CVE-2024-26800 tls: fix use-after-free on failed backlog decryption

2024-04-0408:20:28

Linux

github.com

cve-2024-26800

linux kernel

tls

use-after-free

decryption

vulnerability

AI Score

Confidence

Low

SSVC

Exploitation

none

Automatable

Technical Impact

partial

JSON

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

tls: fix use-after-free on failed backlog decryption

When the decrypt request goes to the backlog and crypto_aead_decrypt
returns -EBUSY, tls_do_decryption will wait until all async
decryptions have completed. If one of them fails, tls_do_decryption
will return -EBADMSG and tls_decrypt_sg jumps to the error path,
releasing all the pages. But the pages have been passed to the async
callback, and have already been released by tls_decrypt_done.

The only true async case is when crypto_aead_decrypt returns
-EINPROGRESS. With -EBUSY, we already waited so we can tell
tls_sw_recvmsg that the data is available for immediate copy, but we
need to notify tls_decrypt_sg (via the new ->async_done flag) that the
memory has already been released.

CNA Affected

[
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "cd1bbca03f3c",
        "lessThan": "f2b85a4cc763",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "13eca403876b",
        "lessThan": "81be85353b0f",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "ab6397f072e5",
        "lessThan": "1ac9fb84bc7e",
        "versionType": "git"
      },
      {
        "status": "affected",
        "version": "859054147318",
        "lessThan": "13114dc55430",
        "versionType": "git"
      }
    ],
    "programFiles": [
      "net/tls/tls_sw.c"
    ],
    "defaultStatus": "unaffected"
  },
  {
    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
    "vendor": "Linux",
    "product": "Linux",
    "versions": [
      {
        "status": "affected",
        "version": "6.6.18",
        "lessThan": "6.6.21",
        "versionType": "custom"
      },
      {
        "status": "affected",
        "version": "6.7.6",
        "lessThan": "6.7.9",
        "versionType": "custom"
      }
    ],
    "programFiles": [
      "net/tls/tls_sw.c"
    ],
    "defaultStatus": "unaffected"
  }
]