Linux/Unix 主机中安装的一个或多个程序包受到一个漏洞影响，而供应商没有提供补丁程序。

  - mld修复 mld_newpack() 中的错误 mld_newpack() 不允许分配高阶页仅允许 order-0 分配。如果余量过大skb_put() 中可发生内核错误。测试命令ip netns del A ip netns del B ip netns add A ip netns add B ip link add veth0 type veth Peer name veth1 ip link set veth0 netns A ip link set veth1 netns B ip netns exec A ip link set lo up ip netns exec A ip link set veth0 up ip netns exec A ip -6 aa 2001:db8:0::1/64 dev veth0 ip netns exec B ip link set lo up ip netns exec B ip link set veth1 up ip netns exec B ip -6 aa 2001:db8:0::2/64 dev veth1 for i in {1..99} do 让 A=$i-1 ip netns exec A ip link add ip6gre$i 类型 ip6gre \ local 2001:db8 :$A::1 remote 2001:db8:$A::2 encaplimit 100 ip netns exec A ip -6 aa 2001:db8:$i::1/64 dev ip6gre$i ip netns exec A ip 链接设置 ip6gre$i up ip netns exec B ip link add ip6gre$i type ip6gre \ local 2001:db8:$A::2 remote 2001:db8:$A::1 encaplimit 100 ip netns exec B ip -6 aa 2001:db8:$i::2/64 dev ip6gre$i ip netns exec B ip link set ip6gre$i up完成 Splat 看起来像net/core/skbuff.c:110! 的内核缺陷无效 opcode0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI CPU: 0 PID: 7 Comm: kworker/0:1 未受感染 5.12.0+ #891 Workqueue
    ipv6_addrconf addrconf_dad_work RIP0010:skb_panic+0x15d/0x15f 代码92 fe 4c 8b 4c 24 10 53 8b 4d 70 45 89 e0 48 c7 c7 00 ae 79 83 41 57 41 56 41 55 48 8b ae 79 83 41 56 41 55 48 5 ae 41 55 48 ff 4 26 <0f> f42 0b 48 8b 6c 24 20 89 34 24 e8 4a 4e 92 fe 8b 34 24 48 c7 c1 20 RSP0018:ffff88810091f820 EFLAGS00010282 RAX: 0000000000000089 RBX
    ffff8881086e9000 RCX: 0000000000000000 RDX: 0000000000000089 RSI: 0000000000000008 RDI: ffffed1020123efb RBP: ffff888005f6eac0 R08: ffffed1022fc0031 R09: ffffed1022fc0031 R10: ffff888117e00187 R11:
     R12ffffed1022fc0030  : 0000000000000028 R13: ffff888008284eb0 R14: 0000000000000ed8 R15: 0000000000000ec0 FS: 0000000000000000(0000) GS:ffff888117c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8b801c5640 CR3: 0000000033c2c006 CR4: 00000000003706f0 DR0
    0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 调用跟踪ip6_mc_hdr.isra.26.constprop.46+0x12a/0x600 ip6_mc_hdr.isra.26.constprop.46+0x12a/0x600 skb_put.cold.104+0x22/0x22 ip6_mc_hdr.isra.26.constprop.46+0x12a/0x600 rcu_read_lock_sched_held+0x91/0xc0 mld_newpack+0x398/0x8f0 ? ip6_mc_hdr.isra.26.constprop.46+0x600/0x600 lock_contended+0xc40/0xc40 add_grhead.isra.33+0x280/0x380 add_grec+0x5ca/0xff0 ? mld_sendpack+0xf40/0xf40 lock_downgrade+0x690/0x690 mld_send_initial_cr.part.34+0xb9/0x180 ipv6_mc_dad_complete+0x15d/0x1b0 addrconf_dad_completed+0x8d2/0xbb0 ? lock_downgrade+0x690/0x690 ? addrconf_rs_timer+0x660/0x660 ? addrconf_dad_work+0x73c/0x10e0 addrconf_dad_work+0x73c/0x10e0 允许高阶页面分配可修复此问题。
    (CVE-2021-47146)

请注意，Nessus 依赖供应商报告的程序包是否存在进行判断。

检测

Linux Distros 未修补的漏洞：CVE-2021-47146

medium Nessus 插件 ID 224434

版本 1.19