================================================================== 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 ffff8880331d0e09 by task kworker/0:3/5614 CPU: 0 UID: 0 PID: 5614 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT(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+0x180/0x7f0 drivers/infiniband/core/verbs.c:2052 rxe_query_port+0x93/0x3d0 drivers/infiniband/sw/rxe/rxe_verbs.c:56 __ib_query_port drivers/infiniband/core/device.c:2129 [inline] ib_query_port+0x16e/0x830 drivers/infiniband/core/device.c:2161 smc_ib_remember_port_attr net/smc/smc_ib.c:364 [inline] smc_ib_port_event_work+0x147/0x920 net/smc/smc_ib.c:388 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa88/0x14c0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x38b/0x480 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 5627: 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:5334 [inline] __kvmalloc_node_noprof+0x543/0x870 mm/slub.c:6905 alloc_netdev_mqs+0xa9/0x12a0 net/core/dev.c:12117 rtnl_create_link+0x321/0xd70 net/core/rtnetlink.c:3777 rtnl_newlink_create+0x258/0x7b0 net/core/rtnetlink.c:3959 __rtnl_newlink net/core/rtnetlink.c:4098 [inline] rtnl_newlink+0x166d/0x1c30 net/core/rtnetlink.c:4215 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7132 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x7bd/0x940 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec+0x13a/0x180 net/socket.c:800 __sock_sendmsg net/socket.c:815 [inline] __sys_sendto+0x408/0x5a0 net/socket.c:2281 __do_sys_sendto net/socket.c:2288 [inline] __se_sys_sendto net/socket.c:2284 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2284 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5919: 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:2677 [inline] slab_free mm/slub.c:6377 [inline] kfree+0x1c5/0x640 mm/slub.c:6692 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+0xeee/0x1060 net/core/dev.c:11818 default_device_exit_batch+0x923/0x9a0 net/core/dev.c:13289 ops_exit_list net/core/net_namespace.c:206 [inline] ops_undo_list+0x4b4/0x8d0 net/core/net_namespace.c:253 cleanup_net+0x572/0x810 net/core/net_namespace.c:706 process_one_work kernel/workqueue.c:3322 [inline] process_scheduled_works+0xa88/0x14c0 kernel/workqueue.c:3405 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486 kthread+0x38b/0x480 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 ffff8880331d0000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 3593 bytes inside of freed 4096-byte region [ffff8880331d0000, ffff8880331d1000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880331d2000 pfn:0x331d0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888042412901 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88801b00b500 ffffea0001a55a10 ffffea00009c9610 raw: ffff8880331d2000 0000000800040003 00000000f5000000 ffff888042412901 head: 00fff00000000240 ffff88801b00b500 ffffea0001a55a10 ffffea00009c9610 head: ffff8880331d2000 0000000800040003 00000000f5000000 ffff888042412901 head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5626, tgid 5626 (syz-executor), ts 86617403497, free_ts 65609005278 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+0x21fe/0x2270 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+0x2d5/0x350 mm/slub.c:7310 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x2c3/0x6b0 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] __do_kmalloc_node mm/slub.c:5333 [inline] __kmalloc_node_track_caller_noprof+0x55b/0x740 mm/slub.c:5471 kmemdup_noprof+0x2b/0x70 mm/util.c:138 kmemdup_noprof include/linux/fortify-string.h:715 [inline] __addrconf_sysctl_register+0xa7/0x4b0 net/ipv6/addrconf.c:7334 addrconf_sysctl_register+0x168/0x1c0 net/ipv6/addrconf.c:7400 ipv6_add_dev+0xd26/0x13a0 net/ipv6/addrconf.c:460 addrconf_notify+0x771/0x1050 net/ipv6/addrconf.c:3686 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2313 [inline] call_netdevice_notifiers net/core/dev.c:2327 [inline] register_netdevice+0x18a4/0x1eb0 net/core/dev.c:11541 ipvlan_link_new+0x3e6/0xa10 drivers/net/ipvlan/ipvlan_main.c:647 rtnl_newlink_create+0x305/0x7b0 net/core/rtnetlink.c:3969 page last free pid 5455 tgid 5455 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1406 [inline] __free_frozen_pages+0xc22/0xd20 mm/page_alloc.c:2950 __slab_free+0x274/0x2c0 mm/slub.c:5741 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 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_node_noprof+0x359/0x620 mm/slub.c:4989 __alloc_skb+0x1db/0x7a0 net/core/skbuff.c:704 alloc_skb_fclone include/linux/skbuff.h:1434 [inline] tcp_stream_alloc_skb+0x3f/0x580 net/ipv4/tcp.c:931 tcp_sendmsg_locked+0x1437/0x55c0 net/ipv4/tcp.c:1256 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1451 sock_sendmsg_nosec+0x10e/0x180 net/socket.c:801 __sock_sendmsg net/socket.c:815 [inline] sock_write_iter+0x2de/0x3e0 net/socket.c:1266 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x612/0xba0 fs/read_write.c:687 ksys_write+0x150/0x270 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff8880331d0d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880331d0d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880331d0e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880331d0e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880331d0f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================