================================================================== BUG: KASAN: use-after-free in ext4_xattr_delete_inode+0xc9a/0xca0 fs/ext4/xattr.c:2904 Read of size 4 at addr ffff888073fba000 by task syz-executor/4800 CPU: 0 PID: 4800 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 ext4_xattr_delete_inode+0xc9a/0xca0 fs/ext4/xattr.c:2904 ext4_evict_inode+0xc0c/0x1050 fs/ext4/inode.c:301 evict+0x4b6/0x8b0 fs/inode.c:647 d_delete_notify include/linux/fsnotify.h:267 [inline] vfs_rmdir+0x392/0x410 fs/namei.c:4170 do_rmdir+0x27f/0x710 fs/namei.c:4218 __do_sys_unlinkat fs/namei.c:4398 [inline] __se_sys_unlinkat fs/namei.c:4392 [inline] __x64_sys_unlinkat+0xc0/0xe0 fs/namei.c:4392 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: 0033:0x7f61263a4ef7 Code: 77 01 c3 48 c7 c2 d0 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 d0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc15e5c2d8 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f61263a4ef7 RDX: 0000000000000200 RSI: 00007ffc15e5d480 RDI: 00000000ffffff9c RBP: 00007f612640936c R08: 00000000000085d0 R09: 00000000ffffffff R10: 0000000000000100 R11: 0000000000000207 R12: 00007ffc15e5d480 R13: 00007f612640936c R14: 0000000000015305 R15: 0000000000000007 Allocated by task 4612: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x92/0xc0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x15d/0x280 mm/slub.c:3238 kmem_cache_zalloc include/linux/slab.h:728 [inline] __alloc_file+0x25/0x240 fs/file_table.c:132 alloc_empty_file+0x90/0x180 fs/file_table.c:181 alloc_file+0x5c/0x510 fs/file_table.c:223 alloc_file_pseudo+0x180/0x200 fs/file_table.c:263 __anon_inode_getfile fs/anon_inodes.c:109 [inline] anon_inode_getfile+0xc1/0x1a0 fs/anon_inodes.c:147 __pidfd_prepare+0x7e/0x140 kernel/fork.c:1939 copy_process+0x1f2f/0x3ec0 kernel/fork.c:2323 kernel_clone+0x23f/0x990 kernel/fork.c:2681 __do_sys_clone kernel/fork.c:2798 [inline] __se_sys_clone kernel/fork.c:2782 [inline] __x64_sys_clone+0x19a/0x210 kernel/fork.c:2782 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 0: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1710 [inline] slab_free_freelist_hook+0xec/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kmem_cache_free+0x8f/0x210 mm/slub.c:3520 rcu_do_batch kernel/rcu/tree.c:2523 [inline] rcu_core+0x96e/0x1650 kernel/rcu/tree.c:2763 handle_softirqs+0x336/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 Last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3011 [inline] call_rcu+0x189/0x900 kernel/rcu/tree.c:3091 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Second to last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 task_work_add+0x2f/0x1d0 kernel/task_work.c:38 fput_many+0xde/0x1a0 fs/file_table.c:367 filp_close+0x10e/0x150 fs/open.c:1371 do_close_on_exec+0x27b/0x360 fs/file.c:833 begin_new_exec+0x9c7/0x1180 fs/exec.c:1333 load_elf_binary+0x9af/0x2910 fs/binfmt_elf.c:1001 search_binary_handler fs/exec.c:1742 [inline] exec_binprm fs/exec.c:1783 [inline] bprm_execve+0xa8d/0x1740 fs/exec.c:1852 do_execveat_common+0x504/0x6b0 fs/exec.c:1957 do_execve fs/exec.c:2027 [inline] __do_sys_execve fs/exec.c:2103 [inline] __se_sys_execve fs/exec.c:2098 [inline] __x64_sys_execve+0x8e/0xa0 fs/exec.c:2098 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 ffff888073fba000 which belongs to the cache filp of size 464 The buggy address is located 0 bytes inside of 464-byte region [ffff888073fba000, ffff888073fba1d0) The buggy address belongs to the page: page:ffffea0001cfee80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x73fba head:ffffea0001cfee80 order:1 compound_mapcount:0 memcg:ffff888072549901 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff8881400068c0 raw: 0000000000000000 00000000000c000c 00000001ffffffff ffff888072549901 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4612, ts 75763068673, free_ts 57080123197 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x24f6/0x2670 mm/page_alloc.c:4192 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501 alloc_slab_page mm/slub.c:1780 [inline] allocate_slab mm/slub.c:1917 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1980 ___slab_alloc+0x807/0xdd0 mm/slub.c:3013 __slab_alloc mm/slub.c:3100 [inline] slab_alloc_node mm/slub.c:3191 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0xf0/0x280 mm/slub.c:3238 kmem_cache_zalloc include/linux/slab.h:728 [inline] __alloc_file+0x25/0x240 fs/file_table.c:132 alloc_empty_file+0x90/0x180 fs/file_table.c:181 alloc_file+0x5c/0x510 fs/file_table.c:223 alloc_file_pseudo+0x180/0x200 fs/file_table.c:263 __anon_inode_getfile fs/anon_inodes.c:109 [inline] anon_inode_getfile+0xc1/0x1a0 fs/anon_inodes.c:147 __pidfd_prepare+0x7e/0x140 kernel/fork.c:1939 copy_process+0x1f2f/0x3ec0 kernel/fork.c:2323 kernel_clone+0x23f/0x990 kernel/fork.c:2681 __do_sys_clone kernel/fork.c:2798 [inline] __se_sys_clone kernel/fork.c:2782 [inline] __x64_sys_clone+0x19a/0x210 kernel/fork.c:2782 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 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396 __vunmap+0x8e0/0xa80 mm/vmalloc.c:2628 kcov_put kernel/kcov.c:417 [inline] kcov_close+0x27/0x50 kernel/kcov.c:519 __fput+0x212/0x8c0 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x635/0x2110 kernel/exit.c:884 do_group_exit+0x12c/0x2f0 kernel/exit.c:998 get_signal+0x7eb/0x12e0 kernel/signal.c:2901 arch_do_signal_or_restart+0xe6/0x12a0 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Memory state around the buggy address: ffff888073fb9f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888073fb9f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888073fba000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888073fba080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888073fba100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================