================================================================== BUG: KASAN: use-after-free in ext4_get_inode_usage+0x3a1/0x520 fs/ext4/xattr.c:817 Read of size 4 at addr ffff8881152fe070 by task syz.2.19/408 CPU: 1 PID: 408 Comm: syz.2.19 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:77 dump_stack_lvl+0x1a7/0x208 lib/dump_stack.c:118 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0xe2/0x130 mm/kasan/report.c:452 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308 ext4_get_inode_usage+0x3a1/0x520 fs/ext4/xattr.c:817 __dquot_transfer+0x192/0x20d0 fs/quota/dquot.c:2017 dquot_transfer+0x2f1/0x460 fs/quota/dquot.c:2169 ext4_setattr+0x715/0x1950 fs/ext4/inode.c:5577 notify_change+0xab3/0xe40 fs/attr.c:410 chown_common+0x335/0x500 fs/open.c:675 vfs_fchown fs/open.c:742 [inline] ksys_fchown+0xef/0x160 fs/open.c:753 __do_sys_fchown fs/open.c:761 [inline] __se_sys_fchown fs/open.c:759 [inline] __x64_sys_fchown+0x7a/0x90 fs/open.c:759 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f1240633e59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007fffc1cdb578 EFLAGS: 00000246 ORIG_RAX: 000000000000005d RAX: ffffffffffffffda RBX: 00007f12408acfa0 RCX: 00007f1240633e59 RDX: 000000000000ee01 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 00007f12406c9d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f12408acfac R14: 00007f12408acfa0 R15: 00007f12408acfa0 Allocated by task 108: 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:430 [inline] __kasan_slab_alloc+0xbd/0xf0 mm/kasan/common.c:463 kasan_slab_alloc include/linux/kasan.h:244 [inline] slab_post_alloc_hook+0x5d/0x2f0 mm/slab.h:580 slab_alloc_node mm/slub.c:2952 [inline] slab_alloc mm/slub.c:2960 [inline] kmem_cache_alloc+0x162/0x2d0 mm/slub.c:2965 kmem_cache_zalloc include/linux/slab.h:657 [inline] __alloc_file+0x28/0x320 fs/file_table.c:101 alloc_empty_file+0x97/0x180 fs/file_table.c:151 path_openat+0xf5/0x31c0 fs/namei.c:3503 do_filp_open+0x1e2/0x410 fs/namei.c:3544 do_sys_openat2+0x19f/0x750 fs/open.c:1219 do_sys_open fs/open.c:1235 [inline] __do_sys_openat fs/open.c:1251 [inline] __se_sys_openat fs/open.c:1246 [inline] __x64_sys_openat+0x136/0x160 fs/open.c:1246 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb 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 kernel/rcu/tree.c:2980 [inline] call_rcu+0x11a/0x10b0 kernel/rcu/tree.c:3054 file_free fs/file_table.c:58 [inline] __fput+0x5ad/0x770 fs/file_table.c:299 ____fput+0x15/0x20 fs/file_table.c:314 task_work_run+0x127/0x190 kernel/task_work.c:189 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop+0xcb/0xe0 kernel/entry/common.c:172 exit_to_user_mode_prepare+0x76/0xa0 kernel/entry/common.c:199 syscall_exit_to_user_mode+0x1d/0x40 kernel/entry/common.c:274 do_syscall_64+0x3d/0x40 arch/x86/entry/common.c:56 entry_SYSCALL_64_after_hwframe+0x61/0xcb Second to 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+0xe/0x10 mm/kasan/generic.c:353 task_work_add+0x27/0x1e0 kernel/task_work.c:38 fput_many+0xe7/0x1a0 fs/file_table.c:342 fput+0x1a/0x20 fs/file_table.c:358 filp_close+0x105/0x150 fs/open.c:1335 __close_fd+0x44/0x50 fs/file.c:716 __do_sys_close fs/open.c:1348 [inline] __se_sys_close fs/open.c:1346 [inline] __x64_sys_close+0x66/0xb0 fs/open.c:1346 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb The buggy address belongs to the object at ffff8881152fe000 which belongs to the cache filp of size 296 The buggy address is located 112 bytes inside of 296-byte region [ffff8881152fe000, ffff8881152fe128) The buggy address belongs to the page: page:ffffea000454bf80 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8881152ff380 pfn:0x1152fe head:ffffea000454bf80 order:1 compound_mapcount:0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 ffffea000454be80 0000000300000003 ffff88810018aa80 raw: ffff8881152ff380 0000000080150000 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 97, ts 4097082040, free_ts 0 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x179/0x180 mm/page_alloc.c:2462 get_page_from_freelist+0x223b/0x23d0 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x290/0x620 mm/page_alloc.c:5384 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1813 [inline] new_slab+0x84/0x3f0 mm/slub.c:1874 new_slab_objects mm/slub.c:2632 [inline] ___slab_alloc+0x2a6/0x450 mm/slub.c:2796 __slab_alloc+0x63/0xa0 mm/slub.c:2836 slab_alloc_node mm/slub.c:2918 [inline] slab_alloc mm/slub.c:2960 [inline] kmem_cache_alloc+0x1ac/0x2d0 mm/slub.c:2965 kmem_cache_zalloc include/linux/slab.h:657 [inline] __alloc_file+0x28/0x320 fs/file_table.c:101 alloc_empty_file+0x97/0x180 fs/file_table.c:151 path_openat+0xf5/0x31c0 fs/namei.c:3503 do_filp_open+0x1e2/0x410 fs/namei.c:3544 do_sys_openat2+0x19f/0x750 fs/open.c:1219 do_sys_open fs/open.c:1235 [inline] __do_sys_openat fs/open.c:1251 [inline] __se_sys_openat fs/open.c:1246 [inline] __x64_sys_openat+0x136/0x160 fs/open.c:1246 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb page_owner free stack trace missing Memory state around the buggy address: ffff8881152fdf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881152fdf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881152fe000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881152fe080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881152fe100: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc ==================================================================