diff --git a/crypto/openssl/doc/man3/SSL_write.pod b/crypto/openssl/doc/man3/SSL_write.pod
--- a/crypto/openssl/doc/man3/SSL_write.pod
+++ b/crypto/openssl/doc/man3/SSL_write.pod
@@ -120,7 +120,8 @@
 =item Z<>>= 0
 
 The write operation was successful, the return value is the number
-of bytes of the file written to the TLS/SSL connection.
+of bytes of the file written to the TLS/SSL connection. The return
+value can be less than B<size> for a partial write.
 
 =item E<lt> 0
 
diff --git a/crypto/openssl/include/internal/ktls.h b/crypto/openssl/include/internal/ktls.h
--- a/crypto/openssl/include/internal/ktls.h
+++ b/crypto/openssl/include/internal/ktls.h
@@ -192,15 +192,12 @@
 static ossl_inline ossl_ssize_t ktls_sendfile(int s, int fd, off_t off,
                                               size_t size, int flags)
 {
-    off_t sbytes;
+    off_t sbytes = 0;
     int ret;
 
     ret = sendfile(fd, s, off, size, NULL, &sbytes, flags);
-    if (ret == -1) {
-	    if (errno == EAGAIN && sbytes != 0)
-		    return sbytes;
-	    return -1;
-    }
+    if (ret == -1 && sbytes == 0)
+        return -1;
     return sbytes;
 }