syzbot

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BUG: KASAN: slab-use-after-free in __ethtool_get_link_ksettings+0x6e/0x190 net/ethtool/ioctl.c:442
Read of size 8 at addr ffff888000974308 by task kworker/0:4/5385

CPU: 0 UID: 0 PID: 5385 Comm: kworker/0:4 Not tainted 6.12.0-rc6-syzkaller-00099-g7758b206117d #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
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:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 __ethtool_get_link_ksettings+0x6e/0x190 net/ethtool/ioctl.c:442
 ib_get_eth_speed+0x160/0x800 drivers/infiniband/core/verbs.c:1996
 rxe_query_port+0x76/0x260 drivers/infiniband/sw/rxe/rxe_verbs.c:55
 __ib_query_port drivers/infiniband/core/device.c:2111 [inline]
 ib_query_port+0x166/0x7d0 drivers/infiniband/core/device.c:2143
 smc_ib_remember_port_attr net/smc/smc_ib.c:364 [inline]
 smc_ib_port_event_work+0x14e/0xa50 net/smc/smc_ib.c:388
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 7361:
 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+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:257 [inline]
 __do_kmalloc_node mm/slub.c:4264 [inline]
 __kmalloc_node_noprof+0x22a/0x440 mm/slub.c:4270
 __kvmalloc_node_noprof+0x72/0x190 mm/util.c:658
 alloc_netdev_mqs+0x9b/0x1000 net/core/dev.c:11101
 rtnl_create_link+0x2f9/0xc20 net/core/rtnetlink.c:3403
 rtnl_newlink_create net/core/rtnetlink.c:3529 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3759 [inline]
 rtnl_newlink+0x1423/0x20a0 net/core/rtnetlink.c:3772
 rtnetlink_rcv_msg+0x73f/0xcf0 net/core/rtnetlink.c:6675
 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2551
 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
 netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1357
 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:729 [inline]
 __sock_sendmsg+0x221/0x270 net/socket.c:744
 __sys_sendto+0x39b/0x4f0 net/socket.c:2214
 __do_sys_sendto net/socket.c:2226 [inline]
 __se_sys_sendto net/socket.c:2222 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2222
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 27:
 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:579
 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:230 [inline]
 slab_free_hook mm/slub.c:2342 [inline]
 slab_free mm/slub.c:4579 [inline]
 kfree+0x1a0/0x440 mm/slub.c:4727
 device_release+0x99/0x1c0
 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+0xe79/0x1000 net/core/dev.c:10820
 default_device_exit_batch+0xa24/0xaa0 net/core/dev.c:11953
 ops_exit_list net/core/net_namespace.c:178 [inline]
 cleanup_net+0x89d/0xcc0 net/core/net_namespace.c:626
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310
 worker_thread+0x870/0xd30 kernel/workqueue.c:3391
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

The buggy address belongs to the object at ffff888000974000
 which belongs to the cache kmalloc-cg-4k of size 4096
The buggy address is located 776 bytes inside of
 freed 4096-byte region [ffff888000974000, ffff888000975000)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x970
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x7ff00000000040(head|node=0|zone=0|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 007ff00000000040 ffff88801ac4f500 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000040004 00000001f5000000 0000000000000000
head: 007ff00000000040 ffff88801ac4f500 dead000000000100 dead000000000122
head: 0000000000000000 0000000000040004 00000001f5000000 0000000000000000
head: 007ff00000000003 ffffea0000025c01 ffffffffffffffff 0000000000000000
head: ffff888000000008 0000000000000000 00000000ffffffff 0000000000000000
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 4739, tgid 4739 (udevd), ts 26544987479, free_ts 26487230692
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1545 [inline]
 get_page_from_freelist+0x303f/0x3190 mm/page_alloc.c:3457
 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4733
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 alloc_slab_page+0x6a/0x140 mm/slub.c:2412
 allocate_slab+0x5a/0x2f0 mm/slub.c:2578
 new_slab mm/slub.c:2631 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3818
 __slab_alloc+0x58/0xa0 mm/slub.c:3908
 __slab_alloc_node mm/slub.c:3961 [inline]
 slab_alloc_node mm/slub.c:4122 [inline]
 __do_kmalloc_node mm/slub.c:4263 [inline]
 __kmalloc_node_noprof+0x286/0x440 mm/slub.c:4270
 __kvmalloc_node_noprof+0x72/0x190 mm/util.c:658
 seq_buf_alloc fs/seq_file.c:38 [inline]
 seq_read_iter+0x20c/0xd70 fs/seq_file.c:210
 new_sync_read fs/read_write.c:488 [inline]
 vfs_read+0x991/0xb70 fs/read_write.c:569
 ksys_read+0x183/0x2b0 fs/read_write.c:712
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 4749 tgid 4749 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1108 [inline]
 free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638
 discard_slab mm/slub.c:2677 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:3145
 put_cpu_partial+0x17c/0x250 mm/slub.c:3220
 __slab_free+0x2ea/0x3d0 mm/slub.c:4449
 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:247 [inline]
 slab_post_alloc_hook mm/slub.c:4085 [inline]
 slab_alloc_node mm/slub.c:4134 [inline]
 kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4141
 getname_flags+0xb7/0x540 fs/namei.c:139
 do_sys_openat2+0xd2/0x1d0 fs/open.c:1409
 do_sys_open fs/open.c:1430 [inline]
 __do_sys_openat fs/open.c:1446 [inline]
 __se_sys_openat fs/open.c:1441 [inline]
 __x64_sys_openat+0x247/0x2a0 fs/open.c:1441
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888000974200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888000974280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888000974300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff888000974380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888000974400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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