Mesa (master): draw: Avoid NULL pointer dereference when binding NULL fragment shaders.

[Jose Fonseca]

Module: Mesa
Branch: master
Commit: edb19707951306447daef43c1ea3cacec5f211fb
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=edb19707951306447daef43c1ea3cacec5f211fb

Author: José Fonseca <jfonseca at vmware.com>
Date:   Thu Feb  2 13:19:56 2012 +0000

draw: Avoid NULL pointer dereference when binding NULL fragment shaders.

Now that the draw module avoids flushing, it may flush precisely when
binding a NULL shader, so care must be taken when restoring the original
fragment shader.

Reviewed-by: Brian Paul <brianp at vmware.com>

---

 src/gallium/auxiliary/draw/draw_pipe_aaline.c   |    2 +-
 src/gallium/auxiliary/draw/draw_pipe_aapoint.c  |    2 +-
 src/gallium/auxiliary/draw/draw_pipe_pstipple.c |    2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/gallium/auxiliary/draw/draw_pipe_aaline.c b/src/gallium/auxiliary/draw/draw_pipe_aaline.c
index 0b368da..ea0a4fb 100644
--- a/src/gallium/auxiliary/draw/draw_pipe_aaline.c
+++ b/src/gallium/auxiliary/draw/draw_pipe_aaline.c
@@ -738,7 +738,7 @@ aaline_flush(struct draw_stage *stage, unsigned flags)
 
    /* restore original frag shader, texture, sampler state */
    draw->suspend_flushing = TRUE;
-   aaline->driver_bind_fs_state(pipe, aaline->fs->driver_fs);
+   aaline->driver_bind_fs_state(pipe, aaline->fs ? aaline->fs->driver_fs : NULL);
    aaline->driver_bind_sampler_states(pipe, aaline->num_samplers,
                                       aaline->state.sampler);
    aaline->driver_set_sampler_views(pipe,
diff --git a/src/gallium/auxiliary/draw/draw_pipe_aapoint.c b/src/gallium/auxiliary/draw/draw_pipe_aapoint.c
index 248f26b..a900dd3 100644
--- a/src/gallium/auxiliary/draw/draw_pipe_aapoint.c
+++ b/src/gallium/auxiliary/draw/draw_pipe_aapoint.c
@@ -744,7 +744,7 @@ aapoint_flush(struct draw_stage *stage, unsigned flags)
 
    /* restore original frag shader */
    draw->suspend_flushing = TRUE;
-   aapoint->driver_bind_fs_state(pipe, aapoint->fs->driver_fs);
+   aapoint->driver_bind_fs_state(pipe, aapoint->fs ? aapoint->fs->driver_fs : NULL);
 
    /* restore original rasterizer state */
    if (draw->rast_handle) {
diff --git a/src/gallium/auxiliary/draw/draw_pipe_pstipple.c b/src/gallium/auxiliary/draw/draw_pipe_pstipple.c
index 0401a45..62c54b3 100644
--- a/src/gallium/auxiliary/draw/draw_pipe_pstipple.c
+++ b/src/gallium/auxiliary/draw/draw_pipe_pstipple.c
@@ -565,7 +565,7 @@ pstip_flush(struct draw_stage *stage, unsigned flags)
 
    /* restore original frag shader, texture, sampler state */
    draw->suspend_flushing = TRUE;
-   pstip->driver_bind_fs_state(pipe, pstip->fs->driver_fs);
+   pstip->driver_bind_fs_state(pipe, pstip->fs ? pstip->fs->driver_fs : NULL);
    pstip->driver_bind_sampler_states(pipe, pstip->num_samplers,
                                      pstip->state.samplers);
    pstip->driver_set_sampler_views(pipe,