Subject: [PATCH] More usuable pspace size calculation.
From: Eric W. Biederman <ebiederman@lnxi.com>
Date: 1129746928 -0600

Allocating an arbitrary 1/256 of the nr_pids works but is extremely
arbitrary.  Instead make that the default and use RLIMIT_NPROC
as the size of the pspace to allocate if it is set.

---

 kernel/pid.c |   21 +++++++++++----------
 1 files changed, 11 insertions(+), 10 deletions(-)

53777e560c2b91e830aa44630378c497401ea9f4
diff --git a/kernel/pid.c b/kernel/pid.c
index 4bd186f..2f13c43 100644
--- a/kernel/pid.c
+++ b/kernel/pid.c
@@ -313,17 +313,18 @@ int copy_pspace(int flags, struct task_s
 	if (!(flags & CLONE_NEWPSPACE))
 		return 0;
 
-	/* For now allocate 1/256 of the pidspace */
-	pids = p->pspace->max >> 8;
+	/* Figure out how many pids I can allocate for the pspace */
+	if (p->signal->rlim[RLIMIT_NPROC].rlim_cur != RLIM_INFINITY) {
+		pids = p->signal->rlim[RLIMIT_NPROC].rlim_cur;
+	} else {
+		/* Default to 1/256 of the pspace */
+		pids = p->pspace->max >> 8;
+	}
 
-	/* Verify this could fit in my rlimit */
-	if ((atomic_read(&p->user->processes) + pids) >=
-		p->signal->rlim[RLIMIT_NPROC].rlim_cur) {
-		if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_RESOURCE) &&
-			p->user != &root_user) {
-			put_pspace(p->pspace);
-			return -EAGAIN;
-		}
+	/* Verify I am allocating at least one pid */
+	if (pids < 1) {
+		put_pspace(p->pspace);
+		return -EAGAIN;
 	}
 
 	pid = -1;
-- 
1.0.GIT