CVE-2024-26665 tunnels: fix out of bounds access when building IPv6 PMTU error

2024-04-0206:22:14

Linux

www.cve.org

linux kernel

ipv6

pmtuerror

outofboundsaccess

vulnerability

7.6 High

AI Score

Confidence

High

0.0004 Low

EPSS

Percentile

10.4%

JSON

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

tunnels: fix out of bounds access when building IPv6 PMTU error

If the ICMPv6 error is built from a non-linear skb we get the following
splat,

BUG: KASAN: slab-out-of-bounds in do_csum+0x220/0x240
Read of size 4 at addr ffff88811d402c80 by task netperf/820
CPU: 0 PID: 820 Comm: netperf Not tainted 6.8.0-rc1+ #543
…
kasan_report+0xd8/0x110
do_csum+0x220/0x240
csum_partial+0xc/0x20
skb_tunnel_check_pmtu+0xeb9/0x3280
vxlan_xmit_one+0x14c2/0x4080
vxlan_xmit+0xf61/0x5c00
dev_hard_start_xmit+0xfb/0x510
__dev_queue_xmit+0x7cd/0x32a0
br_dev_queue_push_xmit+0x39d/0x6a0

Use skb_checksum instead of csum_partial who cannot deal with non-linear
SKBs.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "net/ipv4/ip_tunnel_core.c"
    ],
    "versions": [
      {
        "version": "4cb47a8644cc",
        "lessThan": "e77bf828f1ca",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "4cb47a8644cc",
        "lessThan": "d964dd1bc145",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "4cb47a8644cc",
        "lessThan": "e37cde7a5716",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "4cb47a8644cc",
        "lessThan": "510c869ffa40",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "4cb47a8644cc",
        "lessThan": "7dc9feb8b170",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "4cb47a8644cc",
        "lessThan": "d75abeec401f",
        "status": "affected",
        "versionType": "git"
      }
    ]
  },
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "affected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "net/ipv4/ip_tunnel_core.c"
    ],
    "versions": [
      {
        "version": "5.9",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "5.9",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.10.210",
        "lessThanOrEqual": "5.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "5.15.149",
        "lessThanOrEqual": "5.15.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.1.78",
        "lessThanOrEqual": "6.1.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6.17",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.7.5",
        "lessThanOrEqual": "6.7.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.8",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]