================================================================== BUG: KASAN: use-after-free in ext4_xattr_delete_inode+0xba6/0xbb0 fs/ext4/xattr.c:2921 Read of size 4 at addr ffff88812bc87000 by task syz-executor/457 CPU: 1 PID: 457 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:88 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0xf1/0x140 mm/kasan/report.c:444 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308 ext4_xattr_delete_inode+0xba6/0xbb0 fs/ext4/xattr.c:2921 ext4_evict_inode+0xe44/0x1450 fs/ext4/inode.c:300 evict+0x485/0x870 fs/inode.c:650 iput_final fs/inode.c:1779 [inline] iput+0x635/0x7c0 fs/inode.c:1805 d_delete_notify include/linux/fsnotify.h:278 [inline] vfs_rmdir+0x33f/0x460 fs/namei.c:4170 do_rmdir+0x259/0x6a0 fs/namei.c:4218 __do_sys_unlinkat fs/namei.c:4398 [inline] __se_sys_unlinkat fs/namei.c:4392 [inline] __x64_sys_unlinkat+0xc7/0xf0 fs/namei.c:4392 x64_sys_call+0x4c0/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:264 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f13ba9edcf7 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 07 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:00007fff65fe0008 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f13ba9edcf7 RDX: 0000000000000200 RSI: 00007fff65fe11b0 RDI: 00000000ffffff9c RBP: 00007f13baa6123c R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000207 R12: 00007fff65fe11b0 R13: 00007f13baa6123c R14: 000000000000b219 R15: 00007fff65fe3360 Allocated by task 399: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:433 [inline] __kasan_slab_alloc+0xbd/0xf0 mm/kasan/common.c:466 kasan_slab_alloc include/linux/kasan.h:217 [inline] slab_post_alloc_hook+0x4f/0x2b0 mm/slab.h:550 slab_alloc_node mm/slub.c:3245 [inline] slab_alloc mm/slub.c:3255 [inline] kmem_cache_alloc+0xf7/0x260 mm/slub.c:3260 vm_area_dup+0x26/0x210 kernel/fork.c:368 __split_vma+0xac/0x3e0 mm/mmap.c:2753 __do_munmap+0x43b/0xfe0 mm/mmap.c:2891 __vm_munmap+0x15b/0x2a0 mm/mmap.c:2978 __do_sys_munmap mm/mmap.c:3004 [inline] __se_sys_munmap mm/mmap.c:3000 [inline] __x64_sys_munmap+0x6b/0x80 mm/mmap.c:3000 x64_sys_call+0xc9/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:12 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 365: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4a/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:365 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:373 kasan_slab_free include/linux/kasan.h:193 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1754 slab_free mm/slub.c:3526 [inline] kmem_cache_free+0x100/0x320 mm/slub.c:3544 __free_vm_area_struct+0x1c/0x20 kernel/fork.c:390 rcu_do_batch+0x51d/0xba0 kernel/rcu/tree.c:2523 rcu_core+0x5e4/0xf80 kernel/rcu/tree.c:2763 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2776 handle_softirqs+0x250/0x560 kernel/softirq.c:583 __do_softirq+0xb/0xd kernel/softirq.c:621 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 __call_rcu_common kernel/rcu/tree.c:3011 [inline] call_rcu+0x105/0xfe0 kernel/rcu/tree.c:3129 free_vm_area_struct kernel/fork.c:395 [inline] vm_area_free_no_check+0x10e/0x140 kernel/fork.c:409 vm_area_free+0x56/0x60 kernel/fork.c:419 remove_vma mm/mmap.c:191 [inline] remove_vma_list mm/mmap.c:2651 [inline] __do_munmap+0xc26/0xfe0 mm/mmap.c:2928 __vm_munmap+0x15b/0x2a0 mm/mmap.c:2978 __do_sys_munmap mm/mmap.c:3004 [inline] __se_sys_munmap mm/mmap.c:3000 [inline] __x64_sys_munmap+0x6b/0x80 mm/mmap.c:3000 x64_sys_call+0xc9/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:12 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88812bc87000 which belongs to the cache vm_area_struct of size 232 The buggy address is located 0 bytes inside of 232-byte region [ffff88812bc87000, ffff88812bc870e8) The buggy address belongs to the page: page:ffffea0004af21c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12bc87 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 0000000000000000 dead000000000122 ffff888100186180 raw: 0000000000000000 00000000000d000d 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 399, ts 45680896380, free_ts 45507235099 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605 prep_new_page+0x1c/0x110 mm/page_alloc.c:2611 get_page_from_freelist+0x2cc5/0x2d50 mm/page_alloc.c:4485 __alloc_pages+0x18f/0x440 mm/page_alloc.c:5808 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1937 [inline] new_slab+0xa1/0x4d0 mm/slub.c:2000 ___slab_alloc+0x381/0x810 mm/slub.c:3033 __slab_alloc+0x49/0x90 mm/slub.c:3120 slab_alloc_node mm/slub.c:3211 [inline] slab_alloc mm/slub.c:3255 [inline] kmem_cache_alloc+0x138/0x260 mm/slub.c:3260 vm_area_alloc+0x24/0x130 kernel/fork.c:360 __mmap_region mm/mmap.c:1794 [inline] mmap_region+0xa54/0x1800 mm/mmap.c:2959 do_mmap+0x812/0xf10 mm/mmap.c:1598 vm_mmap_pgoff+0x1ce/0x410 mm/util.c:555 ksys_mmap_pgoff+0xf6/0x1d0 mm/mmap.c:1647 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:93 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:86 [inline] __x64_sys_mmap+0xfa/0x110 arch/x86/kernel/sys_x86_64.c:86 x64_sys_call+0x83/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:10 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1472 [inline] free_pcp_prepare mm/page_alloc.c:1544 [inline] free_unref_page_prepare+0x542/0x550 mm/page_alloc.c:3534 free_unref_page_list+0x134/0x9d0 mm/page_alloc.c:3671 release_pages+0xfda/0x1030 mm/swap.c:1014 __pagevec_release+0x71/0xe0 mm/swap.c:1034 pagevec_release include/linux/pagevec.h:81 [inline] __invalidate_mapping_pages+0x45a/0x610 mm/truncate.c:517 invalidate_mapping_pages+0x27/0x30 mm/truncate.c:541 invalidate_bdev+0xa6/0x150 block/bdev.c:88 ext4_put_super+0x6cb/0xa70 fs/ext4/super.c:1247 generic_shutdown_super+0x151/0x330 fs/super.c:475 kill_block_super+0x7f/0xf0 fs/super.c:1427 deactivate_locked_super+0xa0/0x100 fs/super.c:335 deactivate_super+0xaf/0xe0 fs/super.c:366 cleanup_mnt+0x446/0x500 fs/namespace.c:1148 __cleanup_mnt+0x19/0x20 fs/namespace.c:1155 task_work_run+0x127/0x190 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181 Memory state around the buggy address: ffff88812bc86f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88812bc86f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88812bc87000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88812bc87080: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc ffff88812bc87100: fc fc fc fc fc fa fb 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