[Mesa-dev] [PATCH] r600g: Drop references to destroyed blend state

[Michel Dänzer]

From: Michel Dänzer <michel.daenzer at amd.com>

Fixes use-after-free when the currently bound blend state is destroyed.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=85267
Signed-off-by: Michel Dänzer <michel.daenzer at amd.com>
---
 src/gallium/drivers/r600/r600_state_common.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/gallium/drivers/r600/r600_state_common.c b/src/gallium/drivers/r600/r600_state_common.c
index 68365f9..879ec35 100644
--- a/src/gallium/drivers/r600/r600_state_common.c
+++ b/src/gallium/drivers/r600/r600_state_common.c
@@ -158,8 +158,10 @@ static void r600_bind_blend_state(struct pipe_context *ctx, void *state)
 	struct r600_context *rctx = (struct r600_context *)ctx;
 	struct r600_blend_state *blend = (struct r600_blend_state *)state;
 
-	if (blend == NULL)
+	if (blend == NULL) {
+		r600_set_cso_state_with_cb(&rctx->blend_state, NULL, NULL);
 		return;
+	}
 
 	r600_bind_blend_state_internal(rctx, blend, rctx->force_blend_disable);
 }
@@ -447,8 +449,13 @@ static void r600_delete_sampler_state(struct pipe_context *ctx, void *state)
 
 static void r600_delete_blend_state(struct pipe_context *ctx, void *state)
 {
+	struct r600_context *rctx = (struct r600_context *)ctx;
 	struct r600_blend_state *blend = (struct r600_blend_state*)state;
 
+	if (rctx->blend_state.cso == state) {
+		ctx->bind_blend_state(ctx, NULL);
+	}
+
 	r600_release_command_buffer(&blend->buffer);
 	r600_release_command_buffer(&blend->buffer_no_blend);
 	FREE(blend);
-- 
2.1.1