CVE-2024-45010 mptcp: pm: only mark 'subflow' endp as available

2024-09-1115:13:48

Linux

www.cve.org

mptcp

subflow

endpoint

vulnerability

linux kernel

warning

bug

removal

signal

counter

EPSS

Percentile

5.1%

JSON

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

mptcp: pm: only mark ‘subflow’ endp as available

Adding the following warning …

WARN_ON_ONCE(msk->pm.local_addr_used == 0)

… before decrementing the local_addr_used counter helped to find a bug
when running the “remove single address” subtest from the mptcp_join.sh
selftests.

Removing a ‘signal’ endpoint will trigger the removal of all subflows
linked to this endpoint via mptcp_pm_nl_rm_addr_or_subflow() with
rm_type == MPTCP_MIB_RMSUBFLOW. This will decrement the local_addr_used
counter, which is wrong in this case because this counter is linked to
‘subflow’ endpoints, and here it is a ‘signal’ endpoint that is being
removed.

Now, the counter is decremented, only if the ID is being used outside
of mptcp_pm_nl_rm_addr_or_subflow(), only for ‘subflow’ endpoints, and
if the ID is not 0 – local_addr_used is not taking into account these
ones. This marking of the ID as being available, and the decrement is
done no matter if a subflow using this ID is currently available,
because the subflow could have been closed before.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "net/mptcp/pm_netlink.c"
    ],
    "versions": [
      {
        "version": "06faa2271034",
        "lessThan": "7fdc870d0896",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "06faa2271034",
        "lessThan": "43cf912b0b0f",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "06faa2271034",
        "lessThan": "9849cfc67383",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "06faa2271034",
        "lessThan": "322ea3778965",
        "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/mptcp/pm_netlink.c"
    ],
    "versions": [
      {
        "version": "5.13",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "5.13",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.1.108",
        "lessThanOrEqual": "6.1.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6.48",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.10.7",
        "lessThanOrEqual": "6.10.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.11",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]