================================================================== BUG: KASAN: slab-use-after-free in __ethtool_get_link_ksettings+0x190/0x1c0 net/ethtool/ioctl.c:443 Read of size 8 at addr ffff8880262762f0 by task kworker/2:0/24 CPU: 2 UID: 0 PID: 24 Comm: kworker/2:0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Workqueue: events smc_ib_port_event_work Call Trace: __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+0x156/0x4c9 mm/kasan/report.c:482 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595 __ethtool_get_link_ksettings+0x190/0x1c0 net/ethtool/ioctl.c:443 __ethtool_get_link_ksettings+0x144/0x1c0 net/ethtool/ioctl.c:450 ib_get_eth_speed+0x13a/0xb40 drivers/infiniband/core/verbs.c:2054 rxe_query_port+0x12a/0x330 drivers/infiniband/sw/rxe/rxe_verbs.c:62 __ib_query_port drivers/infiniband/core/device.c:2120 [inline] ib_query_port drivers/infiniband/core/device.c:2152 [inline] ib_query_port+0x441/0x8a0 drivers/infiniband/core/device.c:2142 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+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 5994: 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:5238 [inline] __kvmalloc_node_noprof+0x360/0xa00 mm/slub.c:6730 alloc_netdev_mqs+0xd7/0x14f0 net/core/dev.c:12030 rtnl_create_link+0xc13/0xf80 net/core/rtnetlink.c:3648 rtnl_newlink_create net/core/rtnetlink.c:3830 [inline] __rtnl_newlink net/core/rtnetlink.c:3957 [inline] rtnl_newlink+0x13b8/0x2380 net/core/rtnetlink.c:4072 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6958 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x5aa/0x870 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] __sys_sendto+0x468/0x4b0 net/socket.c:2206 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 6100: 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:2692 [inline] slab_free mm/slub.c:6143 [inline] kfree+0x1f6/0x6b0 mm/slub.c:6461 device_release+0xa4/0x240 drivers/base/core.c:2565 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+0x817/0x12c0 net/core/dev.c:11731 default_device_exit_batch+0x94b/0xc60 net/core/dev.c:13070 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:704 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x754/0xd80 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 ffff888026276000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 752 bytes inside of freed 4096-byte region [ffff888026276000, ffff888026277000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x26270 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88803934e481 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b880280 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800040004 00000000f5000000 ffff88803934e481 head: 00fff00000000040 ffff88801b880280 dead000000000100 dead000000000122 head: 0000000000000000 0000000800040004 00000000f5000000 ffff88803934e481 head: 00fff00000000003 ffffea0000989c01 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 5997, tgid 5997 (syz-executor), ts 374106964886, free_ts 28740690407 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x153/0x170 mm/page_alloc.c:1889 prep_new_page mm/page_alloc.c:1897 [inline] get_page_from_freelist+0x111d/0x3140 mm/page_alloc.c:3962 __alloc_frozen_pages_noprof+0x27c/0x2ba0 mm/page_alloc.c:5250 alloc_slab_page mm/slub.c:3269 [inline] allocate_slab mm/slub.c:3458 [inline] new_slab+0xa6/0x6d0 mm/slub.c:3516 refill_objects+0x26b/0x400 mm/slub.c:7153 refill_sheaf mm/slub.c:2818 [inline] alloc_full_sheaf mm/slub.c:2839 [inline] __pcs_replace_empty_main+0x19f/0x600 mm/slub.c:4602 alloc_from_pcs mm/slub.c:4695 [inline] slab_alloc_node mm/slub.c:4829 [inline] __kmalloc_cache_noprof+0x493/0x6f0 mm/slub.c:5353 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] snmp6_alloc_dev net/ipv6/addrconf.c:361 [inline] ipv6_add_dev+0x670/0x1520 net/ipv6/addrconf.c:412 addrconf_notify+0x563/0x19c0 net/ipv6/addrconf.c:3654 notifier_call_chain+0x99/0x420 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x110 net/core/dev.c:2249 call_netdevice_notifiers_extack net/core/dev.c:2287 [inline] call_netdevice_notifiers net/core/dev.c:2301 [inline] register_netdevice+0x16e6/0x2210 net/core/dev.c:11462 macvlan_common_newlink+0xf70/0x18b0 drivers/net/macvlan.c:1546 rtnl_newlink_create net/core/rtnetlink.c:3840 [inline] __rtnl_newlink net/core/rtnetlink.c:3957 [inline] rtnl_newlink+0x1494/0x2380 net/core/rtnetlink.c:4072 rtnetlink_rcv_msg+0x95e/0xe90 net/core/rtnetlink.c:6958 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2550 page last free pid 5338 tgid 5338 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0x7e1/0x10d0 mm/page_alloc.c:2978 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4515 [inline] slab_alloc_node mm/slub.c:4844 [inline] kmem_cache_alloc_node_noprof+0x25a/0x6f0 mm/slub.c:4896 __alloc_skb+0x140/0x710 net/core/skbuff.c:702 alloc_skb include/linux/skbuff.h:1383 [inline] netlink_alloc_large_skb+0x69/0x150 net/netlink/af_netlink.c:1184 netlink_sendmsg+0x680/0xda0 net/netlink/af_netlink.c:1869 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0x9e1/0xb70 net/socket.c:2592 ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646 __sys_sendmsg+0x170/0x220 net/socket.c:2678 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888026276180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888026276200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888026276280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888026276300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888026276380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================