From: Nicolai Hähnle Date: Thu, 21 Sep 2017 14:55:35 +0000 (+0200) Subject: st/glsl_to_tgsi: fix a use-after-free in merge_two_dsts X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=2703fa613b674184ad94b077ae68ad04160ba9d5;p=mesa.git st/glsl_to_tgsi: fix a use-after-free in merge_two_dsts Found by address sanitizer. The loop here tries to be safe, but in doing so, it ends up doing exactly the wrong thing: the safe foreach is for when the loop variable (inst) could be deleted and nothing else. However, this particular can delete inst's successor, but not inst itself. Fixes: 8c6a0ebaad72 ("st/mesa: add st fp64 support (v7.1)") Reviewed-by: Marek Olšák Tested-by: Dieter Nützel --- diff --git a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp index 609920a7a87..f4870a1c606 100644 --- a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp +++ b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp @@ -5148,7 +5148,8 @@ glsl_to_tgsi_visitor::eliminate_dead_code(void) void glsl_to_tgsi_visitor::merge_two_dsts(void) { - foreach_in_list_safe(glsl_to_tgsi_instruction, inst, &this->instructions) { + /* We never delete inst, but we may delete its successor. */ + foreach_in_list(glsl_to_tgsi_instruction, inst, &this->instructions) { glsl_to_tgsi_instruction *inst2; bool merged; if (num_inst_dst_regs(inst) != 2)