CVE-2024-35882 SUNRPC: Fix a slow server-side memory leak with RPC-over-TCP

2024-05-1908:34:39

Linux

www.cve.org

sunrpc

memory leak

rpc-over-tcp

linux kernel

6.3 Medium

AI Score

Confidence

Low

0.0004 Low

EPSS

Percentile

15.7%

JSON

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

SUNRPC: Fix a slow server-side memory leak with RPC-over-TCP

Jan Schunk reports that his small NFS servers suffer from memory
exhaustion after just a few days. A bisect shows that commit
e18e157bb5c8 (“SUNRPC: Send RPC message on TCP with a single
sock_sendmsg() call”) is the first bad commit.

That commit assumed that sock_sendmsg() releases all the pages in
the underlying bio_vec array, but the reality is that it doesn’t.
svc_xprt_release() releases the rqst’s response pages, but the
record marker page fragment isn’t one of those, so it is never
released.

This is a narrow fix that can be applied to stable kernels. A
more extensive fix is in the works.

CNA Affected

[
  {
    "product": "Linux",
    "vendor": "Linux",
    "defaultStatus": "unaffected",
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "programFiles": [
      "net/sunrpc/svcsock.c"
    ],
    "versions": [
      {
        "version": "e18e157bb5c8",
        "lessThan": "1ba1291172f9",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "e18e157bb5c8",
        "lessThan": "a2ebedf7bcd1",
        "status": "affected",
        "versionType": "git"
      },
      {
        "version": "e18e157bb5c8",
        "lessThan": "05258a0a69b3",
        "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/sunrpc/svcsock.c"
    ],
    "versions": [
      {
        "version": "6.6",
        "status": "affected"
      },
      {
        "version": "0",
        "lessThan": "6.6",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.6.26",
        "lessThanOrEqual": "6.6.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.8.5",
        "lessThanOrEqual": "6.8.*",
        "status": "unaffected",
        "versionType": "custom"
      },
      {
        "version": "6.9",
        "lessThanOrEqual": "*",
        "status": "unaffected",
        "versionType": "original_commit_for_fix"
      }
    ]
  }
]