CVE-2022-50731 (GCVE-0-2022-50731)

Vulnerability from cvelistv5 – Published: 2025-12-24 12:22 – Updated: 2025-12-24 12:22
VLAI?
Title
crypto: akcipher - default implementation for setting a private key
Summary
In the Linux kernel, the following vulnerability has been resolved: crypto: akcipher - default implementation for setting a private key Changes from v1: * removed the default implementation from set_pub_key: it is assumed that an implementation must always have this callback defined as there are no use case for an algorithm, which doesn't need a public key Many akcipher implementations (like ECDSA) support only signature verifications, so they don't have all callbacks defined. Commit 78a0324f4a53 ("crypto: akcipher - default implementations for request callbacks") introduced default callbacks for sign/verify operations, which just return an error code. However, these are not enough, because before calling sign the caller would likely call set_priv_key first on the instantiated transform (as the in-kernel testmgr does). This function does not have a default stub, so the kernel crashes, when trying to set a private key on an akcipher, which doesn't support signature generation. I've noticed this, when trying to add a KAT vector for ECDSA signature to the testmgr. With this patch the testmgr returns an error in dmesg (as it should) instead of crashing the kernel NULL ptr dereference.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 78a0324f4a5328088fea9426cfe1d1851276c475 , < 95c4e20adc3ea00d1594a2a05d9b187ed12ffa8e (git)
Affected: 78a0324f4a5328088fea9426cfe1d1851276c475 , < a1354bdd191d533211b7cb723aa76a66f516f197 (git)
Affected: 78a0324f4a5328088fea9426cfe1d1851276c475 , < 779a9930f3e152c82699feb389a0e6d6644e747e (git)
Affected: 78a0324f4a5328088fea9426cfe1d1851276c475 , < 85bc736a18b872f54912e8bb70682d11770aece0 (git)
Affected: 78a0324f4a5328088fea9426cfe1d1851276c475 , < f9058178597059d6307efe96a7916600f8ede08c (git)
Affected: 78a0324f4a5328088fea9426cfe1d1851276c475 , < bc155c6c188c2f0c5749993b1405673d25a80389 (git)
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    Linux Linux Affected: 5.2
Unaffected: 0 , < 5.2 (semver)
Unaffected: 5.4.220 , ≤ 5.4.* (semver)
Unaffected: 5.10.150 , ≤ 5.10.* (semver)
Unaffected: 5.15.75 , ≤ 5.15.* (semver)
Unaffected: 5.19.17 , ≤ 5.19.* (semver)
Unaffected: 6.0.3 , ≤ 6.0.* (semver)
Unaffected: 6.1 , ≤ * (original_commit_for_fix)
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