Merge branch 'stable/for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/ibft

Pull iBFT fix from Konrad Rzeszutek Wilk:
 "One single fix from Chris to workaround UEFI platforms failing with
  iSCSI IBFT"

* 'stable/for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/ibft:
  iscsi_ibft: filter null v4-mapped v6 addresses

1 files changed, 21 insertions, 15 deletions

diff --git a/drivers/firmware/iscsi_ibft.c b/drivers/firmware/iscsi_ibft.c
index 071c2c969eec..72791232e46b 100644
--- a/drivers/firmware/iscsi_ibft.c
+++ b/drivers/firmware/iscsi_ibft.c
@@ -186,8 +186,20 @@ struct ibft_kobject {
 
 static struct iscsi_boot_kset *boot_kset;
 
+/* fully null address */
 static const char nulls[16];
 
+/* IPv4-mapped IPv6 ::ffff:0.0.0.0 */
+static const char mapped_nulls[16] = { 0x00, 0x00, 0x00, 0x00,
+                                       0x00, 0x00, 0x00, 0x00,
+                                       0x00, 0x00, 0xff, 0xff,
+                                       0x00, 0x00, 0x00, 0x00 };
+
+static int address_not_null(u8 *ip)
+{
+	return (memcmp(ip, nulls, 16) && memcmp(ip, mapped_nulls, 16));
+}
+
 /*
  * Helper functions to parse data properly.
  */
@@ -445,7 +457,7 @@ static umode_t ibft_check_nic_for(void *data, int type)
 		rc = S_IRUGO;
 		break;
 	case ISCSI_BOOT_ETH_IP_ADDR:
-		if (memcmp(nic->ip_addr, nulls, sizeof(nic->ip_addr)))
+		if (address_not_null(nic->ip_addr))
 			rc = S_IRUGO;
 		break;
 	case ISCSI_BOOT_ETH_SUBNET_MASK:
@@ -456,21 +468,19 @@ static umode_t ibft_check_nic_for(void *data, int type)
 		rc = S_IRUGO;
 		break;
 	case ISCSI_BOOT_ETH_GATEWAY:
-		if (memcmp(nic->gateway, nulls, sizeof(nic->gateway)))
+		if (address_not_null(nic->gateway))
 			rc = S_IRUGO;
 		break;
 	case ISCSI_BOOT_ETH_PRIMARY_DNS:
-		if (memcmp(nic->primary_dns, nulls,
-			   sizeof(nic->primary_dns)))
+		if (address_not_null(nic->primary_dns))
 			rc = S_IRUGO;
 		break;
 	case ISCSI_BOOT_ETH_SECONDARY_DNS:
-		if (memcmp(nic->secondary_dns, nulls,
-			   sizeof(nic->secondary_dns)))
+		if (address_not_null(nic->secondary_dns))
 			rc = S_IRUGO;
 		break;
 	case ISCSI_BOOT_ETH_DHCP:
-		if (memcmp(nic->dhcp, nulls, sizeof(nic->dhcp)))
+		if (address_not_null(nic->dhcp))
 			rc = S_IRUGO;
 		break;
 	case ISCSI_BOOT_ETH_VLAN:
@@ -536,23 +546,19 @@ static umode_t __init ibft_check_initiator_for(void *data, int type)
 		rc = S_IRUGO;
 		break;
 	case ISCSI_BOOT_INI_ISNS_SERVER:
-		if (memcmp(init->isns_server, nulls,
-			   sizeof(init->isns_server)))
+		if (address_not_null(init->isns_server))
 			rc = S_IRUGO;
 		break;
 	case ISCSI_BOOT_INI_SLP_SERVER:
-		if (memcmp(init->slp_server, nulls,
-			   sizeof(init->slp_server)))
+		if (address_not_null(init->slp_server))
 			rc = S_IRUGO;
 		break;
 	case ISCSI_BOOT_INI_PRI_RADIUS_SERVER:
-		if (memcmp(init->pri_radius_server, nulls,
-			   sizeof(init->pri_radius_server)))
+		if (address_not_null(init->pri_radius_server))
 			rc = S_IRUGO;
 		break;
 	case ISCSI_BOOT_INI_SEC_RADIUS_SERVER:
-		if (memcmp(init->sec_radius_server, nulls,
-			   sizeof(init->sec_radius_server)))
+		if (address_not_null(init->sec_radius_server))
 			rc = S_IRUGO;
 		break;
 	case ISCSI_BOOT_INI_INITIATOR_NAME: