================================================================== BUG: KASAN: slab-use-after-free in __ethtool_get_link_ksettings+0x190/0x1c0 net/ethtool/ioctl.c:443 Read of size 8 at addr ffff88802c6d42f0 by task kworker/0:7/28026 CPU: 0 UID: 0 PID: 28026 Comm: kworker/0:7 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events smc_ib_port_event_work Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x156/0x4c9 mm/kasan/report.c:482 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595 __ethtool_get_link_ksettings+0x190/0x1c0 net/ethtool/ioctl.c:443 __ethtool_get_link_ksettings+0x144/0x1c0 net/ethtool/ioctl.c:450 ib_get_eth_speed+0x13a/0xb40 drivers/infiniband/core/verbs.c:2054 rxe_query_port+0x12a/0x330 drivers/infiniband/sw/rxe/rxe_verbs.c:62 __ib_query_port drivers/infiniband/core/device.c:2120 [inline] ib_query_port drivers/infiniband/core/device.c:2152 [inline] ib_query_port+0x441/0x8a0 drivers/infiniband/core/device.c:2142 smc_ib_remember_port_attr net/smc/smc_ib.c:364 [inline] smc_ib_port_event_work+0x14c/0xbd0 net/smc/smc_ib.c:388 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 30725: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5219 [inline] __kvmalloc_node_noprof+0x360/0xa00 mm/slub.c:6711 alloc_netdev_mqs+0xd7/0x14f0 net/core/dev.c:12012 rtnl_create_link+0xc13/0xf80 net/core/rtnetlink.c:3648 rtnl_newlink_create net/core/rtnetlink.c:3830 [inline] __rtnl_newlink net/core/rtnetlink.c:3957 [inline] rtnl_newlink+0x13b8/0x2380 net/core/rtnetlink.c:4072 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6958 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] __sys_sendto+0x4aa/0x520 net/socket.c:2206 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 24017: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2687 [inline] slab_free mm/slub.c:6124 [inline] kfree+0x1f6/0x6b0 mm/slub.c:6442 device_release+0xa4/0x240 drivers/base/core.c:2565 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1f7/0x640 lib/kobject.c:737 netdev_run_todo+0x817/0x12c0 net/core/dev.c:11713 default_device_exit_batch+0x94b/0xc60 net/core/dev.c:13052 ops_exit_list net/core/net_namespace.c:205 [inline] ops_undo_list+0x363/0xab0 net/core/net_namespace.c:252 cleanup_net+0x499/0x920 net/core/net_namespace.c:704 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:467 ret_from_fork+0x754/0xd80 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 ffff88802c6d4000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 752 bytes inside of freed 4096-byte region [ffff88802c6d4000, ffff88802c6d5000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2c6d0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88802c6d1011 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88813fe56500 dead000000000122 0000000000000000 raw: 0000000000000000 0000200000040004 00000000f5000000 ffff88802c6d1011 head: 00fff00000000040 ffff88813fe56500 dead000000000122 0000000000000000 head: 0000000000000000 0000200000040004 00000000f5000000 ffff88802c6d1011 head: 00fff00000000003 ffffea0000b1b401 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 30725, tgid 30725 (syz-executor), ts 772572833775, free_ts 772484015980 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1888 prep_new_page mm/page_alloc.c:1896 [inline] get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3961 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5249 alloc_slab_page mm/slub.c:3255 [inline] allocate_slab mm/slub.c:3444 [inline] new_slab+0xa6/0x6d0 mm/slub.c:3502 refill_objects+0x26b/0x400 mm/slub.c:7134 refill_sheaf mm/slub.c:2804 [inline] alloc_full_sheaf mm/slub.c:2825 [inline] __pcs_replace_empty_main+0x19f/0x600 mm/slub.c:4588 alloc_from_pcs mm/slub.c:4681 [inline] slab_alloc_node mm/slub.c:4815 [inline] __do_kmalloc_node mm/slub.c:5218 [inline] __kmalloc_noprof+0x688/0x850 mm/slub.c:5231 kmalloc_noprof include/linux/slab.h:966 [inline] kzalloc_noprof include/linux/slab.h:1204 [inline] __register_sysctl_table+0xac/0x1650 fs/proc/proc_sysctl.c:1379 __addrconf_sysctl_register+0x1a2/0x360 net/ipv6/addrconf.c:7328 addrconf_sysctl_register net/ipv6/addrconf.c:7376 [inline] addrconf_sysctl_register+0x163/0x200 net/ipv6/addrconf.c:7365 ipv6_add_dev+0xaf2/0x1520 net/ipv6/addrconf.c:460 addrconf_notify+0x563/0x19c0 net/ipv6/addrconf.c:3655 notifier_call_chain+0x99/0x420 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x110 net/core/dev.c:2242 call_netdevice_notifiers_extack net/core/dev.c:2280 [inline] call_netdevice_notifiers net/core/dev.c:2294 [inline] register_netdevice+0x16e6/0x2210 net/core/dev.c:11444 virt_wifi_newlink+0x43e/0x8a0 drivers/net/wireless/virtual/virt_wifi.c:571 page last free pid 30725 tgid 30725 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1432 [inline] __free_frozen_pages+0x7ca/0x10a0 mm/page_alloc.c:2977 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4501 [inline] slab_alloc_node mm/slub.c:4830 [inline] __kmalloc_cache_noprof+0x243/0x6f0 mm/slub.c:5334 kmalloc_noprof include/linux/slab.h:962 [inline] __netdev_adjacent_dev_insert+0x22b/0xbf0 net/core/dev.c:8690 __netdev_adjacent_dev_link_lists net/core/dev.c:8782 [inline] __netdev_adjacent_dev_link_neighbour net/core/dev.c:8811 [inline] __netdev_upper_dev_link+0x3d8/0x7e0 net/core/dev.c:8871 netdev_master_upper_dev_link+0x9f/0xd0 net/core/dev.c:8946 hsr_portdev_setup net/hsr/hsr_slave.c:165 [inline] hsr_add_port+0x5d2/0xc00 net/hsr/hsr_slave.c:213 hsr_dev_finalize+0x7ef/0xd00 net/hsr/hsr_device.c:792 hsr_newlink+0x4ab/0xab0 net/hsr/hsr_netlink.c:128 rtnl_newlink_create net/core/rtnetlink.c:3840 [inline] __rtnl_newlink net/core/rtnetlink.c:3957 [inline] rtnl_newlink+0x1494/0x2380 net/core/rtnetlink.c:4072 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6958 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894 Memory state around the buggy address: ffff88802c6d4180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802c6d4200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802c6d4280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802c6d4300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802c6d4380: fb 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