ARM: orion5x: Revert commit 4904dbda41c8.

It is not valid for orion5x to use mac_pton().

First of all, the orion5x buffer is not NULL terminated.  mac_pton()
has no business operating on non-NULL terminated buffers because
only the caller can know that this is valid and in what manner it
is ok to parse this NULL'less buffer.

Second of all, orion5x operates on an __iomem pointer, which cannot
be dereferenced using normal C pointer operations.  Accesses to
such areas much be performed with the proper iomem accessors.

Fixes: 4904dbda41c8 ("ARM: orion5x: use mac_pton() helper")
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 50 insertions, 3 deletions

diff --git a/arch/arm/mach-orion5x/dns323-setup.c b/arch/arm/mach-orion5x/dns323-setup.c
index cd483bfb5ca8..d13344b2ddcd 100644
--- a/arch/arm/mach-orion5x/dns323-setup.c
+++ b/arch/arm/mach-orion5x/dns323-setup.c
@@ -173,10 +173,42 @@ static struct mv643xx_eth_platform_data dns323_eth_data = {
 	.phy_addr = MV643XX_ETH_PHY_ADDR(8),
 };
 
+/* dns323_parse_hex_*() taken from tsx09-common.c; should a common copy of these
+ * functions be kept somewhere?
+ */
+static int __init dns323_parse_hex_nibble(char n)
+{
+	if (n >= '0' && n <= '9')
+		return n - '0';
+
+	if (n >= 'A' && n <= 'F')
+		return n - 'A' + 10;
+
+	if (n >= 'a' && n <= 'f')
+		return n - 'a' + 10;
+
+	return -1;
+}
+
+static int __init dns323_parse_hex_byte(const char *b)
+{
+	int hi;
+	int lo;
+
+	hi = dns323_parse_hex_nibble(b[0]);
+	lo = dns323_parse_hex_nibble(b[1]);
+
+	if (hi < 0 || lo < 0)
+		return -1;
+
+	return (hi << 4) | lo;
+}
+
 static int __init dns323_read_mac_addr(void)
 {
 	u_int8_t addr[6];
-	void __iomem *mac_page;
+	int i;
+	char *mac_page;
 
 	/* MAC address is stored as a regular ol' string in /dev/mtdblock4
 	 * (0x007d0000-0x00800000) starting at offset 196480 (0x2ff80).
@@ -185,8 +217,23 @@ static int __init dns323_read_mac_addr(void)
 	if (!mac_page)
 		return -ENOMEM;
 
-	if (!mac_pton((__force const char *) mac_page, addr))
-		goto error_fail;
+	/* Sanity check the string we're looking at */
+	for (i = 0; i < 5; i++) {
+		if (*(mac_page + (i * 3) + 2) != ':') {
+			goto error_fail;
+		}
+	}
+
+	for (i = 0; i < 6; i++)	{
+		int byte;
+
+		byte = dns323_parse_hex_byte(mac_page + (i * 3));
+		if (byte < 0) {
+			goto error_fail;
+		}
+
+		addr[i] = byte;
+	}
 
 	iounmap(mac_page);
 	printk("DNS-323: Found ethernet MAC address: %pM\n", addr);