[PATCH v3 07/10] sysctl: use generic UUID library

From: Andy Shevchenko
Date: Tue Apr 05 2016 - 09:57:32 EST


UUID library provides uuid_be type and uuid_be_to_bin() function. This
substitutes open coded variant by generic library calls.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
kernel/sysctl_binary.c | 20 ++++++--------------
1 file changed, 6 insertions(+), 14 deletions(-)

diff --git a/kernel/sysctl_binary.c b/kernel/sysctl_binary.c
index 055ad65..ce94c45 100644
--- a/kernel/sysctl_binary.c
+++ b/kernel/sysctl_binary.c
@@ -13,6 +13,7 @@
#include <linux/ctype.h>
#include <linux/netdevice.h>
#include <linux/kernel.h>
+#include <linux/uuid.h>
#include <linux/slab.h>
#include <linux/compat.h>

@@ -1117,9 +1118,8 @@ static ssize_t bin_uuid(struct file *file,

/* Only supports reads */
if (oldval && oldlen) {
- char buf[40], *str = buf;
- unsigned char uuid[16];
- int i;
+ char buf[UUID_STRING_LEN + 1];
+ uuid_be uuid;

result = kernel_read(file, 0, buf, sizeof(buf) - 1);
if (result < 0)
@@ -1128,21 +1128,13 @@ static ssize_t bin_uuid(struct file *file,
buf[result] = '\0';

/* Convert the uuid to from a string to binary */
- for (i = 0; i < 16; i++) {
- if (!isxdigit(str[0]) || !isxdigit(str[1]))
- return -EIO;
-
- uuid[i] = (hex_to_bin(str[0]) << 4) |
- hex_to_bin(str[1]);
- str += 2;
- if (*str == '-')
- str++;
- }
+ if (uuid_be_to_bin(buf, &uuid))
+ return -EIO;

if (oldlen > 16)
oldlen = 16;

- if (copy_to_user(oldval, uuid, oldlen))
+ if (copy_to_user(oldval, &uuid, oldlen))
return -EFAULT;

copied = oldlen;
--
2.8.0.rc3