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BUG: KASAN: slab-use-after-free in __ethtool_get_link_ksettings+0x5e/0x170
Read of size 8 at addr ffff888114ff02f0 by task kworker/1:4/5680

CPU: 1 UID: 0 PID: 5680 Comm: kworker/1:4 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: events smc_ib_port_event_work
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 print_address_description+0x55/0x1e0
 print_report+0x58/0x70
 kasan_report+0x117/0x150
 __ethtool_get_link_ksettings+0x5e/0x170
 ib_get_eth_speed+0x180/0x7f0
 rxe_query_port+0x93/0x3d0
 ib_query_port+0x16e/0x830
 smc_ib_port_event_work+0x147/0x920
 process_scheduled_works+0xa8e/0x14e0
 worker_thread+0xa47/0xfb0
 kthread+0x389/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Allocated by task 17685:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kvmalloc_node_noprof+0x520/0x890
 alloc_netdev_mqs+0xa9/0x1260
 rtnl_create_link+0x321/0xd70
 rtnl_newlink_create+0x25f/0xb00
 rtnl_newlink+0x167f/0x1bd0
 rtnetlink_rcv_msg+0x802/0xc00
 netlink_rcv_skb+0x226/0x4a0
 netlink_unicast+0x7bb/0x940
 netlink_sendmsg+0x813/0xb40
 __sys_sendto+0x672/0x710
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 12:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x40/0x50
 __kasan_slab_free+0x5c/0x80
 kfree+0x1c5/0x640
 device_release+0xc4/0x1f0
 kobject_put+0x222/0x550
 netdev_run_todo+0xc77/0xde0
 default_device_exit_batch+0x966/0x9e0
 ops_undo_list+0x4b4/0x8d0
 cleanup_net+0x572/0x810
 process_scheduled_works+0xa8e/0x14e0
 worker_thread+0xa47/0xfb0
 kthread+0x389/0x470
 ret_from_fork+0x514/0xb70
 ret_from_fork_asm+0x1a/0x30

The buggy address belongs to the object at ffff888114ff0000
 which belongs to the cache kmalloc-cg-4k of size 4096
The buggy address is located 752 bytes inside of
 freed 4096-byte region [ffff888114ff0000, ffff888114ff1000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x114ff0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff888114ff1011
flags: 0x17ff00000000040(head|node=0|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 017ff00000000040 ffff88810005d500 dead000000000100 dead000000000122
raw: 0000000000000000 0000200000040004 00000000f5000000 ffff888114ff1011
head: 017ff00000000040 ffff88810005d500 dead000000000100 dead000000000122
head: 0000000000000000 0000200000040004 00000000f5000000 ffff888114ff1011
head: 017ff00000000003 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 9674, tgid 9674 (rm), ts 198961508843, free_ts 198181935997
 post_alloc_hook+0x22d/0x280
 get_page_from_freelist+0x23e2/0x2460
 __alloc_frozen_pages_noprof+0x18d/0x380
 allocate_slab+0x77/0x660
 refill_objects+0x336/0x3d0
 __pcs_replace_empty_main+0x320/0x720
 __kvmalloc_node_noprof+0x642/0x890
 seq_read_iter+0x1ea/0xca0
 proc_reg_read_iter+0x1b7/0x280
 vfs_read+0x595/0xa80
 ksys_read+0x150/0x270
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 9642 tgid 9637 stack trace:
 __free_frozen_pages+0xbc7/0xd30
 __folio_put+0x4b3/0x590
 __mptcp_clean_una+0x1b2/0xea0
 __mptcp_clean_una_wakeup+0x7f/0x340
 mptcp_release_cb+0x71f/0x900
 release_sock+0x206/0x260
 sk_stream_wait_memory+0x72b/0xf80
 mptcp_sendmsg+0x11fa/0x1d10
 sock_write_iter+0x330/0x4e0
 vfs_write+0x612/0xba0
 ksys_write+0x150/0x270
 do_syscall_64+0x174/0x580
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888114ff0180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888114ff0200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888114ff0280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff888114ff0300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888114ff0380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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