From 25a5d69ee6478dd72302b280e11f9ac0ceb9553a Mon Sep 17 00:00:00 2001
From: Amal Raj T <tjarlama@gmail.com>
Date: Wed, 29 Jul 2020 16:57:29 +0530
Subject: [PATCH] fs: clobber req->path on uv_fs_mkstemp() error

Since clobbering expects the string to be in writable area,
uv_fs_mkstemp(NULL, req, "test_file", NULL) will result in
segmentation fault. so the string was moved to stack to make it
writable.

Previous commit also ignored to preserve return code when initial
check in uv_fs_mkstemp fails.

See previous commit for more details
---
 src/unix/fs.c  | 1 +
 test/test-fs.c | 6 +++++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/unix/fs.c b/src/unix/fs.c
index 9a8da0fa3..bcb8e2c5b 100644
--- a/src/unix/fs.c
+++ b/src/unix/fs.c
@@ -306,6 +306,7 @@ static int uv__fs_mkstemp(uv_fs_t* req) {
   if (path_length < pattern_size ||
       strcmp(path + path_length - pattern_size, pattern)) {
     errno = EINVAL;
+    r = -1;
     goto clobber;
   }
 
diff --git a/test/test-fs.c b/test/test-fs.c
index ae9923a9a..26a6afcf0 100644
--- a/test/test-fs.c
+++ b/test/test-fs.c
@@ -1271,6 +1271,7 @@ TEST_IMPL(fs_mkstemp) {
   int r;
   int fd;
   const char path_template[] = "test_file_XXXXXX";
+  const char test_file[] = "test_file";
   uv_fs_t req;
 
   loop = uv_default_loop();
@@ -1290,7 +1291,10 @@ TEST_IMPL(fs_mkstemp) {
   ASSERT(strcmp(mkstemp_req1.path, mkstemp_req2.path) != 0);
 
   /* invalid template returns EINVAL */
-  ASSERT(uv_fs_mkstemp(NULL, &mkstemp_req3, "test_file", NULL) == UV_EINVAL);
+  ASSERT(uv_fs_mkstemp(NULL, &mkstemp_req3, test_file, NULL) == UV_EINVAL);
+
+  /* Make sure that path is empty string */
+  ASSERT(strlen(mkstemp_req3.path) == 0);
 
   /* We can write to the opened file */
   iov = uv_buf_init(test_buf, sizeof(test_buf));