mesa: don't memcmp() off the end of a cache key.

Reported-by: `per` in #intel-gfx
The size of the cache key varies, so store the actual size as well as
the key blob itself, rather than just assuming it's the same as the size
passed in.

NOTE: This is a candidate for stable branches.

V2: Don't leave silly holes in structure; use unsigned instead of GLuint.
V3: Fix missing case for `last` match.

Signed-off-by: Chris Forbes <chrisf@ijw.co.nz>
Reviewed-by: Paul Berry <stereotype441@gmail.com>

diff --git a/src/mesa/program/prog_cache.c b/src/mesa/program/prog_cache.c
index 47f926b1bc68b9b7c75eab0efb19a184ee7b4d94..1f1c6142dfec332e6b058186d4815497906670df 100644 (file)
--- a/src/mesa/program/prog_cache.c
+++ b/src/mesa/program/prog_cache.c
@@ -37,6 +37,7 @@
 struct cache_item
 {
    GLuint hash;
+   unsigned keysize;
    void *key;
    struct gl_program *program;
    struct cache_item *next;
@@ -174,7 +175,8 @@ struct gl_program *
 _mesa_search_program_cache(struct gl_program_cache *cache,
                            const void *key, GLuint keysize)
 {
-   if (cache->last && 
+   if (cache->last &&
+       cache->last->keysize == keysize &&
        memcmp(cache->last->key, key, keysize) == 0) {
       return cache->last->program;
    }
@@ -183,7 +185,10 @@ _mesa_search_program_cache(struct gl_program_cache *cache,
       struct cache_item *c;
 
       for (c = cache->items[hash % cache->size]; c; c = c->next) {
-         if (c->hash == hash && memcmp(c->key, key, keysize) == 0) {
+         if (c->hash == hash &&
+             c->keysize == keysize &&
+             memcmp(c->key, key, keysize) == 0) {
+
             cache->last = c;
             return c->program;
          }
@@ -207,6 +212,7 @@ _mesa_program_cache_insert(struct gl_context *ctx,
 
    c->key = malloc(keysize);
    memcpy(c->key, key, keysize);
+   c->keysize = keysize;
 
    c->program = program;  /* no refcount change */
 
@@ -235,6 +241,7 @@ _mesa_shader_cache_insert(struct gl_context *ctx,
 
    c->key = malloc(keysize);
    memcpy(c->key, key, keysize);
+   c->keysize = keysize;
 
    c->program = (struct gl_program *)program;  /* no refcount change */