printk: ipv4 address digits printed in reverse order

put_dec_trunc prints the digits in reverse order and is reversed
inside number(). Continue using put_dec_trunc, but reverse each quad
in ip4_addr_string.

[Noticed by Julius Volz]

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 2 deletions

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index dd7cc7fa3e77..6897724ff5df 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -620,11 +620,15 @@ static char *ip4_addr_string(char *buf, char *end, u8 *addr, int field_width,
                          int precision, int flags)
 {
         char ip4_addr[4 * 4]; /* (4 * 3 decimal digits), 3 dots and trailing zero */
+        char temp[3];   /* hold each IP quad in reverse order */
         char *p = ip4_addr;
-        int i;
+        int i, digits;
 
         for (i = 0; i < 4; i++) {
-                p = put_dec_trunc(p, addr[i]);
+                digits = put_dec_trunc(temp, addr[i]) - temp;
+                /* reverse the digits in the quad */
+                while (digits--)
+                        *p++ = temp[digits];
                 if (i != 3)
                         *p++ = '.';
         }