From f9cecca7a6e3d9ff231075381b88d179e153a5a4 Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Fri, 23 May 2014 14:59:33 -0600 Subject: [PATCH] glsl: fix use-after free bug/crash in ast_declarator_list::hir() The call to get_variable_being_redeclared() may delete 'var' so we can't reference var->name afterward. We fix that by examining the var's name before making that call. Fixes valgrind warnings and possible crash when running the piglit tests/spec/glsl-1.30/execution/clipping/vs-clip-distance-in-param.shader_test test (and probably others). Cc: "10.1 10.2" Reviewed-by: Ian Romanick --- src/glsl/ast_to_hir.cpp | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/src/glsl/ast_to_hir.cpp b/src/glsl/ast_to_hir.cpp index 0128b3f4e82..e06f9b413d2 100644 --- a/src/glsl/ast_to_hir.cpp +++ b/src/glsl/ast_to_hir.cpp @@ -3651,11 +3651,15 @@ ast_declarator_list::hir(exec_list *instructions, * instruction stream. */ exec_list initializer_instructions; + + /* Examine var name here since var may get deleted in the next call */ + bool var_is_gl_id = (strncmp(var->name, "gl_", 3) == 0); + ir_variable *earlier = get_variable_being_redeclared(var, decl->get_location(), state, false /* allow_all_redeclarations */); if (earlier != NULL) { - if (strncmp(var->name, "gl_", 3) == 0 && + if (var_is_gl_id && earlier->data.how_declared == ir_var_declared_in_block) { _mesa_glsl_error(&loc, state, "`%s' has already been redeclared using " -- 2.30.2