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

Pull key subsystem fixes from James Morris:
 "Fixes for the keys subsystem, one of which addresses a use-after-free
  bug"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  PEFILE: Relax the check on the length of the PKCS#7 cert
  KEYS: Fix use-after-free in assoc_array_gc()
  KEYS: Fix public_key asymmetric key subtype name
  KEYS: Increase root_maxkeys and root_maxbytes sizes

crypto/asymmetric_keys/public_key.c

@@ -121,6 +121,7 @@ static int public_key_verify_signature_2(const struct key *key,
 struct asymmetric_key_subtype public_key_subtype = {
 	.owner			= THIS_MODULE,
 	.name			= "public_key",
+	.name_len		= sizeof("public_key") - 1,
 	.describe		= public_key_describe,
 	.destroy		= public_key_destroy,
 	.verify_signature	= public_key_verify_signature_2,

crypto/asymmetric_keys/verify_pefile.c

@@ -128,6 +128,7 @@ static int pefile_strip_sig_wrapper(const void *pebuf,
 {
 	struct win_certificate wrapper;
 	const u8 *pkcs7;
+	unsigned len;
 
 	if (ctx->sig_len < sizeof(wrapper)) {
 		pr_debug("Signature wrapper too short\n");
@@ -154,33 +155,49 @@ static int pefile_strip_sig_wrapper(const void *pebuf,
 		return -ENOTSUPP;
 	}
 
-	/* Looks like actual pkcs signature length is in wrapper->length.
-	 * size obtained from data dir entries lists the total size of
-	 * certificate table which is also aligned to octawrod boundary.
-	 *
-	 * So set signature length field appropriately.
+	/* It looks like the pkcs signature length in wrapper->length and the
+	 * size obtained from the data dir entries, which lists the total size
+	 * of certificate table, are both aligned to an octaword boundary, so
+	 * we may have to deal with some padding.
 	 */
 	ctx->sig_len = wrapper.length;
 	ctx->sig_offset += sizeof(wrapper);
 	ctx->sig_len -= sizeof(wrapper);
-	if (ctx->sig_len == 0) {
+	if (ctx->sig_len < 4) {
 		pr_debug("Signature data missing\n");
 		return -EKEYREJECTED;
 	}
 
-	/* What's left should a PKCS#7 cert */
+	/* What's left should be a PKCS#7 cert */
 	pkcs7 = pebuf + ctx->sig_offset;
-	if (pkcs7[0] == (ASN1_CONS_BIT | ASN1_SEQ)) {
-		if (pkcs7[1] == 0x82 &&
-		    pkcs7[2] == (((ctx->sig_len - 4) >> 8) & 0xff) &&
-		    pkcs7[3] ==  ((ctx->sig_len - 4)       & 0xff))
-			return 0;
-		if (pkcs7[1] == 0x80)
-			return 0;
-		if (pkcs7[1] > 0x82)
-			return -EMSGSIZE;
+	if (pkcs7[0] != (ASN1_CONS_BIT | ASN1_SEQ))
+		goto not_pkcs7;
+
+	switch (pkcs7[1]) {
+	case 0 ... 0x7f:
+		len = pkcs7[1] + 2;
+		goto check_len;
+	case ASN1_INDEFINITE_LENGTH:
+		return 0;
+	case 0x81:
+		len = pkcs7[2] + 3;
+		goto check_len;
+	case 0x82:
+		len = ((pkcs7[2] << 8) | pkcs7[3]) + 4;
+		goto check_len;
+	case 0x83 ... 0xff:
+		return -EMSGSIZE;
+	default:
+		goto not_pkcs7;
 	}
 
+check_len:
+	if (len <= ctx->sig_len) {
+		/* There may be padding */
+		ctx->sig_len = len;
+		return 0;
+	}
+not_pkcs7:
 	pr_debug("Signature data not PKCS#7\n");
 	return -ELIBBAD;
 }

lib/assoc_array.c

@@ -1735,7 +1735,7 @@ int assoc_array_gc(struct assoc_array *array,
 gc_complete:
 	edit->set[0].to = new_root;
 	assoc_array_apply_edit(edit);
-	edit->array->nr_leaves_on_tree = nr_leaves_on_tree;
+	array->nr_leaves_on_tree = nr_leaves_on_tree;
 	return 0;
 
 enomem:

security/keys/key.c

@@ -27,8 +27,8 @@ DEFINE_SPINLOCK(key_serial_lock);
 struct rb_root	key_user_tree; /* tree of quota records indexed by UID */
 DEFINE_SPINLOCK(key_user_lock);
 
-unsigned int key_quota_root_maxkeys = 200;	/* root's key count quota */
-unsigned int key_quota_root_maxbytes = 20000;	/* root's key space quota */
+unsigned int key_quota_root_maxkeys = 1000000;	/* root's key count quota */
+unsigned int key_quota_root_maxbytes = 25000000; /* root's key space quota */
 unsigned int key_quota_maxkeys = 200;		/* general key count quota */
 unsigned int key_quota_maxbytes = 20000;	/* general key space quota */