================================================================== BUG: KASAN: slab-use-after-free in __ethtool_get_link_ksettings+0x6e/0x190 net/ethtool/ioctl.c:443 Read of size 8 at addr ffff8880298542e8 by task kworker/1:1/43 CPU: 1 UID: 0 PID: 43 Comm: kworker/1:1 Not tainted 6.16.0-rc4-syzkaller-00109-gb9fd9888a565 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events smc_ib_port_event_work Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xd2/0x2b0 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 __ethtool_get_link_ksettings+0x6e/0x190 net/ethtool/ioctl.c:443 ib_get_eth_speed+0x15e/0x7b0 drivers/infiniband/core/verbs.c:1996 rxe_query_port+0x93/0x3b0 drivers/infiniband/sw/rxe/rxe_verbs.c:62 __ib_query_port drivers/infiniband/core/device.c:2111 [inline] ib_query_port+0x16d/0x830 drivers/infiniband/core/device.c:2143 smc_ib_remember_port_attr net/smc/smc_ib.c:364 [inline] smc_ib_port_event_work+0x15a/0x940 net/smc/smc_ib.c:388 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 5971: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4328 [inline] __kvmalloc_node_noprof+0x30d/0x5f0 mm/slub.c:5015 alloc_netdev_mqs+0xa6/0x11e0 net/core/dev.c:11711 rtnl_create_link+0x31f/0xd10 net/core/rtnetlink.c:3631 rtnl_newlink_create+0x25c/0xb00 net/core/rtnetlink.c:3813 __rtnl_newlink net/core/rtnetlink.c:3940 [inline] rtnl_newlink+0x16d6/0x1c70 net/core/rtnetlink.c:4055 rtnetlink_rcv_msg+0x7cc/0xb70 net/core/rtnetlink.c:6944 netlink_rcv_skb+0x205/0x470 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 __sys_sendto+0x3bd/0x520 net/socket.c:2180 __do_sys_sendto net/socket.c:2187 [inline] __se_sys_sendto net/socket.c:2183 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2183 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888029854000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 744 bytes inside of freed 4096-byte region [ffff888029854000, ffff888029855000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x29850 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff8880243167c1 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801a44b500 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000040004 00000000f5000000 ffff8880243167c1 head: 00fff00000000040 ffff88801a44b500 dead000000000122 0000000000000000 head: 0000000000000000 0000000000040004 00000000f5000000 ffff8880243167c1 head: 00fff00000000003 ffffea0000a61401 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 5971, tgid 5971 (syz-executor), ts 184422095396, free_ts 184391141883 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419 alloc_slab_page mm/slub.c:2451 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2619 new_slab mm/slub.c:2673 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3859 __slab_alloc mm/slub.c:3949 [inline] __slab_alloc_node mm/slub.c:4024 [inline] slab_alloc_node mm/slub.c:4185 [inline] __do_kmalloc_node mm/slub.c:4327 [inline] __kmalloc_node_track_caller_noprof+0x2f8/0x4e0 mm/slub.c:4347 kmemdup_noprof+0x2b/0x70 mm/util.c:137 kmemdup_noprof include/linux/fortify-string.h:765 [inline] __addrconf_sysctl_register+0x9c/0x530 net/ipv6/addrconf.c:7230 addrconf_sysctl_register+0x168/0x1c0 net/ipv6/addrconf.c:7296 ipv6_add_dev+0xd46/0x1370 net/ipv6/addrconf.c:458 addrconf_notify+0x794/0x1010 net/ipv6/addrconf.c:3654 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2268 [inline] call_netdevice_notifiers net/core/dev.c:2282 [inline] register_netdevice+0x1608/0x1ae0 net/core/dev.c:11143 virt_wifi_newlink+0x428/0x860 drivers/net/wireless/virtual/virt_wifi.c:569 rtnl_newlink_create+0x30d/0xb00 net/core/rtnetlink.c:3823 page last free pid 5205 tgid 5205 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706 discard_slab mm/slub.c:2717 [inline] __put_partials+0x161/0x1c0 mm/slub.c:3186 put_cpu_partial+0x17c/0x250 mm/slub.c:3261 __slab_free+0x2f7/0x400 mm/slub.c:4513 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4249 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:660 alloc_skb include/linux/skbuff.h:1336 [inline] alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6665 sock_alloc_send_pskb+0x857/0x990 net/core/sock.c:2999 unix_dgram_sendmsg+0x4f6/0x1870 net/unix/af_unix.c:2083 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 __sys_sendto+0x3bd/0x520 net/socket.c:2180 __do_sys_sendto net/socket.c:2187 [inline] __se_sys_sendto net/socket.c:2183 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2183 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 Memory state around the buggy address: ffff888029854180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888029854200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888029854280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888029854300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888029854380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================