================================================================== BUG: KASAN: use-after-free in ext4_xattr_delete_inode+0xba6/0xbb0 fs/ext4/xattr.c:2921 Read of size 4 at addr ffff888120cc0000 by task syz-executor/453 CPU: 0 PID: 453 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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: 0033:0x7f9259153cf7 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:00007ffdbdf11a98 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f9259153cf7 RDX: 0000000000000200 RSI: 00007ffdbdf12c40 RDI: 00000000ffffff9c RBP: 00007f92591c71cc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000207 R12: 00007ffdbdf12c40 R13: 00007f92591c71cc R14: 000000000000b265 R15: 00007ffdbdf14df0 Allocated by task 409: 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 kmem_cache_zalloc include/linux/slab.h:740 [inline] __kernfs_new_node+0xdb/0x680 fs/kernfs/dir.c:593 kernfs_new_node+0x150/0x260 fs/kernfs/dir.c:669 kernfs_create_dir_ns+0x47/0x130 fs/kernfs/dir.c:1017 internal_create_group+0x20f/0xcf0 fs/sysfs/group.c:137 sysfs_create_group+0x1f/0x30 fs/sysfs/group.c:175 netdev_queue_add_kobject net/core/net-sysfs.c:1672 [inline] netdev_queue_update_kobjects+0x1b0/0x3e0 net/core/net-sysfs.c:1711 register_queue_kobjects net/core/net-sysfs.c:1772 [inline] netdev_register_kobject+0x26e/0x320 net/core/net-sysfs.c:2018 register_netdevice+0xdfa/0x13a0 net/core/dev.c:10405 veth_newlink+0x668/0xda0 drivers/net/veth.c:1683 __rtnl_newlink net/core/rtnetlink.c:3524 [inline] rtnl_newlink+0x112d/0x17b0 net/core/rtnetlink.c:3572 rtnetlink_rcv_msg+0x9e4/0xb90 net/core/rtnetlink.c:5650 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2511 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5668 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline] netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1348 netlink_sendmsg+0x86a/0xb70 net/netlink/af_netlink.c:1922 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x423/0x580 net/socket.c:2063 __do_sys_sendto net/socket.c:2075 [inline] __se_sys_sendto net/socket.c:2071 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2071 x64_sys_call+0x178/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:45 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 409: 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 kernfs_put+0x310/0x480 fs/kernfs/dir.c:547 sysfs_remove_group+0x286/0x2a0 fs/sysfs/group.c:293 netdev_queue_update_kobjects+0x373/0x3e0 net/core/net-sysfs.c:1724 netif_set_real_num_tx_queues+0x160/0x780 net/core/dev.c:2979 veth_init_queues+0x88/0x180 drivers/net/veth.c:1608 veth_newlink+0xab7/0xda0 drivers/net/veth.c:1732 __rtnl_newlink net/core/rtnetlink.c:3524 [inline] rtnl_newlink+0x112d/0x17b0 net/core/rtnetlink.c:3572 rtnetlink_rcv_msg+0x9e4/0xb90 net/core/rtnetlink.c:5650 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2511 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5668 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline] netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1348 netlink_sendmsg+0x86a/0xb70 net/netlink/af_netlink.c:1922 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x423/0x580 net/socket.c:2063 __do_sys_sendto net/socket.c:2075 [inline] __se_sys_sendto net/socket.c:2071 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2071 x64_sys_call+0x178/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:45 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 ffff888120cc0000 which belongs to the cache kernfs_node_cache of size 136 The buggy address is located 0 bytes inside of 136-byte region [ffff888120cc0000, ffff888120cc0088) The buggy address belongs to the page: page:ffffea0004833000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x120cc0 flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 0000000000000000 dead000000000122 ffff8881001c5c80 raw: 0000000000000000 0000000000140014 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 409, ts 44472453835, free_ts 36418659958 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 kmem_cache_zalloc include/linux/slab.h:740 [inline] __kernfs_new_node+0xdb/0x680 fs/kernfs/dir.c:593 kernfs_new_node+0x150/0x260 fs/kernfs/dir.c:669 __kernfs_create_file+0x4e/0x270 fs/kernfs/file.c:987 sysfs_add_file_mode_ns+0x29a/0x350 fs/sysfs/file.c:317 create_files fs/sysfs/group.c:64 [inline] internal_create_group+0x489/0xcf0 fs/sysfs/group.c:149 internal_create_groups fs/sysfs/group.c:189 [inline] sysfs_create_groups+0x58/0x120 fs/sysfs/group.c:215 create_dir lib/kobject.c:100 [inline] kobject_add_internal+0x8d4/0xda0 lib/kobject.c:263 kobject_add_varg lib/kobject.c:398 [inline] kobject_init_and_add+0x122/0x190 lib/kobject.c:481 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+0xa2/0x550 mm/page_alloc.c:3616 __put_single_page mm/swap.c:98 [inline] __put_page+0xad/0xe0 mm/swap.c:129 put_page include/linux/mm.h:1306 [inline] anon_pipe_buf_release+0x183/0x200 fs/pipe.c:137 pipe_buf_release include/linux/pipe_fs_i.h:219 [inline] pipe_read+0x53d/0xfe0 fs/pipe.c:323 call_read_iter include/linux/fs.h:2206 [inline] new_sync_read fs/read_write.c:404 [inline] vfs_read+0x68b/0xbe0 fs/read_write.c:485 ksys_read+0x140/0x240 fs/read_write.c:623 __do_sys_read fs/read_write.c:633 [inline] __se_sys_read fs/read_write.c:631 [inline] __x64_sys_read+0x7b/0x90 fs/read_write.c:631 x64_sys_call+0x96d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:1 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 Memory state around the buggy address: ffff888120cbff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888120cbff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888120cc0000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888120cc0080: fb fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb ffff888120cc0100: fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc ==================================================================