From f54a65c69be700c5a07ddf53022d72cec5679013 Mon Sep 17 00:00:00 2001
From: Mark Janes <markjanes@swizzler.org>
Date: Fri, 19 Feb 2021 18:18:43 -0800
Subject: [PATCH] intel: check setuid before writing output file in
 INTEL_MEASURE

Without this check, the INTEL_MEASURE environment variable could be
misused to overwrite arbitrary files.

Fixes: 0f4143ec378 ("intel: Print GPU timing data based on INTEL_MEASURE")
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9166>
---
 src/intel/common/intel_measure.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/intel/common/intel_measure.c b/src/intel/common/intel_measure.c
index 51c2145ff18..2c46eb82bd8 100644
--- a/src/intel/common/intel_measure.c
+++ b/src/intel/common/intel_measure.c
@@ -40,6 +40,7 @@
 #include "dev/gen_device_info.h"
 #include "util/debug.h"
 #include "util/macros.h"
+#include "util/u_debug.h"
 
 
 static const struct debug_control debug_control[] = {
@@ -100,7 +101,7 @@ intel_measure_init(struct intel_measure_device *device)
          *sep = '\0';
       }
 
-      if (filename) {
+      if (filename && !__check_suid()) {
          filename += 5;
          config.file = fopen(filename, "w");
          if (!config.file) {