[LEDE-DEV] [PATCH procd] jail: don't always CLONE_NEWUTS

[Etienne CHAMPETIER]

no -h => no CLONE_NEWUTS
-h "" => CLONE_NEWUTS
-h "newjailhostname" => CLONE_NEWUTS + sethostname

Signed-off-by: Etienne CHAMPETIER <champetier.etienne at gmail.com>
---
 jail/jail.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/jail/jail.c b/jail/jail.c
index e425254..c442847 100644
--- a/jail/jail.c
+++ b/jail/jail.c
@@ -244,7 +244,7 @@ static int exec_jail(void *_notused)
 		exit(EXIT_FAILURE);
 	}
 
-	if (opts.namespace && opts.hostname
+	if (opts.namespace && opts.hostname && strlen(opts.hostname) > 0
 			&& sethostname(opts.hostname, strlen(opts.hostname))) {
 		ERROR("sethostname(%s) failed: %s\n", opts.hostname, strerror(errno));
 		exit(EXIT_FAILURE);
@@ -386,9 +386,10 @@ int main(int argc, char **argv)
 
 	uloop_init();
 	if (opts.namespace) {
-		jail_process.pid = clone(exec_jail,
-			child_stack + STACK_SIZE,
-			CLONE_NEWUTS | CLONE_NEWPID | CLONE_NEWNS | CLONE_NEWIPC | SIGCHLD, NULL);
+		int flags = CLONE_NEWPID | CLONE_NEWNS | CLONE_NEWIPC | SIGCHLD;
+		if (opts.hostname)
+			flags |= CLONE_NEWUTS;
+		jail_process.pid = clone(exec_jail, child_stack + STACK_SIZE, flags, NULL);
 	} else {
 		jail_process.pid = fork();
 	}
-- 
1.9.1