BUG: KASAN: use-after-free in do_shrink_slab+0xbe6/0xce0 mm/vmscan.c:785 Read of size 8 at addr ffff88801fd935b8 by task kswapd1/127 CPU: 3 PID: 127 Comm: kswapd1 Not tainted 6.1.0-rc1-syzkaller-00002-gbbb8ceb5e242 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15e/0x461 mm/kasan/report.c:395 kasan_report+0xbb/0x1f0 mm/kasan/report.c:495 do_shrink_slab+0xbe6/0xce0 mm/vmscan.c:785 shrink_slab+0x175/0x660 mm/vmscan.c:1002 shrink_node_memcgs mm/vmscan.c:6076 [inline] shrink_node+0x93d/0x1f30 mm/vmscan.c:6105 kswapd_shrink_node mm/vmscan.c:6894 [inline] balance_pgdat+0x8f5/0x1530 mm/vmscan.c:7084 kswapd+0x707/0xfc0 mm/vmscan.c:7344 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Allocated by task 3908: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 kasan_set_track+0x21/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:371 [inline] ____kasan_kmalloc mm/kasan/common.c:330 [inline] __kasan_kmalloc+0x9f/0xb0 mm/kasan/common.c:380 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:955 [inline] __kmalloc+0x54/0xc0 mm/slab_common.c:968 kmalloc include/linux/slab.h:581 [inline] kzalloc include/linux/slab.h:712 [inline] ops_init+0xfb/0x470 net/core/net_namespace.c:124 setup_net+0x5d1/0xc50 net/core/net_namespace.c:325 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x306e/0x7190 kernel/fork.c:2256 kernel_clone+0xe7/0x980 kernel/fork.c:2671 __do_sys_clone+0xba/0x100 kernel/fork.c:2812 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 3908: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 kasan_set_track+0x21/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:511 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x13b/0x1a0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:177 [inline] __cache_free mm/slab.c:3389 [inline] __do_kmem_cache_free mm/slab.c:3585 [inline] __kmem_cache_free+0xc9/0x3a0 mm/slab.c:3592 ops_init+0xcd/0x470 net/core/net_namespace.c:139 setup_net+0x5d1/0xc50 net/core/net_namespace.c:325 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x306e/0x7190 kernel/fork.c:2256 kernel_clone+0xe7/0x980 kernel/fork.c:2671 __do_sys_clone+0xba/0x100 kernel/fork.c:2812 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff88801fd93000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1464 bytes inside of 2048-byte region [ffff88801fd93000, ffff88801fd93800) The buggy address belongs to the physical page: page:ffffea00007f64c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1fd93 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffffea0000962ec8 ffffea00008aad08 ffff888011840800 raw: 0000000000000000 ffff88801fd93000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2c2220(__GFP_HIGH|__GFP_ATOMIC|__GFP_NOWARN|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_THISNODE), pid 3709, tgid 3709 (syz-executor.1), ts 195258566942, free_ts 195136922318 prep_new_page mm/page_alloc.c:2538 [inline] get_page_from_freelist+0x10b5/0x2d50 mm/page_alloc.c:4287 __alloc_pages_slowpath.constprop.0+0x36b/0x23d0 mm/page_alloc.c:5088 __alloc_pages+0x4a6/0x5a0 mm/page_alloc.c:5567 __alloc_pages_node include/linux/gfp.h:223 [inline] kmem_getpages mm/slab.c:1363 [inline] cache_grow_begin+0x75/0x360 mm/slab.c:2570 cache_alloc_refill+0x27f/0x380 mm/slab.c:2943 ____cache_alloc mm/slab.c:3019 [inline] ____cache_alloc mm/slab.c:3002 [inline] __do_cache_alloc mm/slab.c:3202 [inline] slab_alloc_node mm/slab.c:3250 [inline] __kmem_cache_alloc_node+0x442/0x500 mm/slab.c:3549 __do_kmalloc_node mm/slab_common.c:954 [inline] __kmalloc_node_track_caller+0x45/0xc0 mm/slab_common.c:975 kmalloc_reserve net/core/skbuff.c:437 [inline] __alloc_skb+0xd9/0x2f0 net/core/skbuff.c:509 alloc_skb include/linux/skbuff.h:1267 [inline] nlmsg_new include/net/netlink.h:964 [inline] inet6_ifinfo_notify+0x72/0x150 net/ipv6/addrconf.c:6047 addrconf_notify+0x4a4/0x1c10 net/ipv6/addrconf.c:3657 notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1945 call_netdevice_notifiers_extack net/core/dev.c:1983 [inline] call_netdevice_notifiers net/core/dev.c:1997 [inline] __dev_notify_flags+0x110/0x2b0 net/core/dev.c:8577 rtnl_configure_link+0x16b/0x240 net/core/rtnetlink.c:3200 rtnl_newlink_create net/core/rtnetlink.c:3372 [inline] __rtnl_newlink+0x10b8/0x17e0 net/core/rtnetlink.c:3581 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3594 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1458 [inline] free_pcp_prepare+0x65c/0xd90 mm/page_alloc.c:1508 free_unref_page_prepare mm/page_alloc.c:3386 [inline] free_unref_page+0x19/0x4d0 mm/page_alloc.c:3482 slab_destroy mm/slab.c:1615 [inline] slabs_destroy+0x85/0xc0 mm/slab.c:1635 cache_flusharray mm/slab.c:3360 [inline] ___cache_free+0x2a8/0x3d0 mm/slab.c:3423 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x4f/0x1a0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x5f/0x80 mm/kasan/common.c:302 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slab.h:737 [inline] slab_alloc_node mm/slab.c:3257 [inline] __kmem_cache_alloc_node+0x25e/0x500 mm/slab.c:3549 kmalloc_trace+0x22/0x60 mm/slab_common.c:1046 kmalloc include/linux/slab.h:576 [inline] kzalloc include/linux/slab.h:712 [inline] ref_tracker_alloc+0x14c/0x550 lib/ref_tracker.c:85 __netdev_tracker_alloc include/linux/netdevice.h:3993 [inline] netdev_hold include/linux/netdevice.h:4022 [inline] netdev_hold include/linux/netdevice.h:4017 [inline] netdev_queue_add_kobject net/core/net-sysfs.c:1663 [inline] netdev_queue_update_kobjects+0x1a7/0x4e0 net/core/net-sysfs.c:1718 register_queue_kobjects net/core/net-sysfs.c:1779 [inline] netdev_register_kobject+0x330/0x400 net/core/net-sysfs.c:2019 register_netdevice+0xd95/0x1670 net/core/dev.c:10053 veth_newlink+0x338/0x990 drivers/net/veth.c:1764 rtnl_newlink_create net/core/rtnetlink.c:3364 [inline] __rtnl_newlink+0x1087/0x17e0 net/core/rtnetlink.c:3581 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3594 Memory state around the buggy address: ffff88801fd93480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801fd93500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88801fd93580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801fd93600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801fd93680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================