================================================================== 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 ffff888067d84e09 by task kworker/0:2/187 CPU: 0 UID: 0 PID: 187 Comm: kworker/0:2 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 8821: 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 7748: 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 ffff888067d84000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 3593 bytes inside of freed 4096-byte region [ffff888067d84000, ffff888067d85000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x67d80 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888067d81011 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b00b500 dead000000000122 0000000000000000 raw: 0000000000000000 0000200000040004 00000000f5000000 ffff888067d81011 head: 00fff00000000040 ffff88801b00b500 dead000000000122 0000000000000000 head: 0000000000000000 0000200000040004 00000000f5000000 ffff888067d81011 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 8821, tgid 8821 (syz-executor), ts 262753587848, free_ts 262472245390 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_noprof+0x489/0x720 mm/slub.c:5359 _kmalloc_noprof include/linux/slab.h:992 [inline] _kzalloc_noprof include/linux/slab.h:1309 [inline] __register_sysctl_table+0x6f/0x1370 fs/proc/proc_sysctl.c:1378 __addrconf_sysctl_register+0x31c/0x4b0 net/ipv6/addrconf.c:7352 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 virt_wifi_newlink+0x3be/0x7c0 drivers/net/wireless/virtual/virt_wifi.c:572 rtnl_newlink_create+0x305/0x7b0 net/core/rtnetlink.c:3969 page last free pid 5810 tgid 5810 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_noprof+0x2a4/0x5f0 mm/slub.c:4931 alloc_filename fs/namei.c:147 [inline] do_getname+0x2e/0x250 fs/namei.c:187 getname include/linux/fs.h:2543 [inline] getname_maybe_null include/linux/fs.h:2550 [inline] class_filename_maybe_null_constructor include/linux/fs.h:2574 [inline] vfs_fstatat+0x45/0x170 fs/stat.c:368 __do_sys_newfstatat fs/stat.c:538 [inline] __se_sys_newfstatat fs/stat.c:532 [inline] __x64_sys_newfstatat+0x151/0x200 fs/stat.c:532 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: ffff888067d84d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888067d84d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888067d84e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888067d84e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888067d84f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================