From e7914508a549047fae528ad6d5a9987868bae677 Mon Sep 17 00:00:00 2001
From: Jiri Slaby <jslaby@suse.cz>
Date: Wed, 24 Mar 2010 16:11:29 +0100
Subject: [PATCH] --- yaml --- r: 207830 b: refs/heads/master c:
 5b41535aac0c07135ff6a4c5c2ae115d1c20c0bc h: refs/heads/master v: v3

---
 [refs]                         |  2 +-
 trunk/include/linux/resource.h |  4 +-
 trunk/kernel/sys.c             | 71 ++++++++++++++++++----------------
 3 files changed, 40 insertions(+), 37 deletions(-)

diff --git a/[refs] b/[refs]
index 231ba1296589..7df98db48ca5 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 6a1d5e2c85d06da35cdfd93f1a27675bfdc3ad8c
+refs/heads/master: 5b41535aac0c07135ff6a4c5c2ae115d1c20c0bc
diff --git a/trunk/include/linux/resource.h b/trunk/include/linux/resource.h
index 037aa7e6335d..88d36f9145ba 100644
--- a/trunk/include/linux/resource.h
+++ b/trunk/include/linux/resource.h
@@ -80,8 +80,8 @@ struct rlimit64 {
 struct task_struct;
 
 int getrusage(struct task_struct *p, int who, struct rusage __user *ru);
-int do_setrlimit(struct task_struct *tsk, unsigned int resource,
-		struct rlimit *new_rlim);
+int do_prlimit(struct task_struct *tsk, unsigned int resource,
+		struct rlimit *new_rlim, struct rlimit *old_rlim);
 
 #endif /* __KERNEL__ */
 
diff --git a/trunk/kernel/sys.c b/trunk/kernel/sys.c
index c762eebdebf7..bc7d1be0960e 100644
--- a/trunk/kernel/sys.c
+++ b/trunk/kernel/sys.c
@@ -1273,18 +1273,21 @@ SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
 #endif
 
 /* make sure you are allowed to change @tsk limits before calling this */
-int do_setrlimit(struct task_struct *tsk, unsigned int resource,
-		struct rlimit *new_rlim)
+int do_prlimit(struct task_struct *tsk, unsigned int resource,
+		struct rlimit *new_rlim, struct rlimit *old_rlim)
 {
-	struct rlimit *old_rlim;
+	struct rlimit *rlim;
 	int retval = 0;
 
 	if (resource >= RLIM_NLIMITS)
 		return -EINVAL;
-	if (new_rlim->rlim_cur > new_rlim->rlim_max)
-		return -EINVAL;
-	if (resource == RLIMIT_NOFILE && new_rlim->rlim_max > sysctl_nr_open)
-		return -EPERM;
+	if (new_rlim) {
+		if (new_rlim->rlim_cur > new_rlim->rlim_max)
+			return -EINVAL;
+		if (resource == RLIMIT_NOFILE &&
+				new_rlim->rlim_max > sysctl_nr_open)
+			return -EPERM;
+	}
 
 	/* protect tsk->signal and tsk->sighand from disappearing */
 	read_lock(&tasklist_lock);
@@ -1293,42 +1296,42 @@ int do_setrlimit(struct task_struct *tsk, unsigned int resource,
 		goto out;
 	}
 
-	old_rlim = tsk->signal->rlim + resource;
+	rlim = tsk->signal->rlim + resource;
 	task_lock(tsk->group_leader);
-	if (new_rlim->rlim_max > old_rlim->rlim_max &&
-			!capable(CAP_SYS_RESOURCE))
-		retval = -EPERM;
-	if (!retval)
-		retval = security_task_setrlimit(tsk->group_leader, resource,
-				new_rlim);
-
-	if (resource == RLIMIT_CPU && new_rlim->rlim_cur == 0) {
-		/*
-		 * The caller is asking for an immediate RLIMIT_CPU
-		 * expiry.  But we use the zero value to mean "it was
-		 * never set".  So let's cheat and make it one second
-		 * instead
-		 */
-		new_rlim->rlim_cur = 1;
+	if (new_rlim) {
+		if (new_rlim->rlim_max > rlim->rlim_max &&
+				!capable(CAP_SYS_RESOURCE))
+			retval = -EPERM;
+		if (!retval)
+			retval = security_task_setrlimit(tsk->group_leader,
+					resource, new_rlim);
+		if (resource == RLIMIT_CPU && new_rlim->rlim_cur == 0) {
+			/*
+			 * The caller is asking for an immediate RLIMIT_CPU
+			 * expiry.  But we use the zero value to mean "it was
+			 * never set".  So let's cheat and make it one second
+			 * instead
+			 */
+			new_rlim->rlim_cur = 1;
+		}
+	}
+	if (!retval) {
+		if (old_rlim)
+			*old_rlim = *rlim;
+		if (new_rlim)
+			*rlim = *new_rlim;
 	}
-
-	if (!retval)
-		*old_rlim = *new_rlim;
 	task_unlock(tsk->group_leader);
 
-	if (retval || resource != RLIMIT_CPU)
-		goto out;
-
 	/*
 	 * RLIMIT_CPU handling.   Note that the kernel fails to return an error
 	 * code if it rejected the user's attempt to set RLIMIT_CPU.  This is a
 	 * very long-standing error, and fixing it now risks breakage of
 	 * applications, so we live with it
 	 */
-	if (new_rlim->rlim_cur == RLIM_INFINITY)
-		goto out;
-
-	update_rlimit_cpu(tsk, new_rlim->rlim_cur);
+	 if (!retval && new_rlim && resource == RLIMIT_CPU &&
+			 new_rlim->rlim_cur != RLIM_INFINITY)
+		update_rlimit_cpu(tsk, new_rlim->rlim_cur);
 out:
 	read_unlock(&tasklist_lock);
 	return retval;
@@ -1340,7 +1343,7 @@ SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim)
 
 	if (copy_from_user(&new_rlim, rlim, sizeof(*rlim)))
 		return -EFAULT;
-	return do_setrlimit(current, resource, &new_rlim);
+	return do_prlimit(current, resource, &new_rlim, NULL);
 }
 
 /*