2 files changed, 32 insertions, 11 deletions
diff --git a/src/corelib/io/qiodevice_p.h b/src/corelib/io/qiodevice_p.h
index 881d85904c..c6b27b1e16 100644
--- a/src/corelib/io/qiodevice_p.h
+++ b/src/corelib/io/qiodevice_p.h
@@ -110,6 +110,11 @@ public:
         first += r;
         return r;
     }
+    int peek(char* target, int size) {
+        int r = qMin(size, len);
+        memcpy(target, first, r);
+        return r;
+    }
     char* reserve(int size) {
         makeSpace(size + len, freeSpaceAtEnd);
         char* writePtr = first + len;
diff --git a/src/network/ssl/qsslsocket.cpp b/src/network/ssl/qsslsocket.cpp
index 7fc36c8523..2b809a70d3 100644
--- a/src/network/ssl/qsslsocket.cpp
+++ b/src/network/ssl/qsslsocket.cpp
@@ -2249,15 +2249,24 @@ void QSslSocketPrivate::_q_flushReadBuffer()
 qint64 QSslSocketPrivate::peek(char *data, qint64 maxSize)
 {
     if (mode == QSslSocket::UnencryptedMode && !autoStartHandshake) {
-        if (plainSocket)
-            return plainSocket->peek(data, maxSize);
-        else
+        //unencrypted mode - do not use QIODevice::peek, as it reads ahead data from the plain socket
+        //peek at data already in the QIODevice buffer (from a previous read)
+        qint64 r = buffer.peek(data, maxSize);
+        if (r == maxSize)
+            return r;
+        data += r;
+        //peek at data in the plain socket
+        if (plainSocket) {
+            qint64 r2 = plainSocket->peek(data, maxSize - r);
+            if (r2 < 0)
+                return (r > 0 ? r : r2);
+            return r + r2;
+        } else {
             return -1;
+        }
     } else {
-        QByteArray tmp;
-        tmp = readBuffer.peek(maxSize);
-        memcpy(data, tmp.data(), tmp.length());
-        return tmp.length();
+        //encrypted mode - the socket engine will read and decrypt data into the QIODevice buffer
+        return QTcpSocketPrivate::peek(data, maxSize);
     }
 }
 
@@ -2267,14 +2276,21 @@ qint64 QSslSocketPrivate::peek(char *data, qint64 maxSize)
 QByteArray QSslSocketPrivate::peek(qint64 maxSize)
 {
     if (mode == QSslSocket::UnencryptedMode && !autoStartHandshake) {
+        //unencrypted mode - do not use QIODevice::peek, as it reads ahead data from the plain socket
+        //peek at data already in the QIODevice buffer (from a previous read)
+        QByteArray ret;
+        ret.reserve(maxSize);
+        ret.resize(buffer.peek(ret.data(), maxSize));
+        if (ret.length() == maxSize)
+            return ret;
+        //peek at data in the plain socket
         if (plainSocket)
-            return plainSocket->peek(maxSize);
+            return ret + plainSocket->peek(maxSize - ret.length());
         else
             return QByteArray();
     } else {
-        QByteArray tmp;
-        tmp = readBuffer.peek(maxSize);
-        return tmp;
+        //encrypted mode - the socket engine will read and decrypt data into the QIODevice buffer
+        return QTcpSocketPrivate::peek(maxSize);
     }
 }