CVE-2024-39490 ipv6: sr: fix missing sk_buff release in seg6_input_core

2024-07-1007:14:09

Linux

github.com

linux kernel vulnerabilities

ipv6

seg6_input_core

memory leak

network packet

patch

AI Score

6.9

Confidence

Low

SSVC

Exploitation

none

Automatable

Technical Impact

partial

JSON

In the Linux kernel, the following vulnerability has been resolved:

ipv6: sr: fix missing sk_buff release in seg6_input_core

The seg6_input() function is responsible for adding the SRH into a
packet, delegating the operation to the seg6_input_core(). This function
uses the skb_cow_head() to ensure that there is sufficient headroom in
the sk_buff for accommodating the link-layer header.
In the event that the skb_cow_header() function fails, the
seg6_input_core() catches the error but it does not release the sk_buff,
which will result in a memory leak.

This issue was introduced in commit af3b5158b89d (“ipv6: sr: fix BUG due
to headroom too small after SRH push”) and persists even after commit
7a3f5b0de364 (“netfilter: add netfilter hooks to SRv6 data plane”),
where the entire seg6_input() code was refactored to deal with netfilter
hooks.

The proposed patch addresses the identified memory leak by requiring the
seg6_input_core() function to release the sk_buff in the event that
skb_cow_head() fails.

CNA Affected

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    "product": "Linux",
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        "version": "af3b5158b89d",
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    ],
    "programFiles": [
      "net/ipv6/seg6_iptunnel.c"
    ],
    "defaultStatus": "unaffected"
  },
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
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    "versions": [
      {
        "status": "affected",
        "version": "4.12"
      },
      {
        "status": "unaffected",
        "version": "0",
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      },
      {
        "status": "unaffected",
        "version": "5.15.161",
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      {
        "status": "unaffected",
        "version": "6.1.93",
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      {
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        "version": "6.6.33",
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      {
        "status": "unaffected",
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        "versionType": "original_commit_for_fix",
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    "programFiles": [
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]