==================================================================
BUG: KASAN: slab-use-after-free in __ethtool_get_link_ksettings+0x6e/0x190 net/ethtool/ioctl.c:443
Read of size 8 at addr ffff88802a20e2e8 by task kworker/0:2/975

CPU: 0 UID: 0 PID: 975 Comm: kworker/0:2 Not tainted 6.15.0-rc2-syzkaller-00258-g750d0ac001e8 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events smc_ib_port_event_work
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0x16e/0x5b0 mm/kasan/report.c:521
 kasan_report+0x143/0x180 mm/kasan/report.c:634
 __ethtool_get_link_ksettings+0x6e/0x190 net/ethtool/ioctl.c:443
 ib_get_eth_speed+0x170/0x850 drivers/infiniband/core/verbs.c:1996
 rxe_query_port+0x95/0x3b0 drivers/infiniband/sw/rxe/rxe_verbs.c:62
 __ib_query_port drivers/infiniband/core/device.c:2109 [inline]
 ib_query_port+0x169/0x7e0 drivers/infiniband/core/device.c:2141
 smc_ib_remember_port_attr net/smc/smc_ib.c:364 [inline]
 smc_ib_port_event_work+0x151/0xac0 net/smc/smc_ib.c:388
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd50 kernel/workqueue.c:3400
 kthread+0x7b7/0x940 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 10045:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x9d/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4341 [inline]
 __kvmalloc_node_noprof+0x329/0x5a0 mm/slub.c:5026
 alloc_netdev_mqs+0xa4/0x1210 net/core/dev.c:11616
 rtnl_create_link+0x2f9/0xc90 net/core/rtnetlink.c:3641
 rtnl_newlink_create+0x2f2/0xcb0 net/core/rtnetlink.c:3823
 __rtnl_newlink net/core/rtnetlink.c:3950 [inline]
 rtnl_newlink+0x18b0/0x1fe0 net/core/rtnetlink.c:4065
 rtnetlink_rcv_msg+0x80f/0xd70 net/core/rtnetlink.c:6955
 netlink_rcv_skb+0x208/0x480 net/netlink/af_netlink.c:2534
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x7f8/0x9a0 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x8c3/0xcd0 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:727
 __sys_sendto+0x365/0x4c0 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+0xf3/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 53:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2398 [inline]
 slab_free mm/slub.c:4656 [inline]
 kfree+0x198/0x430 mm/slub.c:4855
 device_release+0x99/0x1c0 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+0x22f/0x480 lib/kobject.c:737
 netdev_run_todo+0xd9f/0xf30 net/core/dev.c:11317
 default_device_exit_batch+0x804/0x880 net/core/dev.c:12539
 ops_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x8af/0xd60 net/core/net_namespace.c:654
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd50 kernel/workqueue.c:3400
 kthread+0x7b7/0x940 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff88802a20e000
 which belongs to the cache kmalloc-cg-4k of size 4096
The buggy address is located 744 bytes inside of
 freed 4096-byte region [ffff88802a20e000, ffff88802a20f000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2a208
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b04b500 ffffea0000a87600 dead000000000002
raw: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b04b500 ffffea0000a87600 dead000000000002
head: 0000000000000000 0000000000040004 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0000a88201 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 5215, tgid 5215 (udevd), ts 58120212358, free_ts 58100181464
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1718
 prep_new_page mm/page_alloc.c:1726 [inline]
 get_page_from_freelist+0x360a/0x37a0 mm/page_alloc.c:3700
 __alloc_frozen_pages_noprof+0x211/0x5b0 mm/page_alloc.c:4982
 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2468 [inline]
 allocate_slab+0x8f/0x3b0 mm/slub.c:2632
 new_slab mm/slub.c:2686 [inline]
 ___slab_alloc+0xc3b/0x1500 mm/slub.c:3872
 __slab_alloc+0x58/0xa0 mm/slub.c:3962
 __slab_alloc_node mm/slub.c:4037 [inline]
 slab_alloc_node mm/slub.c:4198 [inline]
 __do_kmalloc_node mm/slub.c:4340 [inline]
 __kvmalloc_node_noprof+0x3f4/0x5a0 mm/slub.c:5026
 seq_buf_alloc fs/seq_file.c:38 [inline]
 seq_read_iter+0x20b/0xda0 fs/seq_file.c:210
 new_sync_read fs/read_write.c:489 [inline]
 vfs_read+0x9a0/0xb90 fs/read_write.c:570
 ksys_read+0x19d/0x2d0 fs/read_write.c:713
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 5214 tgid 5214 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0xde8/0x10a0 mm/page_alloc.c:2725
 discard_slab mm/slub.c:2730 [inline]
 __put_partials+0x160/0x1c0 mm/slub.c:3199
 put_cpu_partial+0x17e/0x250 mm/slub.c:3274
 __slab_free+0x294/0x390 mm/slub.c:4526
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4161 [inline]
 slab_alloc_node mm/slub.c:4210 [inline]
 kmem_cache_alloc_noprof+0x1e1/0x390 mm/slub.c:4217
 getname_flags+0xb7/0x530 fs/namei.c:146
 getname include/linux/fs.h:2852 [inline]
 getname_maybe_null include/linux/fs.h:2859 [inline]
 vfs_fstatat+0x43/0x150 fs/stat.c:363
 __do_sys_newfstatat fs/stat.c:532 [inline]
 __se_sys_newfstatat fs/stat.c:526 [inline]
 __x64_sys_newfstatat+0x11f/0x1a0 fs/stat.c:526
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88802a20e180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a20e200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802a20e280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                          ^
 ffff88802a20e300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802a20e380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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