Bug 704692: Fix gs_memory_t mismatch in cms alloc/free operations.

We generate a cmsContext to use at gs_lib_ctx startup, and then
use that for every call into the cms. This encapsulates the
gs_memory_t.

For gs/pcl/xps etc this works well, as there is only a single
interpreter, hence a single cmsContext.

Unfortunately, for gpdl, each interpreter (potentially) gets its
own cmsContext (certainly, the PS interpreter does). So on startup,
when the PS interpreter initialises, it loads some default profiles
and allocates them with one gs_memory_t. When we then come to read
a profile using another interpreter (in this case, tiff), we read
that using a different gs_memory_t.

Because the icc_cache is stored in the device, it is shared across
all the different interpreters, so we can end up with a mixture of
blocks allocated with different gs_memory_t's. If we stored which
gs_memory_t * had been used to allocate each block with the block
we'd be fine - but we don't.

Accordingly, when we closedown, blocks are 'freed' with the wrong
gs_memory_t, causing problems.

The simplest solution here (short of updating the memory wrappers
that we pass into lcms2/lcms2mt to store gs_memory_t's in every
block, with the attendant memory increase this would cause) is to
move the cmsContext from gs_lib_ctx_t to the gs_lib_ctx core.

In this way we only have a single cmsContext shared across all the
different interpreters. This feels like the correct solution to me.

1 files changed, 7 insertions, 8 deletions

diff --git a/base/gsicc_lcms2.c b/base/gsicc_lcms2.c
index 9badb6dee..3c2d1d579 100644
--- a/base/gsicc_lcms2.c
+++ b/base/gsicc_lcms2.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2001-2021 Artifex Software, Inc.
+/* Copyright (C) 2001-2022 Artifex Software, Inc.
    All Rights Reserved.
 
    This software is provided AS-IS with no warranty, either express or
@@ -731,7 +731,7 @@ gscms_get_link_proof_devlink(gcmmhprofile_t lcms_srchandle,
 }
 
 /* Do any initialization if needed to the CMS */
-int
+void *
 gscms_create(gs_memory_t *memory)
 {
     cmsContext ctx;
@@ -739,27 +739,26 @@ gscms_create(gs_memory_t *memory)
     /* Set our own error handling function */
     ctx = cmsCreateContext((void *)&gs_cms_memhandler, memory);
     if (ctx == NULL)
-        return_error(gs_error_VMerror);
+        return NULL;
 
 #ifdef USE_LCMS2_LOCKING
     cmsPluginTHR(ctx, (void *)&gs_cms_mutexhandler);
 #endif
 
     cmsSetLogErrorHandlerTHR(ctx, gscms_error);
-    gs_lib_ctx_set_cms_context(memory, ctx);
-    return 0;
+
+    return ctx;
 }
 
 /* Do any clean up when done with the CMS if needed */
 void
-gscms_destroy(gs_memory_t *memory)
+gscms_destroy(void *cmsContext_)
 {
-    cmsContext ctx = gs_lib_ctx_get_cms_context(memory);
+    cmsContext ctx = (cmsContext)cmsContext_;
     if (ctx == NULL)
         return;
 
     cmsDeleteContext(ctx);
-    gs_lib_ctx_set_cms_context(memory, NULL);
 }
 
 /* Have the CMS release the link */