Stuart Henderson writes: > On 2020/04/29 15:13, Jacqueline Jolicoeur wrote: >> Hi, >> >> I have noticed gimp-2.10.18p1 crashes everytime I try to open a file. >> Removing all my GIMP cache and config files has not resolved it. >> >> I am aware this was posted earlier. I wanted to report that this bug still >> exists as of today with the recent snapshots. > > We don't have any ideas yet. I haven't been able to reproduce it recently, > the crash is in gtk+2 in possibly something theme-related so maybe try a > different > theme or try a different window manager or desktop environment and see if that > makes it go away? > > The upstream bug is currently at > https://gitlab.gnome.org/GNOME/gdk-pixbuf/-/issues/148
Here is a diff for x11/gtk+2 to fix GIMP crashing. Feedback and tests are welcome. "Image Data" and "Example 1. put_pixel() example" were useful. https://developer.gimp.org/api/2.0/gdk-pixbuf/gdk-pixbuf-gdk-pixbuf.html Example 1 was very similar to the code in pixbuf-render.c's compute_hint function. https://marc.info/?l=openbsd-ports&m=157538140605480&w=2 I got the same stacktrace as brynet@ posted here. (x0=23, x1=24, y0=31, y1=32.) Some stuff was optimized out but I got it to print by going back to earlier stack frames or by slightly modifying the code with a fix that didn't work (that's how I got num_channels = 3). Given these values of x0, x1, y0, y1 and num_channels it seems like it goes beyond the end of the pixbuf buffer. It was going out of bounds on (n_channels != 4 && a != *(p++)) according to gdb. If anything, num_channels being 3 with my change prevents it from advancing the p pointer too far. RGBA each has a byte for red, green, blue and alpha. In this case, num_channels = 3 so there is no alpha channel. Each row looks like this with possible padding at the end: RGBARGBA... In this case there is no alpha either so it could look like: RGBRGB... rowstride = 72 in this case so there are 72 bytes in each row if (r != *(p++) || g != *(p++) || b != *(p++) || (n_channels != 4 && a != *(p++))) p is positioned to where it wants to compute hints like THEME_CONSTANT_ROWS. I infer that THEME_CONSTANT_ROWS means r = g = b like the grey theme that crashes. The first 2 lines should be sufficient to check r = g = b, so I think that even the last two lines with b and n_channels can be removed. Although, I don't know the exact meaning of THEME_CONSTANT_ROWS and how alpha affects it so this could be something to ask upstream. The last line currently reads: if there is no alpha channel and alpha is not equal to X (where X is RGBAX) then the theme has a false bit for THEME_CONSTANT_ROWS. I think this is incorrect and should say if there _is_ an alpha channel. Testing ======= As others have reported, this was hard to reproduce. To test keep spamming this loop until it crashes. It crashes randomly but within the first ~10 tries on the current version of gtk+2. Edit > Preferences > Themes > Grey Ctrl-O for open file prompt Escape to close Edit > Preferences > Themes > Dark Ctrl-O for open file prompt Escape to close With this patch it no longer crashes in my testing. Index: Makefile =================================================================== RCS file: /cvs/ports/x11/gtk+2/Makefile,v retrieving revision 1.233 diff -u -p -u -p -r1.233 Makefile --- Makefile 10 Nov 2019 21:44:07 -0000 1.233 +++ Makefile 1 May 2020 10:30:50 -0000 @@ -9,7 +9,7 @@ GNOME_PROJECT= gtk+ PKGNAME-main= gtk+2-${GNOME_VERSION} PKGNAME-cups= gtk+2-cups-${GNOME_VERSION} -REVISION-main= 8 +REVISION-main= 9 REVISION-cups= 4 CATEGORIES= x11 devel Index: patches/patch-modules_engines_pixbuf_pixbuf-render_c =================================================================== RCS file: patches/patch-modules_engines_pixbuf_pixbuf-render_c diff -N patches/patch-modules_engines_pixbuf_pixbuf-render_c --- /dev/null 1 Jan 1970 00:00:00 -0000 +++ patches/patch-modules_engines_pixbuf_pixbuf-render_c 1 May 2020 10:30:50 -0000 @@ -0,0 +1,18 @@ +$OpenBSD$ + +fixes https://gitlab.gnome.org/GNOME/gdk-pixbuf/-/issues/148 + +only check for alpha if there is an alpha channel + +Index: modules/engines/pixbuf/pixbuf-render.c +--- modules/engines/pixbuf/pixbuf-render.c.orig ++++ modules/engines/pixbuf/pixbuf-render.c +@@ -603,7 +603,7 @@ compute_hint (GdkPixbuf *pixbuf, + if (r != *(p++) || + g != *(p++) || + b != *(p++) || +- (n_channels != 4 && a != *(p++))) ++ (n_channels == 4 && a != *(p++))) + { + hints &= ~THEME_CONSTANT_ROWS; + if (!(hints & THEME_MISSING))
