Linux Kernel up to 5.12.8 mld_newpack denial of service

Summaryinfo

A vulnerability was found in Linux Kernel up to 5.12.8. It has been classified as critical. The affected element is the function mld_newpack. This manipulation causes denial of service. This vulnerability is tracked as CVE-2021-47146. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.12.8. It has been declared as critical. Affected by this vulnerability is the function mld_newpack. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: mld: fix panic in mld_newpack() mld_newpack() doesn't allow to allocate high order page, only order-0 allocation is allowed. If headroom size is too large, a kernel panic could occur in skb_put(). Test commands: 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 a a 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 a a 2001:db8:0::2/64 dev veth1 for i in {1..99} do let A=$i-1 ip netns exec A ip link add ip6gre$i type ip6gre \ local 2001:db8:$A::1 remote 2001:db8:$A::2 encaplimit 100 ip netns exec A ip -6 a a 2001:db8:$i::1/64 dev ip6gre$i ip netns exec A ip link set 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 a a 2001:db8:$i::2/64 dev ip6gre$i ip netns exec B ip link set ip6gre$i up done Splat looks like: kernel BUG at net/core/skbuff.c:110! invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI CPU: 0 PID: 7 Comm: kworker/0:1 Not tainted 5.12.0+ #891 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:skb_panic+0x15d/0x15f Code: 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 54 24 a6 26 f9 ff 0b 48 8b 6c 24 20 89 34 24 e8 4a 4e 92 fe 8b 34 24 48 c7 c1 20 RSP: 0018:ffff88810091f820 EFLAGS: 00010282 RAX: 0000000000000089 RBX: ffff8881086e9000 RCX: 0000000000000000 RDX: 0000000000000089 RSI: 0000000000000008 RDI: ffffed1020123efb RBP: ffff888005f6eac0 R08: ffffed1022fc0031 R09: ffffed1022fc0031 R10: ffff888117e00187 R11: ffffed1022fc0030 R12: 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 Call Trace: ? 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 Allowing high order page allocation could fix this problem.

The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2021-47146 since 03/04/2024. Technical details are known, but no exploit is available.

Upgrading to version 4.4.271, 4.9.271, 4.14.235, 4.19.193, 5.4.124, 5.10.42, 5.12.9 or 5.13 eliminates this vulnerability. Applying the patch 0e35b7457b7b/17728616a4c8/221142038f36/4b77ad909706/37d697759958/beb39adb150f/a76fb9ba5452/020ef930b826 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2024-0699). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• EMC Avamar
• Dell NetWorker
• Open Source Linux Kernel
• IBM Spectrum Protect Plus

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.4.270
• 4.9.270
• 4.14.234
• 4.19.192
• 5.4.123
• 5.10.0
• 5.10.1
• 5.10.2
• 5.10.3
• 5.10.4
• 5.10.5
• 5.10.6
• 5.10.7
• 5.10.8
• 5.10.9
• 5.10.10
• 5.10.11
• 5.10.12
• 5.10.13
• 5.10.14
• 5.10.15
• 5.10.16
• 5.10.17
• 5.10.18
• 5.10.19
• 5.10.20
• 5.10.21
• 5.10.22
• 5.10.23
• 5.10.24
• 5.10.25
• 5.10.26
• 5.10.27
• 5.10.28
• 5.10.29
• 5.10.30
• 5.10.31
• 5.10.32
• 5.10.33
• 5.10.34
• 5.10.35
• 5.10.36
• 5.10.37
• 5.10.38
• 5.10.39
• 5.10.40
• 5.10.41
• 5.12.0
• 5.12.1
• 5.12.2
• 5.12.3
• 5.12.4
• 5.12.5
• 5.12.6
• 5.12.7
• 5.12.8

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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