SMIME_text(): add missing I/O error checking

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/27368)

diff --git a/crypto/asn1/asn_mime.c b/crypto/asn1/asn_mime.c
index fc0a73c56646333d1e3f06d645142341369b5473..8c99b6ba3dc019a0366933957691b818ccad8a3a 100644 (file)
--- a/crypto/asn1/asn_mime.c
+++ b/crypto/asn1/asn_mime.c
@@ -633,10 +633,9 @@ int SMIME_text(BIO *in, BIO *out)
     }
     sk_MIME_HEADER_pop_free(headers, mime_hdr_free);
     while ((len = BIO_read(in, iobuf, sizeof(iobuf))) > 0)
-        BIO_write(out, iobuf, len);
-    if (len < 0)
-        return 0;
-    return 1;
+        if (BIO_write(out, iobuf, len) != len && out != NULL)
+            return 0;
+    return len >= 0;
 }
 
 /*