tracing: Convert to kstrtoul_from_user

This patch replaces the code for getting an unsigned long from a
userspace buffer by a simple call to kstroul_from_user.
This makes it easier to read and less error prone.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Link: http://lkml.kernel.org/r/1307476707-14762-1-git-send-email-peterhuewe@gmx.de
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 10 insertions, 55 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index cf22b4bf9896..c977018e87c2 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2706,20 +2706,11 @@ tracing_ctrl_write(struct file *filp, const char __user *ubuf,
                    size_t cnt, loff_t *ppos)
 {
         struct trace_array *tr = filp->private_data;
-        char buf[64];
         unsigned long val;
         int ret;
 
-        if (cnt >= sizeof(buf))
-                return -EINVAL;
-
-        if (copy_from_user(&buf, ubuf, cnt))
-                return -EFAULT;
-
-        buf[cnt] = 0;
-
-        ret = strict_strtoul(buf, 10, &val);
-        if (ret < 0)
+        ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+        if (ret)
                 return ret;
 
         val = !!val;
@@ -3006,20 +2997,11 @@ tracing_max_lat_write(struct file *filp, const char __user *ubuf,
                       size_t cnt, loff_t *ppos)
 {
         unsigned long *ptr = filp->private_data;
-        char buf[64];
         unsigned long val;
         int ret;
 
-        if (cnt >= sizeof(buf))
-                return -EINVAL;
-
-        if (copy_from_user(&buf, ubuf, cnt))
-                return -EFAULT;
-
-        buf[cnt] = 0;
-
-        ret = strict_strtoul(buf, 10, &val);
-        if (ret < 0)
+        ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+        if (ret)
                 return ret;
 
         *ptr = val * 1000;
@@ -3474,19 +3456,10 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
                       size_t cnt, loff_t *ppos)
 {
         unsigned long val;
-        char buf[64];
         int ret;
 
-        if (cnt >= sizeof(buf))
-                return -EINVAL;
-
-        if (copy_from_user(&buf, ubuf, cnt))
-                return -EFAULT;
-
-        buf[cnt] = 0;
-
-        ret = strict_strtoul(buf, 10, &val);
-        if (ret < 0)
+        ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+        if (ret)
                 return ret;
 
         /* must have at least 1 entry */
@@ -4139,19 +4112,10 @@ trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt,
 {
         struct trace_option_dentry *topt = filp->private_data;
         unsigned long val;
-        char buf[64];
         int ret;
 
-        if (cnt >= sizeof(buf))
-                return -EINVAL;
-
-        if (copy_from_user(&buf, ubuf, cnt))
-                return -EFAULT;
-
-        buf[cnt] = 0;
-
-        ret = strict_strtoul(buf, 10, &val);
-        if (ret < 0)
+        ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+        if (ret)
                 return ret;
 
         if (val != 0 && val != 1)
@@ -4199,20 +4163,11 @@ trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt,
                          loff_t *ppos)
 {
         long index = (long)filp->private_data;
-        char buf[64];
         unsigned long val;
         int ret;
 
-        if (cnt >= sizeof(buf))
-                return -EINVAL;
-
-        if (copy_from_user(&buf, ubuf, cnt))
-                return -EFAULT;
-
-        buf[cnt] = 0;
-
-        ret = strict_strtoul(buf, 10, &val);
-        if (ret < 0)
+        ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+        if (ret)
                 return ret;
 
         if (val != 0 && val != 1)