Subject: [merged] fork-unify-and-tighten-up-clone_newuser-clone_newpid-checks.patch removed from -mm tree
To: oleg@xxxxxxxxxx,ebiederm@xxxxxxxxxxxx,luto@xxxxxxxxxxxxxx,walters@xxxxxxxxxx,mm-commits@xxxxxxxxxxxxxxx
From: akpm@xxxxxxxxxxxxxxxxxxxx
Date: Thu, 12 Sep 2013 12:41:13 -0700
The patch titled
Subject: fork: unify and tighten up CLONE_NEWUSER/CLONE_NEWPID checks
has been removed from the -mm tree. Its filename was
fork-unify-and-tighten-up-clone_newuser-clone_newpid-checks.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Oleg Nesterov <oleg@xxxxxxxxxx>
Subject: fork: unify and tighten up CLONE_NEWUSER/CLONE_NEWPID checks
do_fork() denies CLONE_THREAD | CLONE_PARENT if NEWUSER | NEWPID.
Then later copy_process() denies CLONE_SIGHAND if the new process will be
in a different pid namespace (task_active_pid_ns() doesn't match
current->nsproxy->pid_ns).
This looks confusing and inconsistent. CLONE_NEWPID is very similar to
the case when ->pid_ns was already unshared, we want the same restrictions
so copy_process() should also nack CLONE_PARENT.
And it would be better to deny CLONE_NEWUSER && CLONE_SIGHAND as well just
for consistency.
Kill the "CLONE_NEWUSER | CLONE_NEWPID" check in do_fork() and change
copy_process() to do the same check along with ->pid_ns check we already
have.
Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
Acked-by: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Cc: Colin Walters <walters@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
kernel/fork.c | 24 +++++++++---------------
1 file changed, 9 insertions(+), 15 deletions(-)
diff -puN kernel/fork.c~fork-unify-and-tighten-up-clone_newuser-clone_newpid-checks kernel/fork.c
--- a/kernel/fork.c~fork-unify-and-tighten-up-clone_newuser-clone_newpid-checks
+++ a/kernel/fork.c
@@ -1173,13 +1173,16 @@ static struct task_struct *copy_process(
return ERR_PTR(-EINVAL);
/*
- * If the new process will be in a different pid namespace don't
- * allow it to share a thread group or signal handlers with the
- * forking task.
+ * If the new process will be in a different pid or user namespace
+ * do not allow it to share a thread group or signal handlers or
+ * parent with the forking task.
*/
- if ((clone_flags & CLONE_SIGHAND) && (task_active_pid_ns(current) !=
- current->nsproxy->pid_ns_for_children))
- return ERR_PTR(-EINVAL);
+ if (clone_flags & (CLONE_SIGHAND | CLONE_PARENT)) {
+ if ((clone_flags & (CLONE_NEWUSER | CLONE_NEWPID)) ||
+ (task_active_pid_ns(current) !=
+ current->nsproxy->pid_ns_for_children))
+ return ERR_PTR(-EINVAL);
+ }
retval = security_task_create(clone_flags);
if (retval)
@@ -1576,15 +1579,6 @@ long do_fork(unsigned long clone_flags,
long nr;
/*
- * Do some preliminary argument and permissions checking before we
- * actually start allocating stuff
- */
- if (clone_flags & (CLONE_NEWUSER | CLONE_NEWPID)) {
- if (clone_flags & (CLONE_THREAD|CLONE_PARENT))
- return -EINVAL;
- }
-
- /*
* Determine whether and which event to report to ptracer. When
* called from kernel_thread or CLONE_UNTRACED is explicitly
* requested, no event is reported; otherwise, report if the event
_
Patches currently in -mm which might be from oleg@xxxxxxxxxx are
origin.patch
anon_inodefs-forbid-open-via-proc.patch
autofs4-allow-autofs-to-work-outside-the-initial-pid-namespace.patch
autofs4-translate-pids-to-the-right-namespace-for-the-daemon.patch
signals-eventpoll-set-saved_sigmask-at-the-start.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
