================================================================== BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:352 [inline] BUG: KASAN: slab-out-of-bounds in skb_copy_from_linear_data include/linux/skbuff.h:3414 [inline] BUG: KASAN: slab-out-of-bounds in __pskb_copy_fclone+0x2dd/0xeb0 net/core/skbuff.c:1395 Read of size 4294967282 at addr ffff8801c22300dc by task syz-executor4/4213 CPU: 0 PID: 4213 Comm: syz-executor4 Not tainted 4.20.0-rc1+ #141 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412 check_memory_region_inline mm/kasan/kasan.c:260 [inline] check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267 memcpy+0x23/0x50 mm/kasan/kasan.c:302 memcpy include/linux/string.h:352 [inline] skb_copy_from_linear_data include/linux/skbuff.h:3414 [inline] __pskb_copy_fclone+0x2dd/0xeb0 net/core/skbuff.c:1395 __pskb_copy include/linux/skbuff.h:1053 [inline] pskb_copy include/linux/skbuff.h:2897 [inline] skb_realloc_headroom+0xe7/0x120 net/core/skbuff.c:1539 ipip6_tunnel_xmit net/ipv6/sit.c:965 [inline] sit_tunnel_xmit+0xe1b/0x30d0 net/ipv6/sit.c:1029 __netdev_start_xmit include/linux/netdevice.h:4344 [inline] netdev_start_xmit include/linux/netdevice.h:4353 [inline] xmit_one net/core/dev.c:3252 [inline] dev_hard_start_xmit+0x295/0xc80 net/core/dev.c:3268 __dev_queue_xmit+0x2f71/0x3ad0 net/core/dev.c:3838 dev_queue_xmit+0x17/0x20 net/core/dev.c:3871 __bpf_tx_skb net/core/filter.c:2017 [inline] __bpf_redirect_common net/core/filter.c:2055 [inline] __bpf_redirect+0x5cf/0xb20 net/core/filter.c:2062 ____bpf_clone_redirect net/core/filter.c:2095 [inline] bpf_clone_redirect+0x2f6/0x490 net/core/filter.c:2067 bpf_prog_41f2bcae09cd4ac3+0x948/0x1000 Allocated by task 4213: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553 __do_kmalloc_node mm/slab.c:3684 [inline] __kmalloc_node_track_caller+0x50/0x70 mm/slab.c:3698 __kmalloc_reserve.isra.40+0x41/0xe0 net/core/skbuff.c:137 pskb_expand_head+0x230/0x10f0 net/core/skbuff.c:1460 skb_ensure_writable+0x3dd/0x640 net/core/skbuff.c:5073 __bpf_try_make_writable net/core/filter.c:1638 [inline] bpf_try_make_writable net/core/filter.c:1644 [inline] bpf_try_make_head_writable net/core/filter.c:1652 [inline] ____bpf_clone_redirect net/core/filter.c:2089 [inline] bpf_clone_redirect+0x14a/0x490 net/core/filter.c:2067 bpf_prog_41f2bcae09cd4ac3+0x948/0x1000 Freed by task 3176: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 skb_free_head+0x99/0xc0 net/core/skbuff.c:550 skb_release_data+0x6a4/0x880 net/core/skbuff.c:570 skb_release_all+0x4a/0x60 net/core/skbuff.c:627 __kfree_skb net/core/skbuff.c:641 [inline] consume_skb+0x1ae/0x570 net/core/skbuff.c:701 netlink_broadcast_filtered+0x6e6/0x1680 net/netlink/af_netlink.c:1512 netlink_broadcast net/netlink/af_netlink.c:1534 [inline] nlmsg_multicast include/net/netlink.h:734 [inline] nlmsg_notify+0xa0/0x1a0 net/netlink/af_netlink.c:2520 rtnl_notify+0xce/0xf0 net/core/rtnetlink.c:742 mpls_netconf_notify_devconf+0xb1/0x120 net/mpls/af_mpls.c:1201 mpls_dev_sysctl_register+0x212/0x2e0 net/mpls/af_mpls.c:1389 mpls_add_dev net/mpls/af_mpls.c:1436 [inline] mpls_dev_notify+0x338/0xba0 net/mpls/af_mpls.c:1562 notifier_call_chain+0x17e/0x380 kernel/notifier.c:93 __raw_notifier_call_chain kernel/notifier.c:394 [inline] raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1733 call_netdevice_notifiers net/core/dev.c:1751 [inline] register_netdevice+0xb98/0x11d0 net/core/dev.c:8558 tun_set_iff drivers/net/tun.c:2784 [inline] __tun_chr_ioctl+0x2b16/0x46e0 drivers/net/tun.c:3018 tun_chr_ioctl+0x2a/0x40 drivers/net/tun.c:3282 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0x1de/0x1790 fs/ioctl.c:696 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:713 __do_sys_ioctl fs/ioctl.c:720 [inline] __se_sys_ioctl fs/ioctl.c:718 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8801c2230080 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 92 bytes inside of 512-byte region [ffff8801c2230080, ffff8801c2230280) The buggy address belongs to the page: page:ffffea0007088c00 count:1 mapcount:0 mapping:ffff8801da800940 index:0x0 flags: 0x2fffc0000000200(slab) raw: 02fffc0000000200 ffffea0006f3ac48 ffffea00074e3108 ffff8801da800940 raw: 0000000000000000 ffff8801c2230080 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c2230180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8801c2230200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8801c2230280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8801c2230300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8801c2230380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================