Joe.C writes:

 This bug is in busybox 1.0.0-rc2. When using lash exec
builtin with redirection, the opened file fd keep increasing.
For example, please try the following command with lash.

ls -al /proc/<lash pid>/fd
exec /bin/sh 2>/dev/null
ls -al /proc/<lash pid>/fd

  The last 'ls' command output will look like this. The fd
number 4 shouldn't exist.

lrwx------    1 501      100         64 Aug 13 13:56 4 -> /dev/pts/5
l-wx------    1 501      100         64 Aug 13 13:56 2 -> /dev/null
lrwx------    1 501      100         64 Aug 13 13:56 1 -> /dev/pts/5
lrwx------    1 501      100         64 Aug 13 13:56 0 -> /dev/pts/5
dr-xr-xr-x    3 501      100          0 Aug 13 13:56 ..
dr-x------    2 501      100          0 Aug 13 13:56 .

  This one-line patch fix this problem by setting CLOEXEC flag for
squirrel fd. Please apply.

Joe.C

diff --git a/shell/lash.c b/shell/lash.c
index fa416c74261e635ce41250a69b0c44e15cd53966..f454e699084beb1afda05b521a7a54d1c13c5451 100644 (file)
--- a/shell/lash.c
+++ b/shell/lash.c
@@ -656,6 +656,7 @@ static int setup_redirects(struct child_prog *prog, int squirrel[])
                if (openfd != redir->fd) {
                        if (squirrel && redir->fd < 3) {
                                squirrel[redir->fd] = dup(redir->fd);
+                               fcntl (squirrel[redir->fd], F_SETFD, FD_CLOEXEC);
                        }
                        dup2(openfd, redir->fd);
                        close(openfd);