================================================================== BUG: KASAN: slab-use-after-free in netdev_need_ops_lock include/net/netdev_lock.h:30 [inline] BUG: KASAN: slab-use-after-free in netdev_lock_ops include/net/netdev_lock.h:41 [inline] BUG: KASAN: slab-use-after-free in __ethtool_get_link_ksettings+0x230/0x250 net/ethtool/ioctl.c:463 Read of size 1 at addr ffff88805b401011 by task kworker/0:0/5672 CPU: 0 UID: 0 PID: 5672 Comm: kworker/0:0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Workqueue: events smc_ib_port_event_work 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 netdev_need_ops_lock include/net/netdev_lock.h:30 [inline] netdev_lock_ops include/net/netdev_lock.h:41 [inline] __ethtool_get_link_ksettings+0x230/0x250 net/ethtool/ioctl.c:463 __ethtool_get_link_ksettings+0x11f/0x250 net/ethtool/ioctl.c:464 ib_get_eth_speed+0x180/0x800 drivers/infiniband/core/verbs.c:2052 rxe_query_port+0x93/0x3e0 drivers/infiniband/sw/rxe/rxe_verbs.c:56 __ib_query_port drivers/infiniband/core/device.c:2129 [inline] ib_query_port+0x16e/0x840 drivers/infiniband/core/device.c:2161 smc_ib_remember_port_attr net/smc/smc_ib.c:364 [inline] smc_ib_port_event_work+0x15b/0x980 net/smc/smc_ib.c:388 process_one_work+0xaaf/0x1480 kernel/workqueue.c:3379 process_scheduled_works kernel/workqueue.c:3462 [inline] worker_thread+0xb05/0x10d0 kernel/workqueue.c:3543 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 5842: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5339 [inline] __kvmalloc_node_noprof+0x5ac/0x880 mm/slub.c:6916 alloc_netdev_mqs+0xa9/0x1300 net/core/dev.c:12078 rtnl_create_link+0x321/0xd70 net/core/rtnetlink.c:3757 rtnl_newlink_create+0x258/0x7b0 net/core/rtnetlink.c:3939 __rtnl_newlink net/core/rtnetlink.c:4078 [inline] rtnl_newlink+0x166d/0x1c30 net/core/rtnetlink.c:4195 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7112 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:810 __sock_sendmsg net/socket.c:825 [inline] __sys_sendto+0x41e/0x5d0 net/socket.c:2292 __do_sys_sendto net/socket.c:2299 [inline] __se_sys_sendto net/socket.c:2295 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2295 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x17b/0x530 arch/x86/entry/syscall_64.c:85 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 3178: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2706 [inline] slab_free mm/slub.c:6388 [inline] kfree+0x1c5/0x6c0 mm/slub.c:6703 device_release+0xc4/0x1f0 drivers/base/core.c:-1 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x222/0x550 lib/kobject.c:737 netdev_run_todo+0x1135/0x12b0 net/core/dev.c:11779 default_device_exit_batch+0x923/0x9a0 net/core/dev.c:13253 ops_exit_list net/core/net_namespace.c:206 [inline] ops_undo_list+0x4b4/0x8d0 net/core/net_namespace.c:253 cleanup_net+0x575/0x810 net/core/net_namespace.c:706 process_one_work+0xaaf/0x1480 kernel/workqueue.c:3379 process_scheduled_works kernel/workqueue.c:3462 [inline] worker_thread+0xb05/0x10d0 kernel/workqueue.c:3543 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 The buggy address belongs to the object at ffff88805b400000 which belongs to the cache kmalloc-cg-8k of size 8192 The buggy address is located 4113 bytes inside of freed 8192-byte region [ffff88805b400000, ffff88805b402000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5b400 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88805b402011 flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff88813fe54640 dead000000000122 0000000000000000 raw: 0000000000000000 0000400000020002 00000000f5000000 ffff88805b402011 head: 0080000000000040 ffff88813fe54640 dead000000000122 0000000000000000 head: 0000000000000000 0000400000020002 00000000f5000000 ffff88805b402011 head: 0080000000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd60c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5842, tgid 5842 (syz-executor), ts 442835395352 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871 prep_new_page mm/page_alloc.c:1879 [inline] get_page_from_freelist+0x264c/0x26c0 mm/page_alloc.c:3955 __alloc_frozen_pages_noprof+0x222/0x5b0 mm/page_alloc.c:5394 alloc_slab_page mm/slub.c:3295 [inline] allocate_slab+0x7c/0x5e0 mm/slub.c:3410 new_slab mm/slub.c:3456 [inline] refill_objects+0x2d8/0x350 mm/slub.c:7321 refill_sheaf mm/slub.c:2833 [inline] __pcs_replace_empty_main+0x330/0x690 mm/slub.c:4699 alloc_from_pcs mm/slub.c:4775 [inline] slab_alloc_node mm/slub.c:4909 [inline] __do_kmalloc_node mm/slub.c:5338 [inline] __kvmalloc_node_noprof+0x6ec/0x880 mm/slub.c:6916 alloc_netdev_mqs+0xa9/0x1300 net/core/dev.c:12078 rtnl_create_link+0x321/0xd70 net/core/rtnetlink.c:3757 veth_newlink+0x277/0xe00 drivers/net/veth.c:1851 rtnl_newlink_create+0x305/0x7b0 net/core/rtnetlink.c:3949 __rtnl_newlink net/core/rtnetlink.c:4078 [inline] rtnl_newlink+0x166d/0x1c30 net/core/rtnetlink.c:4195 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7112 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 page last free pid 5706 tgid 5706 ts 410209956653 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1418 [inline] free_pages_prepare+0x9c0/0xac0 mm/page_alloc.c:1463 __free_contig_range_common+0x174/0x340 mm/page_alloc.c:7019 __free_contig_range mm/page_alloc.c:7064 [inline] free_pages_bulk+0x48/0x120 mm/page_alloc.c:5280 vm_area_free_pages mm/vmalloc.c:3500 [inline] vfree+0x26f/0x510 mm/vmalloc.c:3549 kcov_put kernel/kcov.c:451 [inline] kcov_close+0x2e/0x60 kernel/kcov.c:556 __fput+0x42a/0xa80 fs/file_table.c:512 task_work_run+0x1d9/0x270 kernel/task_work.c:233 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x73a/0x2360 kernel/exit.c:1009 do_group_exit+0x22d/0x2f0 kernel/exit.c:1152 get_signal+0x121b/0x12c0 kernel/signal.c:3039 arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline] exit_to_user_mode_loop+0x104/0x730 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:339 [inline] do_syscall_64+0x33d/0x530 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88805b400f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805b400f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805b401000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805b401080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805b401100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================