From e6a59c4bee6ab5da56e3ff6b27a5e16d868d638f Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicm@openbsd.org>
Date: Sun, 25 Sep 2011 18:53:04 +0000
Subject: [PATCH] Reject $SHELL if it is not a full path.

---
 tmux.c   | 4 +++-
 window.c | 2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/tmux.c b/tmux.c
index 196edf6c..5d4fda72 100644
--- a/tmux.c
+++ b/tmux.c
@@ -98,7 +98,9 @@ getshell(void)
 int
 checkshell(const char *shell)
 {
-	if (shell == NULL || *shell == '\0' || areshell(shell))
+	if (shell == NULL || *shell == '\0' || *shell != '/')
+		return (0);
+	if (areshell(shell))
 		return (0);
 	if (access(shell, X_OK) != 0)
 		return (0);
diff --git a/window.c b/window.c
index 0736daeb..4f55c513 100644
--- a/window.c
+++ b/window.c
@@ -697,7 +697,7 @@ window_pane_spawn(struct window_pane *wp, const char *cmd, const char *shell,
 		if (*wp->cmd != '\0') {
 			/* Set SHELL but only if it is currently not useful. */
 			shell = getenv("SHELL");
-			if (shell == NULL || *shell == '\0' || areshell(shell))
+			if (checkshell(shell))
 				setenv("SHELL", wp->shell, 1);
 
 			execl(_PATH_BSHELL, "sh", "-c", wp->cmd, (char *) NULL);