Fix error check in pgp_enumerate_blob

ya-isakov · Dec 4, 2021 · d4b5890 · d4b5890
1 parent 21347de
commit d4b5890
Showing 1 changed file with 6 additions and 4 deletions.
diff --git a/src/libopensc/card-openpgp.c b/src/libopensc/card-openpgp.c
@@ -1246,14 +1246,16 @@ pgp_enumerate_blob(sc_card_t *card, pgp_blob_t *blob)
 
 		r = sc_asn1_read_tag(&data, blob->len - (in - blob->data),
 					&cla, &tag, &len);
-		if (data == NULL) {
-			sc_log(card->ctx, "Unexpected end of contents");
-			return SC_ERROR_OBJECT_NOT_VALID;
-		}
 		if (r == SC_ERROR_INVALID_ASN1_OBJECT) {
 			sc_log(card->ctx, "Invalid ASN.1 object");
 			return SC_ERROR_OBJECT_NOT_VALID;
 		}
+		/* Check for unknown error, or empty data */
+		if (((r < 0) && (r != SC_ERROR_ASN1_END_OF_CONTENTS)) ||
+		    (data == NULL)) {
+			sc_log(card->ctx, "Unexpected end of contents");
+			return SC_ERROR_OBJECT_NOT_VALID;
+		}
 
 		/* undo ASN1's split of tag & class */
 		for (tmptag = tag; tmptag > 0x0FF; tmptag >>= 8) {