syzbot

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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+0x25a/0x2a0 net/ethtool/ioctl.c:463
Read of size 1 at addr ffff8880555fce09 by task kworker/0:3/5731

CPU: 0 UID: 0 PID: 5731 Comm: kworker/0:3 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
Workqueue: events smc_ib_port_event_work
Call Trace:
 <TASK>
 __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+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report+0xdf/0x1c0 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+0x25a/0x2a0 net/ethtool/ioctl.c:463
 netif_get_link_ksettings+0x1f2/0x360 net/ethtool/ioctl.c:451
 __ethtool_get_link_ksettings+0xcf/0x2a0 net/ethtool/ioctl.c:464
 ib_get_eth_speed+0x13a/0xb40 drivers/infiniband/core/verbs.c:2052
 rxe_query_port+0x12a/0x330 drivers/infiniband/sw/rxe/rxe_verbs.c:56
 __ib_query_port drivers/infiniband/core/device.c:2129 [inline]
 ib_query_port drivers/infiniband/core/device.c:2161 [inline]
 ib_query_port+0x445/0x8b0 drivers/infiniband/core/device.c:2151
 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+0xa23/0x1940 kernel/workqueue.c:3322
 process_scheduled_works kernel/workqueue.c:3405 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 5763:
 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:5362 [inline]
 __kvmalloc_node_noprof+0x34f/0x970 mm/slub.c:6933
 alloc_netdev_mqs+0xd7/0x15c0 net/core/dev.c:12048
 rtnl_create_link+0xc13/0xf80 net/core/rtnetlink.c:3721
 rtnl_newlink_create net/core/rtnetlink.c:3903 [inline]
 __rtnl_newlink net/core/rtnetlink.c:4044 [inline]
 rtnl_newlink+0x13bd/0x2380 net/core/rtnetlink.c:4159
 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:7076
 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2556
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:775 [inline]
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x48b/0x4e0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2255
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 3012:
 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:2705 [inline]
 slab_free mm/slub.c:6405 [inline]
 kfree+0x22b/0x6c0 mm/slub.c:6720
 device_release+0xd2/0x270 drivers/base/core.c:2636
 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+0xa10/0x1600 net/core/dev.c:11749
 default_device_exit_batch+0x92b/0xc10 net/core/dev.c:13094
 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:702
 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
 process_scheduled_works kernel/workqueue.c:3405 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 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 ffff8880555fc000
 which belongs to the cache kmalloc-cg-4k of size 4096
The buggy address is located 3593 bytes inside of
 freed 4096-byte region [ffff8880555fc000, ffff8880555fd000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x555f8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff8880555f9011
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88813fe3d500 dead000000000122 0000000000000000
raw: 0000000000000000 0000200000040004 00000000f5000000 ffff8880555f9011
head: 00fff00000000040 ffff88813fe3d500 dead000000000122 0000000000000000
head: 0000000000000000 0000200000040004 00000000f5000000 ffff8880555f9011
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 5763, tgid 5763 (syz-executor), ts 80204783457, free_ts 77694008209
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304
 alloc_slab_page mm/slub.c:3294 [inline]
 allocate_slab mm/slub.c:3408 [inline]
 new_slab+0xa2/0x650 mm/slub.c:3454
 refill_objects+0xe3/0x410 mm/slub.c:7338
 refill_sheaf mm/slub.c:2832 [inline]
 __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4703
 alloc_from_pcs mm/slub.c:4801 [inline]
 slab_alloc_node mm/slub.c:4933 [inline]
 __do_kmalloc_node mm/slub.c:5361 [inline]
 __kmalloc_noprof+0x66d/0x820 mm/slub.c:5387
 _kmalloc_noprof include/linux/slab.h:973 [inline]
 _kzalloc_noprof include/linux/slab.h:1290 [inline]
 __register_sysctl_table+0xac/0x1650 fs/proc/proc_sysctl.c:1378
 __addrconf_sysctl_register+0x1a2/0x360 net/ipv6/addrconf.c:7366
 addrconf_sysctl_register net/ipv6/addrconf.c:7414 [inline]
 addrconf_sysctl_register+0x163/0x200 net/ipv6/addrconf.c:7403
 ipv6_add_dev+0xaf2/0x1520 net/ipv6/addrconf.c:460
 addrconf_notify+0x5db/0x1ba0 net/ipv6/addrconf.c:3685
 notifier_call_chain+0x99/0x3f0 kernel/notifier.c:85
 call_netdevice_notifiers_info+0xbe/0x110 net/core/dev.c:2250
 call_netdevice_notifiers_extack net/core/dev.c:2288 [inline]
 call_netdevice_notifiers net/core/dev.c:2302 [inline]
 register_netdevice+0x1998/0x25a0 net/core/dev.c:11478
 virt_wifi_newlink+0x3ec/0x840 drivers/net/wireless/virtual/virt_wifi.c:572
page last free pid 5708 tgid 5708 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 free_pages_prepare+0x586/0xd80 mm/page_alloc.c:1451
 __free_contig_range_common+0x14f/0x250 mm/page_alloc.c:6897
 __free_contig_range mm/page_alloc.c:6942 [inline]
 free_pages_bulk+0xbd/0x200 mm/page_alloc.c:5257
 vm_area_free_pages+0xad/0x2b0 mm/vmalloc.c:3439
 vfree mm/vmalloc.c:3488 [inline]
 vfree+0x107/0x750 mm/vmalloc.c:3462
 kcov_put kernel/kcov.c:447 [inline]
 kcov_put kernel/kcov.c:443 [inline]
 kcov_close+0x34/0x60 kernel/kcov.c:554
 __fput+0x3ff/0xb50 fs/file_table.c:512
 task_work_run+0x150/0x240 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x951/0x2ae0 kernel/exit.c:1004
 do_group_exit+0xd5/0x2a0 kernel/exit.c:1147
 get_signal+0x1ec7/0x21e0 kernel/signal.c:3038
 arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
 exit_to_user_mode_loop+0x139/0x6f0 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:318 [inline]
 do_syscall_64+0x666/0x870 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff8880555fcd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880555fcd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880555fce00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff8880555fce80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880555fcf00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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