Use a private UTS namespace to provide a deterministic host/domain name to builders

In chroot builds, set the host name to "localhost" and the domain name
to "(none)" (the latter being the kernel's default).  This improves
determinism a bit further.

P.S. I have to idea what UTS stands for.
This commit is contained in:
Eelco Dolstra 2012-06-25 14:12:17 -04:00
parent 8da6772ed4
commit 5489086456

View file

@ -1793,7 +1793,7 @@ void DerivationGoal::startBuilder()
IPC mechanisms (shared memory, message queues,
semaphores). It also ensures that all IPC
objects are destroyed when the builder exits. */
if (unshare(CLONE_NEWNS | CLONE_NEWNET | CLONE_NEWIPC) == -1)
if (unshare(CLONE_NEWNS | CLONE_NEWNET | CLONE_NEWIPC | CLONE_NEWUTS) == -1)
throw SysError("cannot set up private namespaces");
/* Initialise the loopback interface. */
@ -1808,6 +1808,12 @@ void DerivationGoal::startBuilder()
fd.close();
/* Set the hostname etc. to fixed values. */
char hostname[] = "localhost";
sethostname(hostname, sizeof(hostname));
char domainname[] = "(none)"; // kernel default
setdomainname(domainname, sizeof(domainname));
/* Bind-mount all the directories from the "host"
filesystem that we want in the chroot
environment. */