pasta: do not leak netlink sock into child

When spawning a child command with pasta command... pasta should not
leak fds that it opened. Only the fds that were already open should be
given to the child.

Run `pasta --config-net -- ls -l /proc/self/fd` from a terminal where
only stdin/out/err are open. The fd 3 was opend by ls to read the
/proc/self/fd dir. But fd 5 is the netlink socket that was opend in
pasta. To prevent such a leak we will open the socket with SOCK_CLOEXEC.

Signed-off-by: Paul Holzinger <pholzing@redhat.com>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
This commit is contained in:
Paul Holzinger 2023-02-07 16:10:46 +01:00 committed by Stefano Brivio
parent 7a8ed9459d
commit 3487b5fc93

View file

@ -56,8 +56,8 @@ static int nl_sock_init_do(void *arg)
if (arg)
ns_enter((struct ctx *)arg);
if (((*s) = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE)) < 0 ||
bind(*s, (struct sockaddr *)&addr, sizeof(addr))) {
*s = socket(AF_NETLINK, SOCK_RAW | SOCK_CLOEXEC, NETLINK_ROUTE);
if (*s < 0 || bind(*s, (struct sockaddr *)&addr, sizeof(addr))) {
*s = -1;
return 0;
}