X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Ftaskstats.c;h=4c3476fa058d5627650779f0559dc17c3a7cb1b8;hb=2fb90b128aaf7758e3de22119515fb11174d4f23;hp=d2a41339f37bd0b7722aba407ca04e98c372660d;hpb=68062b86fc0f480b806d270a8278709a5a41bb67;p=linux-2.6

diff --git a/kernel/taskstats.c b/kernel/taskstats.c
index d2a41339f3..4c3476fa05 100644
--- a/kernel/taskstats.c
+++ b/kernel/taskstats.c
@@ -69,7 +69,7 @@ enum actions {
 };
 
 static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp,
-			void **replyp, size_t size)
+				size_t size)
 {
 	struct sk_buff *skb;
 	void *reply;
@@ -94,7 +94,6 @@ static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp,
 	}
 
 	*skbp = skb;
-	*replyp = reply;
 	return 0;
 }
 
@@ -185,6 +184,7 @@ static int fill_pid(pid_t pid, struct task_struct *tsk,
 	} else
 		get_task_struct(tsk);
 
+	memset(stats, 0, sizeof(*stats));
 	/*
 	 * Each accounting subsystem adds calls to its functions to
 	 * fill in relevant parts of struct taskstsats as follows
@@ -227,6 +227,8 @@ static int fill_tgid(pid_t tgid, struct task_struct *first,
 
 	if (first->signal->stats)
 		memcpy(stats, first->signal->stats, sizeof(*stats));
+	else
+		memset(stats, 0, sizeof(*stats));
 
 	tsk = first;
 	do {
@@ -343,31 +345,35 @@ static int parse(struct nlattr *na, cpumask_t *mask)
 	return ret;
 }
 
-static int mk_reply(struct sk_buff *skb, int type, u32 pid, struct taskstats *stats)
+static struct taskstats *mk_reply(struct sk_buff *skb, int type, u32 pid)
 {
-	struct nlattr *na;
+	struct nlattr *na, *ret;
 	int aggr;
 
-	aggr = TASKSTATS_TYPE_AGGR_TGID;
-	if (type == TASKSTATS_TYPE_PID)
-		aggr = TASKSTATS_TYPE_AGGR_PID;
+	aggr = (type == TASKSTATS_TYPE_PID)
+			? TASKSTATS_TYPE_AGGR_PID
+			: TASKSTATS_TYPE_AGGR_TGID;
 
 	na = nla_nest_start(skb, aggr);
-	NLA_PUT_U32(skb, type, pid);
-	NLA_PUT_TYPE(skb, struct taskstats, TASKSTATS_TYPE_STATS, *stats);
+	if (!na)
+		goto err;
+	if (nla_put(skb, type, sizeof(pid), &pid) < 0)
+		goto err;
+	ret = nla_reserve(skb, TASKSTATS_TYPE_STATS, sizeof(struct taskstats));
+	if (!ret)
+		goto err;
 	nla_nest_end(skb, na);
 
-	return 0;
-nla_put_failure:
-	return -1;
+	return nla_data(ret);
+err:
+	return NULL;
 }
 
 static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
 {
 	int rc = 0;
 	struct sk_buff *rep_skb;
-	struct taskstats stats;
-	void *reply;
+	struct taskstats *stats;
 	size_t size;
 	cpumask_t mask;
 
@@ -389,36 +395,33 @@ static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
 	size = nla_total_size(sizeof(u32)) +
 		nla_total_size(sizeof(struct taskstats)) + nla_total_size(0);
 
-	memset(&stats, 0, sizeof(stats));
-	rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, &reply, size);
+	rc = prepare_reply(info, TASKSTATS_CMD_NEW, &rep_skb, size);
 	if (rc < 0)
 		return rc;
 
+	rc = -EINVAL;
 	if (info->attrs[TASKSTATS_CMD_ATTR_PID]) {
 		u32 pid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_PID]);
-		rc = fill_pid(pid, NULL, &stats);
-		if (rc < 0)
+		stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, pid);
+		if (!stats)
 			goto err;
 
-		if (mk_reply(rep_skb, TASKSTATS_TYPE_PID, pid, &stats))
-			goto nla_put_failure;
+		rc = fill_pid(pid, NULL, stats);
+		if (rc < 0)
+			goto err;
 	} else if (info->attrs[TASKSTATS_CMD_ATTR_TGID]) {
 		u32 tgid = nla_get_u32(info->attrs[TASKSTATS_CMD_ATTR_TGID]);
-		rc = fill_tgid(tgid, NULL, &stats);
-		if (rc < 0)
+		stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tgid);
+		if (!stats)
 			goto err;
 
-		if (mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tgid, &stats))
-			goto nla_put_failure;
-	} else {
-		rc = -EINVAL;
+		rc = fill_tgid(tgid, NULL, stats);
+		if (rc < 0)
+			goto err;
+	} else
 		goto err;
-	}
 
 	return send_reply(rep_skb, info->snd_pid);
-
-nla_put_failure:
-	rc = genlmsg_cancel(rep_skb, reply);
 err:
 	nlmsg_free(rep_skb);
 	return rc;
@@ -453,9 +456,8 @@ void taskstats_exit(struct task_struct *tsk, int group_dead)
 {
 	int rc;
 	struct listener_list *listeners;
-	struct taskstats *tidstats;
+	struct taskstats *stats;
 	struct sk_buff *rep_skb;
-	void *reply;
 	size_t size;
 	int is_thread_group;
 
@@ -480,20 +482,17 @@ void taskstats_exit(struct task_struct *tsk, int group_dead)
 	if (list_empty(&listeners->list))
 		return;
 
-	tidstats = kmem_cache_zalloc(taskstats_cache, GFP_KERNEL);
-	if (!tidstats)
+	rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, size);
+	if (rc < 0)
 		return;
 
-	rc = prepare_reply(NULL, TASKSTATS_CMD_NEW, &rep_skb, &reply, size);
-	if (rc < 0)
-		goto free_stats;
+	stats = mk_reply(rep_skb, TASKSTATS_TYPE_PID, tsk->pid);
+	if (!stats)
+		goto err;
 
-	rc = fill_pid(tsk->pid, tsk, tidstats);
+	rc = fill_pid(tsk->pid, tsk, stats);
 	if (rc < 0)
-		goto err_skb;
-
-	if (mk_reply(rep_skb, TASKSTATS_TYPE_PID, tsk->pid, tidstats))
-		goto nla_put_failure;
+		goto err;
 
 	/*
 	 * Doesn't matter if tsk is the leader or the last group member leaving
@@ -501,20 +500,17 @@ void taskstats_exit(struct task_struct *tsk, int group_dead)
 	if (!is_thread_group || !group_dead)
 		goto send;
 
-	if (mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tsk->tgid, tsk->signal->stats))
-		goto nla_put_failure;
+	stats = mk_reply(rep_skb, TASKSTATS_TYPE_TGID, tsk->tgid);
+	if (!stats)
+		goto err;
+
+	memcpy(stats, tsk->signal->stats, sizeof(*stats));
 
 send:
 	send_cpu_listeners(rep_skb, listeners);
-free_stats:
-	kmem_cache_free(taskstats_cache, tidstats);
 	return;
-
-nla_put_failure:
-	genlmsg_cancel(rep_skb, reply);
-err_skb:
+err:
 	nlmsg_free(rep_skb);
-	goto free_stats;
 }
 
 static struct genl_ops taskstats_ops = {