Merge tag 'keys-next-20260206' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull keys update from David Howells:
 "This adds support for ML-DSA signatures in X.509 certificates and
  PKCS#7/CMS messages, thereby allowing this algorithm to be used for
  signing modules, kexec'able binaries, wifi regulatory data, etc..

  This requires OpenSSL-3.5 at a minimum and preferably OpenSSL-4 (so
  that it can avoid the use of CMS signedAttrs - but that version is not
  cut yet). certs/Kconfig does a check to hide the signing options if
  OpenSSL does not list the algorithm as being available"

* tag 'keys-next-20260206' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  pkcs7: Change a pr_warn() to pr_warn_once()
  pkcs7: Allow authenticatedAttributes for ML-DSA
  modsign: Enable ML-DSA module signing
  pkcs7, x509: Add ML-DSA support
  pkcs7: Allow the signing algo to do whatever digestion it wants itself
  pkcs7, x509: Rename ->digest to ->m
  x509: Separately calculate sha256 for blacklist
  crypto: Add ML-DSA crypto_sig support

1 files changed, 9 insertions, 7 deletions

diff --git a/Documentation/admin-guide/module-signing.rst b/Documentation/admin-guide/module-signing.rst
index a8667a777490..7f2f127dc76f 100644
--- a/Documentation/admin-guide/module-signing.rst
+++ b/Documentation/admin-guide/module-signing.rst
@@ -28,10 +28,12 @@ trusted userspace bits.
 
 This facility uses X.509 ITU-T standard certificates to encode the public keys
 involved.  The signatures are not themselves encoded in any industrial standard
-type.  The built-in facility currently only supports the RSA & NIST P-384 ECDSA
-public key signing standard (though it is pluggable and permits others to be
-used).  The possible hash algorithms that can be used are SHA-2 and SHA-3 of
-sizes 256, 384, and 512 (the algorithm is selected by data in the signature).
+type.  The built-in facility currently only supports the RSA, NIST P-384 ECDSA
+and NIST FIPS-204 ML-DSA public key signing standards (though it is pluggable
+and permits others to be used).  For RSA and ECDSA, the possible hash
+algorithms that can be used are SHA-2 and SHA-3 of sizes 256, 384, and 512 (the
+algorithm is selected by data in the signature); ML-DSA does its own hashing,
+but is allowed to be used with a SHA512 hash for signed attributes.
 
 
 ==========================
@@ -146,9 +148,9 @@ into vmlinux) using parameters in the::
 
 file (which is also generated if it does not already exist).
 
-One can select between RSA (``MODULE_SIG_KEY_TYPE_RSA``) and ECDSA
-(``MODULE_SIG_KEY_TYPE_ECDSA``) to generate either RSA 4k or NIST
-P-384 keypair.
+One can select between RSA (``MODULE_SIG_KEY_TYPE_RSA``), ECDSA
+(``MODULE_SIG_KEY_TYPE_ECDSA``) and ML-DSA (``MODULE_SIG_KEY_TYPE_MLDSA_*``) to
+generate an RSA 4k, a NIST P-384 keypair or an ML-DSA 44, 65 or 87 keypair.
 
 It is strongly recommended that you provide your own x509.genkey file.