Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security

Pull key handling fixes from James Morris:
 "Quoting David Howells:

  Here are three miscellaneous fixes:

  (1) Fix a panic in some debugging code in PKCS#7.  This can only
      happen by explicitly inserting a #define DEBUG into the code.

  (2) Fix the calculation of the digest length in the PE file parser.
      This causes a failure where there should be a success.

  (3) Fix the case where an X.509 cert can be added as an asymmetric key
      to a trusted keyring with no trust restriction if no AKID is
      supplied.

  Bugs (1) and (2) aren't particularly problematic, but (3) allows a
  security check to be bypassed.  Happily, this is a recent regression
  and never made it into a released kernel"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  KEYS: Fix for erroneous trust of incorrectly signed X.509 certs
  pefile: Fix the failure of calculation for digest
  PKCS#7: Fix panic when referring to the empty AKID when DEBUG defined

3 files changed, 8 insertions, 3 deletions

diff --git a/crypto/asymmetric_keys/mscode_parser.c b/crypto/asymmetric_keys/mscode_parser.c
index 6a76d5c70ef6..9492e1c22d38 100644
--- a/crypto/asymmetric_keys/mscode_parser.c
+++ b/crypto/asymmetric_keys/mscode_parser.c
@@ -124,5 +124,10 @@ int mscode_note_digest(void *context, size_t hdrlen,
 	struct pefile_context *ctx = context;
 
 	ctx->digest = kmemdup(value, vlen, GFP_KERNEL);
-	return ctx->digest ? 0 : -ENOMEM;
+	if (!ctx->digest)
+		return -ENOMEM;
+
+	ctx->digest_len = vlen;
+
+	return 0;
 }
diff --git a/crypto/asymmetric_keys/pkcs7_verify.c b/crypto/asymmetric_keys/pkcs7_verify.c
index 44b746e9df1b..2ffd69769466 100644
--- a/crypto/asymmetric_keys/pkcs7_verify.c
+++ b/crypto/asymmetric_keys/pkcs7_verify.c
@@ -227,7 +227,7 @@ static int pkcs7_verify_sig_chain(struct pkcs7_message *pkcs7,
 				if (asymmetric_key_id_same(p->id, auth))
 					goto found_issuer_check_skid;
 			}
-		} else {
+		} else if (sig->auth_ids[1]) {
 			auth = sig->auth_ids[1];
 			pr_debug("- want %*phN\n", auth->len, auth->data);
 			for (p = pkcs7->certs; p; p = p->next) {
diff --git a/crypto/asymmetric_keys/restrict.c b/crypto/asymmetric_keys/restrict.c
index ac4bddf669de..19d1afb9890f 100644
--- a/crypto/asymmetric_keys/restrict.c
+++ b/crypto/asymmetric_keys/restrict.c
@@ -87,7 +87,7 @@ int restrict_link_by_signature(struct key *trust_keyring,
 
 	sig = payload->data[asym_auth];
 	if (!sig->auth_ids[0] && !sig->auth_ids[1])
-		return 0;
+		return -ENOKEY;
 
 	if (ca_keyid && !asymmetric_key_id_partial(sig->auth_ids[1], ca_keyid))
 		return -EPERM;