4259 __do_sys_unlinkat fs/namei.c:4439 [inline] __se_sys_unlinkat fs/namei.c:4433 [inline] __x64_sys_unlinkat+0xc7/0xf0 fs/namei.c:4433 x64_sys_call+0x79f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:264 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: 0033:0x7efd9cf83bc7 Code: 77 01 c3 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 b8 07 01 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:00007ffeef2c8708 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007efd9cf83bc7 RDX: 0000000000000200 RSI: 00007ffeef2c98b0 RDI: 00000000ffffff9c RBP: 00007efd9d001fd2 R08: 0000000000008680 R09: 00000000ffffffff R10: 0000000000000100 R11: 0000000000000207 R12: 00007ffeef2c98b0 R13: 00007efd9d001fd2 R14: 000000000000ac1e R15: 00007ffeef2cba60 Allocated by task 103: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505 __kasan_slab_alloc+0x72/0x80 mm/kasan/common.c:334 kasan_slab_alloc include/linux/kasan.h:202 [inline] slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768 slab_alloc_node mm/slub.c:3382 [inline] slab_alloc mm/slub.c:3392 [inline] __kmem_cache_alloc_lru mm/slub.c:3399 [inline] kmem_cache_alloc+0x16e/0x330 mm/slub.c:3408 kmem_cache_zalloc include/linux/slab.h:689 [inline] lsm_file_alloc security/security.c:575 [inline] security_file_alloc+0x33/0x130 security/security.c:1543 __alloc_file+0xb5/0x2a0 fs/file_table.c:143 alloc_empty_file+0x97/0x180 fs/file_table.c:187 path_openat+0xf5/0x2f80 fs/namei.c:3776 do_filp_open+0x1f1/0x430 fs/namei.c:3817 do_sys_openat2+0x15e/0x810 fs/open.c:1343 do_sys_open fs/open.c:1359 [inline] __do_sys_openat fs/open.c:1375 [inline] __se_sys_openat fs/open.c:1370 [inline] __x64_sys_openat+0x136/0x160 fs/open.c:1370 x64_sys_call+0x783/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:258 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 Freed by task 103: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x31/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:242 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:250 kasan_slab_free include/linux/kasan.h:178 [inline] slab_free_hook mm/slub.c:1750 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1776 slab_free mm/slub.c:3712 [inline] kmem_cache_free+0x12d/0x300 mm/slub.c:3737 security_file_free+0xd8/0xf0 security/security.c:1562 file_free fs/file_table.c:56 [inline] __fput+0x5f4/0x8f0 fs/file_table.c:333 ____fput+0x15/0x20 fs/file_table.c:348 task_work_run+0x1e1/0x250 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0x9b/0xb0 kernel/entry/common.c:177 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88811cb4e000 which belongs to the cache lsm_file_cache of size 16 The buggy address is located 0 bytes inside of 16-byte region [ffff88811cb4e000, ffff88811cb4e010) The buggy address belongs to the physical page: page:ffffea000472d380 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11cb4e flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 0000000000000000 dead000000000001 ffff8881001ea000 raw: 0000000000000000 0000000000800080 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 116, tgid 116 (udevd), ts 4866042723, free_ts 0 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2670 prep_new_page+0x1c/0x110 mm/page_alloc.c:2677 get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4583 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5924 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1967 [inline] new_slab+0x98/0x3d0 mm/slub.c:2020 ___slab_alloc+0x6bd/0xb20 mm/slub.c:3177 __slab_alloc+0x5e/0xa0 mm/slub.c:3263 slab_alloc_node mm/slub.c:3348 [inline] slab_alloc mm/slub.c:3392 [inline] __kmem_cache_alloc_lru mm/slub.c:3399 [inline] kmem_cache_alloc+0x1b0/0x330 mm/slub.c:3408 kmem_cache_zalloc include/linux/slab.h:689 [inline] lsm_file_alloc security/security.c:575 [inline] security_file_alloc+0x33/0x130 security/security.c:1543 __alloc_file+0xb5/0x2a0 fs/file_table.c:143 alloc_empty_file+0x97/0x180 fs/file_table.c:187 path_openat+0xf5/0x2f80 fs/namei.c:3776 do_filp_open+0x1f1/0x430 fs/namei.c:3817 do_sys_openat2+0x15e/0x810 fs/open.c:1343 do_sys_open fs/open.c:1359 [inline] __do_sys_openat fs/open.c:1375 [inline] __se_sys_openat fs/open.c:1370 [inline] __x64_sys_openat+0x136/0x160 fs/open.c:1370 page_owner free stack trace missing Memory state around the buggy address: ffff88811cb4df00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88811cb4df80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88811cb4e000: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc ^ ffff88811cb4e080: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc ffff88811cb4e100: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc ================================================================== EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem. EXT4-fs (loop0): unmounting filesystem.