From: Nicolai Hähnle Date: Wed, 22 Feb 2017 19:04:39 +0000 (+0100) Subject: st/glsl_to_tgsi: avoid iterating past the head of the instruction list X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=911391bd70fe30ad970c5e56632b2d7ccc29d955;p=mesa.git st/glsl_to_tgsi: avoid iterating past the head of the instruction list exec_node::get_prev() does not guard against going past the beginning of the list, so we need to add explicit checks here. Found by ASAN in piglit arb_shader_storage_buffer_object-rendering. Cc: mesa-stable@lists.freedesktop.org Signed-off-by: Marek Olšák --- diff --git a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp index d43d821aad0..af41bdbbea1 100644 --- a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp +++ b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp @@ -3611,10 +3611,17 @@ glsl_to_tgsi_visitor::visit_ssbo_intrinsic(ir_call *ir) inst->resource = buffer; if (access) inst->buffer_access = access->value.u[0]; + + if (inst == this->instructions.get_head_raw()) + break; inst = (glsl_to_tgsi_instruction *)inst->get_prev(); - if (inst->op == TGSI_OPCODE_UADD) + + if (inst->op == TGSI_OPCODE_UADD) { + if (inst == this->instructions.get_head_raw()) + break; inst = (glsl_to_tgsi_instruction *)inst->get_prev(); - } while (inst && inst->op == op && inst->resource.file == PROGRAM_UNDEFINED); + } + } while (inst->op == op && inst->resource.file == PROGRAM_UNDEFINED); } void