Merge branch 'tr/protect-low-3-fds'

When "git" is spawned in such a way that any of the low 3 file
descriptors is closed, our first open() may yield file descriptor 2,
and writing error message to it would screw things up in a big way.

* tr/protect-low-3-fds:
  git: ensure 0/1/2 are open in main()
  daemon/shell: refactor redirection of 0/1/2 from /dev/null

1 files changed, 3 insertions, 9 deletions

diff --git a/shell.c b/shell.c
index 1429870a8f..66350b220c 100644
--- a/shell.c
+++ b/shell.c
@@ -147,7 +147,6 @@ int main(int argc, char **argv)
 	char *prog;
 	const char **user_argv;
 	struct commands *cmd;
-	int devnull_fd;
 	int count;
 
 	git_setup_gettext();
@@ -156,15 +155,10 @@ int main(int argc, char **argv)
 
 	/*
 	 * Always open file descriptors 0/1/2 to avoid clobbering files
-	 * in die().  It also avoids not messing up when the pipes are
-	 * dup'ed onto stdin/stdout/stderr in the child processes we spawn.
+	 * in die().  It also avoids messing up when the pipes are dup'ed
+	 * onto stdin/stdout/stderr in the child processes we spawn.
 	 */
-	devnull_fd = open("/dev/null", O_RDWR);
-	while (devnull_fd >= 0 && devnull_fd <= 2)
-		devnull_fd = dup(devnull_fd);
-	if (devnull_fd == -1)
-		die_errno("opening /dev/null failed");
-	close (devnull_fd);
+	sanitize_stdfds();
 
 	/*
 	 * Special hack to pretend to be a CVS server