CVE-2024-26831 net/handshake: Fix handshake_req_destroy_test1

2024-04-1709:43:54

Linux

www.cve.org

vulnerability

linux kernel

memory leak

handshake_req_destroy_test1

sock_release

fput

api bug

6.7 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

15.5%

JSON

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

net/handshake: Fix handshake_req_destroy_test1

Recently, handshake_req_destroy_test1 started failing:

Expected handshake_req_destroy_test == req, but
handshake_req_destroy_test == 0000000000000000
req == 0000000060f99b40
not ok 11 req_destroy works

This is because “sock_release(sock)” was replaced with “fput(filp)”
to address a memory leak. Note that sock_release() is synchronous
but fput() usually delays the final close and clean-up.

The delay is not consequential in the other cases that were changed
but handshake_req_destroy_test1 is testing that handshake_req_cancel()
followed by closing the file actually does call the ->hp_destroy
method. Thus the PTR_EQ test at the end has to be sure that the
final close is complete before it checks the pointer.

We cannot use a completion here because if ->hp_destroy is never
called (ie, there is an API bug) then the test will hang.

Reported by: Guenter Roeck <[email protected]>

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "net/handshake/handshake-test.c"
    ],
    "versions": [
      {
        "version": "4a0f07d71b04",
        "lessThan": "d74226e03df1",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "4a0f07d71b04",
        "lessThan": "7f97805b8df6",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "4a0f07d71b04",
        "lessThan": "4e1d71cabb19",
        "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/handshake/handshake-test.c"
    ],
    "versions": [
      {
        "version": "6.6",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "6.6",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6.18",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.7.6",
        "lessThanOrEqual": "6.7.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.8",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]