================================================================== BUG: KASAN: use-after-free in ext4_xattr_delete_inode+0xba6/0xbb0 fs/ext4/xattr.c:2920 Read of size 4 at addr ffff888117985000 by task syz-executor/456 CPU: 1 PID: 456 Comm: syz-executor Not tainted 5.15.185-syzkaller-1080790-g32c443bd6d40 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:2920 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:4162 do_rmdir+0x259/0x6a0 fs/namei.c:4210 __do_sys_unlinkat fs/namei.c:4390 [inline] __se_sys_unlinkat fs/namei.c:4384 [inline] __x64_sys_unlinkat+0xc7/0xf0 fs/namei.c:4384 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: 0033:0x7f0b3c3b3cf7 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:00007ffece6d8848 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f0b3c3b3cf7 RDX: 0000000000000200 RSI: 00007ffece6d99f0 RDI: 00000000ffffff9c RBP: 00007f0b3c4271cc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000207 R12: 00007ffece6d99f0 R13: 00007f0b3c4271cc R14: 000000000000c945 R15: 00007ffece6dbba0 Allocated by task 402: 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_kmalloc mm/kasan/common.c:512 [inline] __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:521 kasan_kmalloc include/linux/kasan.h:227 [inline] kmem_cache_alloc_trace+0x119/0x270 mm/slub.c:3269 kmalloc include/linux/slab.h:616 [inline] kernfs_get_open_node fs/kernfs/file.c:552 [inline] kernfs_fop_open+0x86b/0xb30 fs/kernfs/file.c:698 do_dentry_open+0x834/0x1010 fs/open.c:828 vfs_open+0x73/0x80 fs/open.c:958 do_open fs/namei.c:3608 [inline] path_openat+0x2646/0x2f10 fs/namei.c:3742 do_filp_open+0x1b3/0x3e0 fs/namei.c:3769 do_sys_openat2+0x14c/0x7b0 fs/open.c:1234 do_sys_open fs/open.c:1250 [inline] __do_sys_openat fs/open.c:1266 [inline] __se_sys_openat fs/open.c:1261 [inline] __x64_sys_openat+0x136/0x160 fs/open.c:1261 x64_sys_call+0x219/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:258 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 402: 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:1723 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1749 slab_free mm/slub.c:3521 [inline] kfree+0xc4/0x270 mm/slub.c:4583 kernfs_put_open_node+0x21e/0x230 fs/kernfs/file.c:594 kernfs_fop_release+0x1a2/0x250 fs/kernfs/file.c:760 __fput+0x20b/0x8b0 fs/file_table.c:311 ____fput+0x15/0x20 fs/file_table.c:339 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 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff888117985000 which belongs to the cache kmalloc-64 of size 64 The buggy address is located 0 bytes inside of 64-byte region [ffff888117985000, ffff888117985040) The buggy address belongs to the page: page:ffffea00045e6140 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x117985 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 0000000000000000 0000000100000001 ffff888100042780 raw: 0000000000000000 0000000000200020 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 109, ts 4835560344, free_ts 0 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:5795 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1932 [inline] new_slab+0xa1/0x4d0 mm/slub.c:1995 ___slab_alloc+0x381/0x810 mm/slub.c:3028 __slab_alloc+0x49/0x90 mm/slub.c:3115 slab_alloc_node mm/slub.c:3206 [inline] slab_alloc mm/slub.c:3250 [inline] __kmalloc+0x16a/0x2c0 mm/slub.c:4427 __kmalloc_node include/linux/slab.h:484 [inline] kmalloc_node include/linux/slab.h:639 [inline] kvmalloc_node+0x242/0x330 mm/util.c:628 kvmalloc include/linux/mm.h:851 [inline] vmemdup_user+0x26/0xe0 mm/util.c:203 setxattr_copy fs/xattr.c:564 [inline] setxattr+0x1e6/0x300 fs/xattr.c:607 path_setxattr+0x142/0x280 fs/xattr.c:630 __do_sys_lsetxattr fs/xattr.c:653 [inline] __se_sys_lsetxattr fs/xattr.c:649 [inline] __x64_sys_lsetxattr+0xc2/0xe0 fs/xattr.c:649 x64_sys_call+0x8cc/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:190 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_owner free stack trace missing Memory state around the buggy address: ffff888117984f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888117984f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888117985000: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ^ ffff888117985080: 00 00 00 00 00 00 00 02 fc fc fc fc fc fc fc fc ffff888117985100: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================