diff options
Diffstat (limited to 'src/network/kernel/qdnslookup_unix.cpp')
-rw-r--r-- | src/network/kernel/qdnslookup_unix.cpp | 27 |
1 files changed, 22 insertions, 5 deletions
diff --git a/src/network/kernel/qdnslookup_unix.cpp b/src/network/kernel/qdnslookup_unix.cpp index 1da00813ce..ce1ec6442a 100644 --- a/src/network/kernel/qdnslookup_unix.cpp +++ b/src/network/kernel/qdnslookup_unix.cpp @@ -42,6 +42,7 @@ #if QT_CONFIG(library) #include <qlibrary.h> #endif +#include <qvarlengtharray.h> #include <qscopedpointer.h> #include <qurl.h> #include <private/qnativesocketengine_p.h> @@ -58,6 +59,8 @@ # include <gnu/lib-names.h> #endif +#include <cstring> + QT_BEGIN_NAMESPACE #if QT_CONFIG(library) @@ -137,7 +140,7 @@ void QDnsLookupRunnable::query(const int requestType, const QByteArray &requestN // Initialize state. struct __res_state state; - memset(&state, 0, sizeof(state)); + std::memset(&state, 0, sizeof(state)); if (local_res_ninit(&state) < 0) { reply->error = QDnsLookup::ResolverError; reply->errorString = tr("Resolver initialization failed"); @@ -189,11 +192,25 @@ void QDnsLookupRunnable::query(const int requestType, const QByteArray &requestN QScopedPointer<struct __res_state, QDnsLookupStateDeleter> state_ptr(&state); // Perform DNS query. - unsigned char response[PACKETSZ]; - memset(response, 0, sizeof(response)); - const int responseLength = local_res_nquery(&state, requestName, C_IN, requestType, response, sizeof(response)); + QVarLengthArray<unsigned char, PACKETSZ> buffer(PACKETSZ); + std::memset(buffer.data(), 0, buffer.size()); + int responseLength = local_res_nquery(&state, requestName, C_IN, requestType, buffer.data(), buffer.size()); + if (Q_UNLIKELY(responseLength > PACKETSZ)) { + buffer.resize(responseLength); + std::memset(buffer.data(), 0, buffer.size()); + responseLength = local_res_nquery(&state, requestName, C_IN, requestType, buffer.data(), buffer.size()); + if (Q_UNLIKELY(responseLength > buffer.size())) { + // Ok, we give up. + reply->error = QDnsLookup::ResolverError; + reply->errorString.clear(); // We cannot be more specific, alas. + return; + } + } - // Check the response header. + unsigned char *response = buffer.data(); + // Check the response header. Though res_nquery returns -1 as a + // responseLength in case of error, we still can extract the + // exact error code from the response. HEADER *header = (HEADER*)response; const int answerCount = ntohs(header->ancount); switch (header->rcode) { |