gentoo-overlay/dev-qt/qtcore/files/qtcore-5.15.2-fix-UB-in-QDateTime.patch

From d2c0fc2b5f1c07c1e0acb1c0127578066b6f9b8e Mon Sep 17 00:00:00 2001
From: Edward Welbourne <edward.welbourne@qt.io>
Date: Tue, 24 Nov 2020 12:45:11 +0100
Subject: [PATCH] Bounds-check time-zone offsets when parsing

Parsing of time-zone offsets should check the offset string conforms
to the expected format and has valid values in its fields. The
QDateTime parser, fromOffsetString(), neglected the bounds check on
hours; the QTzTimeZonePrivate parser, parsePosixTime(), neglected all
upper bounds checks, only checking against negative valus.

Drive-by - refined phrasing of a comment.

Fixes: QTBUG-88656
Change-Id: If04cdbe65064108eaa87c42310527783ad21b4c0
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
(cherry picked from commit 380d97e1bd15e753907c378a070bdf7f1c1cf06e)
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
---
 src/corelib/time/qdatetime.cpp           |  2 +-
 src/corelib/time/qtimezoneprivate_tz.cpp | 27 ++++++++++++++++-----------
 2 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/src/corelib/time/qdatetime.cpp b/src/corelib/time/qdatetime.cpp
index e824787880c..a2816e87f4a 100644
--- a/src/corelib/time/qdatetime.cpp
+++ b/src/corelib/time/qdatetime.cpp
@@ -240,7 +240,7 @@ static int fromOffsetString(QStringView offsetString, bool *valid) noexcept
     const QStringView hhRef = time.left(qMin(hhLen, time.size()));
     bool ok = false;
     const int hour = C.toInt(hhRef, &ok);
-    if (!ok)
+    if (!ok || hour > 23) // More generous than QTimeZone::MaxUtcOffsetSecs
         return 0;
 
     const QStringView mmRef = time.mid(qMin(mmIndex, time.size()));
diff --git a/src/corelib/time/qtimezoneprivate_tz.cpp b/src/corelib/time/qtimezoneprivate_tz.cpp
index b816b4ecff2..adc590878d7 100644
--- a/src/corelib/time/qtimezoneprivate_tz.cpp
+++ b/src/corelib/time/qtimezoneprivate_tz.cpp
@@ -394,29 +394,34 @@ static int parsePosixTime(const char *begin, const char *end)
     // Format "hh[:mm[:ss]]"
     int hour, min = 0, sec = 0;
 
-    // Note that the calls to qstrtoll do *not* check the end pointer, which
-    // means they proceed until they find a non-digit. We check that we're
-    // still in range at the end, but we may have read from past end. It's the
-    // caller's responsibility to ensure that begin is part of a
-    // null-terminated string.
+    // Note that the calls to qstrtoll do *not* check against the end pointer,
+    // which means they proceed until they find a non-digit. We check that we're
+    // still in range at the end, but we may have read past end. It's the
+    // caller's responsibility to ensure that begin is part of a null-terminated
+    // string.
 
+    const int maxHour = QTimeZone::MaxUtcOffsetSecs / 3600;
     bool ok = false;
-    hour = qstrtoll(begin, &begin, 10, &ok);
-    if (!ok || hour < 0)
+    const char *cut = begin;
+    hour = qstrtoll(begin, &cut, 10, &ok);
+    if (!ok || hour < 0 || hour > maxHour || cut > begin + 2)
         return INT_MIN;
+    begin = cut;
     if (begin < end && *begin == ':') {
         // minutes
         ++begin;
-        min = qstrtoll(begin, &begin, 10, &ok);
-        if (!ok || min < 0)
+        min = qstrtoll(begin, &cut, 10, &ok);
+        if (!ok || min < 0 || min > 59 || cut > begin + 2)
             return INT_MIN;
 
+        begin = cut;
         if (begin < end && *begin == ':') {
             // seconds
             ++begin;
-            sec = qstrtoll(begin, &begin, 10, &ok);
-            if (!ok || sec < 0)
+            sec = qstrtoll(begin, &cut, 10, &ok);
+            if (!ok || sec < 0 || sec > 59 || cut > begin + 2)
                 return INT_MIN;
+            begin = cut;
         }
     }
 
-- 
2.16.3