8382fcac "pidns: Outlaw thread creation after unshare(CLONE_NEWPID)"
nacks CLONE_NEWPID if the forking process unshared pid_ns. This is
correct but unnecessary, copy_pid_ns() does the same check.
Remove the CLONE_NEWPID check to cleanup the code and prepare for
the next change.
Test-case:
static int child(void *arg)
{
return 0;
}
static char stack[16 * 1024];
int main(void)
{
pid_t pid;
assert(unshare(CLONE_NEWUSER | CLONE_NEWPID) == 0);
pid = clone(child, stack + sizeof(stack) / 2,
CLONE_NEWPID | SIGCHLD, NULL);
assert(pid < 0 && errno == EINVAL);
return 0;
}
clone(CLONE_NEWPID) correctly fails with or without this change.
Signed-off-by: Oleg Nesterov <o...@redhat.com>
Acked-by: Andy Lutomirski <l...@amacapital.net>
---
kernel/fork.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/kernel/fork.c b/kernel/fork.c
index 29c9f6b..27b5918 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1177,7 +1177,7 @@ static struct task_struct *copy_process(unsigned long
clone_flags,
* allow it to share a thread group or signal handlers with the
* forking task.
*/
- if ((clone_flags & (CLONE_SIGHAND | CLONE_NEWPID)) &&
+ if ((clone_flags & CLONE_SIGHAND) &&
(task_active_pid_ns(current) != current->nsproxy->pid_ns))
return ERR_PTR(-EINVAL);
--
1.5.5.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
