[gthumb] jpeg loader: crash when the original size is too big for a cairo surface

[Paolo Bacchilega <paobac src gnome org>]

commit 5bc151d4cf1b42cb42a846d946bd51ae32a510e0
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Mon Dec 16 12:01:07 2019 +0100

    jpeg loader: crash when the original size is too big for a cairo surface
    
    Iterate over the cairo surface dimensions instead of the
    original dimensions when copying the pixels into the cairo
    surface.

 extensions/cairo_io/cairo-image-surface-jpeg.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)
---
diff --git a/extensions/cairo_io/cairo-image-surface-jpeg.c b/extensions/cairo_io/cairo-image-surface-jpeg.c
index 3453d5a1..e0e7379e 100644
--- a/extensions/cairo_io/cairo-image-surface-jpeg.c
+++ b/extensions/cairo_io/cairo-image-surface-jpeg.c
@@ -304,7 +304,7 @@ _cairo_image_surface_create_from_jpeg (GInputStream  *istream,
                        CMYK_table_init ();
                        cmyk_tab = CMYK_Tab;
 
-                       while (srcinfo.output_scanline < srcinfo.output_height) {
+                       while (srcinfo.output_scanline < destination_height) {
                                if (g_cancellable_is_cancelled (cancellable))
                                        goto stop_loading;
 
@@ -318,7 +318,7 @@ _cairo_image_surface_create_from_jpeg (GInputStream  *istream,
                                        if (g_cancellable_is_cancelled (cancellable))
                                                goto stop_loading;
 
-                                       for (x = 0; x < srcinfo.output_width; x++) {
+                                       for (x = 0; x < destination_width; x++) {
                                                if (srcinfo.saw_Adobe_marker) {
                                                        c = p_buffer[0];
                                                        m = p_buffer[1];
@@ -352,7 +352,7 @@ _cairo_image_surface_create_from_jpeg (GInputStream  *istream,
 
        case JCS_GRAYSCALE:
                {
-                       while (srcinfo.output_scanline < srcinfo.output_height) {
+                       while (srcinfo.output_scanline < destination_height) {
                                if (g_cancellable_is_cancelled (cancellable))
                                        goto stop_loading;
 
@@ -366,7 +366,7 @@ _cairo_image_surface_create_from_jpeg (GInputStream  *istream,
                                        if (g_cancellable_is_cancelled (cancellable))
                                                goto stop_loading;
 
-                                       for (x = 0; x < srcinfo.output_width; x++) {
+                                       for (x = 0; x < destination_width; x++) {
                                                r = g = b = p_buffer[0];
                                                pixel = CAIRO_RGBA_TO_UINT32 (r, g, b, 0xff);
                                                memcpy (p_surface, &pixel, sizeof (guint32));
@@ -384,7 +384,7 @@ _cairo_image_surface_create_from_jpeg (GInputStream  *istream,
 
        case JCS_RGB:
                {
-                       while (srcinfo.output_scanline < srcinfo.output_height) {
+                       while (srcinfo.output_scanline < destination_height) {
                                if (g_cancellable_is_cancelled (cancellable))
                                        goto stop_loading;
 
@@ -398,7 +398,7 @@ _cairo_image_surface_create_from_jpeg (GInputStream  *istream,
                                        if (g_cancellable_is_cancelled (cancellable))
                                                goto stop_loading;
 
-                                       for (x = 0; x < srcinfo.output_width; x++) {
+                                       for (x = 0; x < destination_width; x++) {
                                                r = p_buffer[0];
                                                g = p_buffer[1];
                                                b = p_buffer[2];
@@ -431,7 +431,7 @@ _cairo_image_surface_create_from_jpeg (GInputStream  *istream,
                        g_cr_tab = YCbCr_G_Cr_Tab;
                        b_cb_tab = YCbCr_B_Cb_Tab;
 
-                       while (srcinfo.output_scanline < srcinfo.output_height) {
+                       while (srcinfo.output_scanline < destination_height) {
                                if (g_cancellable_is_cancelled (cancellable))
                                        goto stop_loading;
 
@@ -445,7 +445,7 @@ _cairo_image_surface_create_from_jpeg (GInputStream  *istream,
                                        if (g_cancellable_is_cancelled (cancellable))
                                                goto stop_loading;
 
-                                       for (x = 0; x < srcinfo.output_width; x++) {
+                                       for (x = 0; x < destination_width; x++) {
                                                Y = p_buffer[0];
                                                Cb = p_buffer[1];
                                                Cr = p_buffer[2];
@@ -486,7 +486,7 @@ _cairo_image_surface_create_from_jpeg (GInputStream  *istream,
                        CMYK_table_init ();
                        cmyk_tab = CMYK_Tab;
 
-                       while (srcinfo.output_scanline < srcinfo.output_height) {
+                       while (srcinfo.output_scanline < destination_height) {
                                if (g_cancellable_is_cancelled (cancellable))
                                        goto stop_loading;
 
@@ -500,7 +500,7 @@ _cairo_image_surface_create_from_jpeg (GInputStream  *istream,
                                        if (g_cancellable_is_cancelled (cancellable))
                                                goto stop_loading;
 
-                                       for (x = 0; x < srcinfo.output_width; x++) {
+                                       for (x = 0; x < destination_width; x++) {
                                                Y = p_buffer[0];
                                                Cb = p_buffer[1];
                                                Cr = p_buffer[2];