[Mesa-dev] [PATCH] mesa: Add null pointer checks before dereferencing

[Anuj Phogat]

Assertions are not sufficient to check for null pointers as they don't
show up in release builds. So, add explicit null pointer checks in the
code.

Signed-off-by: Anuj Phogat <anuj.phogat at gmail.com>
---
 src/mesa/program/prog_execute.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/mesa/program/prog_execute.c b/src/mesa/program/prog_execute.c
index b902006..1bcbf6b 100644
--- a/src/mesa/program/prog_execute.c
+++ b/src/mesa/program/prog_execute.c
@@ -200,6 +200,8 @@ fetch_vector4(const struct prog_src_register *source,
 {
    const GLfloat *src = get_src_register_pointer(source, machine);
    ASSERT(src);
+   if (src == NULL)
+      return;
 
    if (source->Swizzle == SWIZZLE_NOOP) {
       /* no swizzling */
@@ -303,6 +305,8 @@ fetch_vector1(const struct prog_src_register *source,
 {
    const GLfloat *src = get_src_register_pointer(source, machine);
    ASSERT(src);
+   if (src == NULL)
+      return;
 
    result[0] = src[GET_SWZ(source->Swizzle, 0)];
 
@@ -320,6 +324,9 @@ fetch_vector1ui(const struct prog_src_register *source,
                 const struct gl_program_machine *machine)
 {
    const GLuint *src = (GLuint *) get_src_register_pointer(source, machine);
+   ASSERT(src);
+   if (src == NULL)
+      return 0;
    return src[GET_SWZ(source->Swizzle, 0)];
 }
 
@@ -1439,8 +1446,11 @@ _mesa_execute_program(struct gl_context * ctx,
          {
             const struct prog_src_register *source = &inst->SrcReg[0];
             const GLfloat *src = get_src_register_pointer(source, machine);
+            ASSERT(src);
             GLfloat result[4];
             GLuint i;
+            if (src == NULL)
+               return GL_FALSE;
             for (i = 0; i < 4; i++) {
                const GLuint swz = GET_SWZ(source->Swizzle, i);
                if (swz == SWIZZLE_ZERO)
-- 
1.8.1.4