================================================================== BUG: KASAN: slab-out-of-bounds in memcpy_from_iter lib/iov_iter.c:85 [inline] BUG: KASAN: slab-out-of-bounds in iterate_bvec include/linux/iov_iter.h:123 [inline] BUG: KASAN: slab-out-of-bounds in iterate_and_advance2 include/linux/iov_iter.h:306 [inline] BUG: KASAN: slab-out-of-bounds in iterate_and_advance include/linux/iov_iter.h:330 [inline] BUG: KASAN: slab-out-of-bounds in __copy_from_iter lib/iov_iter.c:261 [inline] BUG: KASAN: slab-out-of-bounds in copy_folio_from_iter_atomic+0xbbf/0x1a30 lib/iov_iter.c:491 Read of size 4096 at addr ffff88805e700000 by task kworker/u8:14/3589 CPU: 0 UID: 0 PID: 3589 Comm: kworker/u8:14 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: loop0 loop_workfn Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x264/0x2c0 mm/kasan/generic.c:200 __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105 memcpy_from_iter lib/iov_iter.c:85 [inline] iterate_bvec include/linux/iov_iter.h:123 [inline] iterate_and_advance2 include/linux/iov_iter.h:306 [inline] iterate_and_advance include/linux/iov_iter.h:330 [inline] __copy_from_iter lib/iov_iter.c:261 [inline] copy_folio_from_iter_atomic+0xbbf/0x1a30 lib/iov_iter.c:491 generic_perform_write+0x5a8/0x8b0 mm/filemap.c:4376 shmem_file_write_iter+0xfb/0x120 mm/shmem.c:3424 lo_rw_aio+0xc78/0xf30 include/linux/percpu-rwsem.h:-1 do_req_filebacked drivers/block/loop.c:429 [inline] loop_handle_cmd drivers/block/loop.c:1917 [inline] loop_process_work+0x638/0x11d0 drivers/block/loop.c:1952 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 5878: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4584 [inline] slab_alloc_node mm/slub.c:4917 [inline] kmem_cache_alloc_noprof+0x355/0x650 mm/slub.c:4931 __kernfs_new_node+0xe7/0xa70 fs/kernfs/dir.c:665 kernfs_new_node+0xea/0x140 fs/kernfs/dir.c:751 __kernfs_create_file+0x4b/0x2e0 fs/kernfs/file.c:1050 sysfs_add_file_mode_ns+0x237/0x300 fs/sysfs/file.c:316 create_files fs/sysfs/group.c:82 [inline] internal_create_group+0x679/0x1180 fs/sysfs/group.c:189 internal_create_groups fs/sysfs/group.c:229 [inline] sysfs_create_groups+0x59/0x120 fs/sysfs/group.c:255 netdev_queue_add_kobject net/core/net-sysfs.c:1982 [inline] netdev_queue_update_kobjects+0x297/0x6a0 net/core/net-sysfs.c:2035 register_queue_kobjects net/core/net-sysfs.c:2098 [inline] netdev_register_kobject+0x258/0x310 net/core/net-sysfs.c:2341 register_netdevice+0x1455/0x1ed0 net/core/dev.c:11446 rtnl_newlink_create+0x31f/0xb00 net/core/rtnetlink.c:3915 __rtnl_newlink net/core/rtnetlink.c:4044 [inline] rtnl_newlink+0x167f/0x1bd0 net/core/rtnetlink.c:4159 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7076 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7f5/0x990 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:775 __sock_sendmsg net/socket.c:790 [inline] __sys_sendto+0x41e/0x5d0 net/socket.c:2252 __do_sys_sendto net/socket.c:2259 [inline] __se_sys_sendto net/socket.c:2255 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2255 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88805e700000 which belongs to the cache kernfs_node_cache of size 176 The buggy address is located 0 bytes inside of allocated 176-byte region [ffff88805e700000, ffff88805e7000b0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88805e700780 pfn:0x5e700 flags: 0x80000000000200(workingset|node=0|zone=1) page_type: f5(slab) raw: 0080000000000200 ffff888140411000 ffff88801bafe188 ffff88801bafe188 raw: ffff88805e700780 0000000800110008 00000000f5000000 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 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5878, tgid 5878 (syz-executor), ts 117430994704, free_ts 117396899984 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859 prep_new_page mm/page_alloc.c:1867 [inline] get_page_from_freelist+0x262a/0x26a0 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304 alloc_slab_page mm/slub.c:3266 [inline] allocate_slab+0x79/0x5e0 mm/slub.c:3380 new_slab mm/slub.c:3426 [inline] refill_objects+0x2d8/0x350 mm/slub.c:7310 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x330/0x690 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] kmem_cache_alloc_noprof+0x452/0x650 mm/slub.c:4931 __kernfs_new_node+0xe7/0xa70 fs/kernfs/dir.c:665 kernfs_new_node fs/kernfs/dir.c:751 [inline] kernfs_create_dir_ns+0xfe/0x230 fs/kernfs/dir.c:1120 sysfs_create_dir_ns+0x12f/0x2a0 fs/sysfs/dir.c:59 create_dir lib/kobject.c:73 [inline] kobject_add_internal+0x62c/0xce0 lib/kobject.c:240 kobject_add_varg lib/kobject.c:374 [inline] kobject_init_and_add+0x12b/0x1a0 lib/kobject.c:457 netdev_queue_add_kobject net/core/net-sysfs.c:1976 [inline] netdev_queue_update_kobjects+0x246/0x6a0 net/core/net-sysfs.c:2035 register_queue_kobjects net/core/net-sysfs.c:2098 [inline] netdev_register_kobject+0x258/0x310 net/core/net-sysfs.c:2341 register_netdevice+0x1455/0x1ed0 net/core/dev.c:11446 rtnl_newlink_create+0x31f/0xb00 net/core/rtnetlink.c:3915 page last free pid 5611 tgid 5611 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0x10e7/0x11c0 mm/page_alloc.c:2950 lbmLogShutdown fs/jfs/jfs_logmgr.c:1861 [inline] lmLogShutdown+0x44e/0x850 fs/jfs/jfs_logmgr.c:1681 lmLogClose+0x28c/0x530 fs/jfs/jfs_logmgr.c:1457 jfs_umount+0x2da/0x3b0 fs/jfs/jfs_umount.c:124 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x13d/0x2d0 fs/super.c:647 kill_block_super+0x44/0x90 fs/super.c:1671 deactivate_locked_super+0xbc/0x130 fs/super.c:477 cleanup_mnt+0x3d3/0x460 fs/namespace.c:1317 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:70 [inline] exit_to_user_mode_loop+0x1fa/0x730 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88805e6fff80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff88805e700000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88805e700080: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc 00 00 ^ ffff88805e700100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88805e700180: 00 00 00 00 fc fc fc fc fc fc fc fc 00 00 00 00 ==================================================================