Because pledge(2) does not allow us to pass directory file descriptors

around, we can't use file descriptors for the working directory because
we will be unable to pass it to a privileged process to tell it where to
read or write files or spawn children. So move tmux back to using
strings for the current working directory. We try to check it exists
with access() when it is set but ultimately fall back to ~ if it fails
at time of use (or / if that fails too).

1 files changed, 6 insertions, 8 deletions

diff --git a/cmd-attach-session.c b/cmd-attach-session.c
index c570358c..b339b890 100644
--- a/cmd-attach-session.c
+++ b/cmd-attach-session.c
@@ -51,9 +51,8 @@ cmd_attach_session(struct cmd_q *cmdq, const char *tflag, int dflag, int rflag,
 	struct window_pane	*wp = NULL;
 	const char		*update;
 	char			*cause;
-	int			 fd;
 	struct format_tree	*ft;
-	char			*cp;
+	char			*cwd;
 
 	if (RB_EMPTY(&sessions)) {
 		cmdq_error(cmdq, "no sessions");
@@ -97,18 +96,17 @@ cmd_attach_session(struct cmd_q *cmdq, const char *tflag, int dflag, int rflag,
 		ft = format_create();
 		format_defaults(ft, cmd_find_client(cmdq, NULL, 1), s,
 		    NULL, NULL);
-		cp = format_expand(ft, cflag);
+		cwd = format_expand(ft, cflag);
 		format_free(ft);
 
-		fd = open(cp, O_RDONLY|O_DIRECTORY);
-		free(cp);
-		if (fd == -1) {
+		if (access(cwd, X_OK) != 0) {
+			free((void *)cwd);
 			cmdq_error(cmdq, "bad working directory: %s",
 			    strerror(errno));
 			return (CMD_RETURN_ERROR);
 		}
-		close(s->cwd);
-		s->cwd = fd;
+		free((void *)s->cwd);
+		s->cwd = cwd;
 	}
 
 	if (c->session != NULL) {