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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+0x230/0x250 net/ethtool/ioctl.c:463
Read of size 1 at addr ffff888042ab2e09 by task kworker/1:12/28385

CPU: 1 UID: 0 PID: 28385 Comm: kworker/1:12 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events smc_ib_port_event_work
Call Trace:
 <TASK>
 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+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 kthread+0x388/0x470 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
 </TASK>

Allocated by task 27681:
 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:5362 [inline]
 __kvmalloc_node_noprof+0x53f/0x860 mm/slub.c:6933
 alloc_netdev_mqs+0xa9/0x12b0 net/core/dev.c:12048
 rtnl_create_link+0x321/0xd70 net/core/rtnetlink.c:3721
 rtnl_newlink_create+0x25f/0xb00 net/core/rtnetlink.c:3903
 __rtnl_newlink net/core/rtnetlink.c:4044 [inline]
 rtnl_newlink+0x167f/0x1bd0 net/core/rtnetlink.c:4159
 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7076
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7bb/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:775
 __sock_sendmsg net/socket.c:790 [inline]
 __sys_sendto+0x408/0x5a0 net/socket.c:2252
 __do_sys_sendto net/socket.c:2259 [inline]
 __se_sys_sendto net/socket.c:2255 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2255
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 3116:
 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:2705 [inline]
 slab_free mm/slub.c:6405 [inline]
 kfree+0x1c5/0x640 mm/slub.c:6720
 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+0xf56/0x10d0 net/core/dev.c:11749
 rtnl_unlock net/core/rtnetlink.c:157 [inline]
 rtnl_net_unlock include/linux/rtnetlink.h:135 [inline]
 rtnl_dellink+0x68f/0x810 net/core/rtnetlink.c:3651
 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7076
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x7bb/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:775
 __sock_sendmsg net/socket.c:790 [inline]
 ____sys_sendmsg+0x54e/0x850 net/socket.c:2684
 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2738
 __sys_sendmsg net/socket.c:2770 [inline]
 __do_sys_sendmsg net/socket.c:2775 [inline]
 __se_sys_sendmsg net/socket.c:2773 [inline]
 __x64_sys_sendmsg+0x1b1/0x290 net/socket.c:2773
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888042ab2000
 which belongs to the cache kmalloc-cg-4k of size 4096
The buggy address is located 3593 bytes inside of
 freed 4096-byte region [ffff888042ab2000, ffff888042ab3000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888042ab4000 pfn:0x42ab0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff888042ab1011
flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000240 ffff88801b01b500 ffffea000150e610 ffffea0001f3f610
raw: ffff888042ab4000 0000200000040002 00000000f5000000 ffff888042ab1011
head: 00fff00000000240 ffff88801b01b500 ffffea000150e610 ffffea0001f3f610
head: ffff888042ab4000 0000200000040002 00000000f5000000 ffff888042ab1011
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 27681, tgid 27681 (syz-executor), ts 607149991722, free_ts 606971815316
 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+0x21fa/0x2270 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304
 alloc_slab_page mm/slub.c:3294 [inline]
 allocate_slab+0x79/0x5e0 mm/slub.c:3408
 new_slab mm/slub.c:3454 [inline]
 refill_objects+0x2d5/0x350 mm/slub.c:7338
 refill_sheaf mm/slub.c:2832 [inline]
 __pcs_replace_empty_main+0x2bf/0x6b0 mm/slub.c:4703
 alloc_from_pcs mm/slub.c:4801 [inline]
 slab_alloc_node mm/slub.c:4933 [inline]
 __kmalloc_cache_noprof+0x3a7/0x660 mm/slub.c:5511
 _kmalloc_noprof include/linux/slab.h:969 [inline]
 _kzalloc_noprof include/linux/slab.h:1290 [inline]
 snmp6_alloc_dev net/ipv6/addrconf.c:362 [inline]
 ipv6_add_dev+0x6aa/0x13a0 net/ipv6/addrconf.c:413
 addrconf_notify+0x771/0x1050 net/ipv6/addrconf.c:3685
 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2288 [inline]
 call_netdevice_notifiers net/core/dev.c:2302 [inline]
 register_netdevice+0x18a4/0x1eb0 net/core/dev.c:11478
 veth_newlink+0x676/0xb70 drivers/net/veth.c:1892
 rtnl_newlink_create+0x310/0xb00 net/core/rtnetlink.c:3913
 __rtnl_newlink net/core/rtnetlink.c:4044 [inline]
 rtnl_newlink+0x167f/0x1bd0 net/core/rtnetlink.c:4159
 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7076
 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2556
page last free pid 27903 tgid 27902 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 __free_pages_ok+0xad4/0xbd0 mm/page_alloc.c:1584
 bpf_check+0x3ee5/0x5310 kernel/bpf/verifier.c:20004
 bpf_prog_load+0x1577/0x1c00 kernel/bpf/syscall.c:3197
 __sys_bpf+0xd0d/0xd90 kernel/bpf/syscall.c:6418
 __do_sys_bpf kernel/bpf/syscall.c:6537 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6534 [inline]
 __x64_sys_bpf+0xba/0xd0 kernel/bpf/syscall.c:6534
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888042ab2d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888042ab2d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888042ab2e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff888042ab2e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888042ab2f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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