Add more |bpc| value check in GetValidBpc()

core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp

Index: core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp
diff --git a/core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp b/core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp
index 7e80f75269dfe4af41f9f5dae0275ea4fef434ec..6b484cca565b71b27fdef43b5985dd0583e96284 100644
--- a/core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp
+++ b/core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp
@@ -919,15 +919,23 @@ FX_DWORD CPDF_DIBSource::GetValidBpc() const
             }
         }
     }
+    if (bpc != 1 && bpc != 2 && bpc != 4 && bpc != 8 && bpc != 12 && bpc != 16) {
+        bpc = 0;
+    }
+
     return bpc;
 }
 #define NORMALCOLOR_MAX(color, max) (color) > (max) ? (max) : (color) < 0 ? 0 : (color);
 void CPDF_DIBSource::TranslateScanline24bpp(FX_LPBYTE dest_scan, FX_LPCBYTE src_scan) const
 {
-    int max_data = (1 << m_bpc) - 1;
+    FX_DWORD bpc = GetValidBpc();
+    if (bpc == 0) {
+        return;
+    }
+    int max_data = (1 << bpc) - 1;
     if (m_bDefaultDecode) {
         if (m_Family == PDFCS_DEVICERGB || m_Family == PDFCS_CALRGB) {
-            if (m_bpc == 16) {
+            if (bpc == 16) {

[Tom Sepez, 2014/08/01 20:33:53]

nit: someday down the road, this might be better served by a switch statement.

[Bo Xu, 2014/08/01 21:03:01]

Changed to switch statement.

                 FX_LPCBYTE src_pos = src_scan;
                 for (int col = 0; col < m_Width; col ++) {
                     *dest_scan++ = src_pos[4];
@@ -935,7 +943,8 @@ void CPDF_DIBSource::TranslateScanline24bpp(FX_LPBYTE dest_scan, FX_LPCBYTE src_
                     *dest_scan++ = *src_pos;
                     src_pos += 6;
                 }
-            } else if (m_bpc == 8) {
+            }

[Tom Sepez, 2014/08/01 20:33:53]

nit: this indentation style doesn't match what's in-use throughout the rest of
the file. Although it may be clearer the way you've written it, I'd encourage
you do it consistently with the existing convention for consistency.

[Bo Xu, 2014/08/01 21:03:01]

Done.

+            else if (bpc == 8) {
                 FX_LPCBYTE src_pos = src_scan;
                 for (int column = 0; column < m_Width; column ++) {
                     *dest_scan++ = src_pos[2];
@@ -943,10 +952,10 @@ void CPDF_DIBSource::TranslateScanline24bpp(FX_LPBYTE dest_scan, FX_LPCBYTE src_
                     *dest_scan++ = *src_pos;
                     src_pos += 3;
                 }
-            } else {
+            }
+            else {
                 int src_bit_pos = 0;
                 int dest_byte_pos = 0;
-                FX_DWORD bpc = GetValidBpc();
                 for (int column = 0; column < m_Width; column ++) {
                     int R = _GetBits8(src_scan, src_bit_pos, bpc);
                     src_bit_pos += bpc;
@@ -964,7 +973,8 @@ void CPDF_DIBSource::TranslateScanline24bpp(FX_LPBYTE dest_scan, FX_LPCBYTE src_
                 }
             }
             return;
-        } else if (m_bpc == 8) {
+        }
+        else if (bpc == 8) {
             if (m_nComponents == m_pColorSpace->CountComponents())
                 m_pColorSpace->TranslateImageLine(dest_scan, src_scan, m_Width, m_Width, m_Height,
                                                   m_bLoadMask && m_GroupFamily == PDFCS_DEVICECMYK && m_Family == PDFCS_DEVICECMYK);
@@ -974,7 +984,7 @@ void CPDF_DIBSource::TranslateScanline24bpp(FX_LPBYTE dest_scan, FX_LPCBYTE src_
     CFX_FixedBufGrow<FX_FLOAT, 16> color_values1(m_nComponents);
     FX_FLOAT* color_values = color_values1;
     FX_FLOAT R = 0.0f, G = 0.0f, B = 0.0f;
-    if (m_bpc == 8) {
+    if (bpc == 8) {
         int src_byte_pos = 0;
         int dest_byte_pos = 0;
         for (int column = 0; column < m_Width; column ++) {