[PATCH] ipconfig.c: fix "dhcp server takes precedence over bootp header one"

[Maxime Bizon <mbizon@xxxxxxxxxx>]

Hello,

I was unable to use nfs root with a dhcp server that does not fill the
"saddr" field in the bootp header (kernel then tries RPC on 0.0.0.0).

The ipconfig code states that the dhcp server_id takes precedence over
bootp header, but I think the check is misplaced as it is done only for
DHCPOFFER.

The following patch fixes the problem.


Signed-off-by: Maxime Bizon <mbizon@xxxxxxxxxx>

--- linux-2.6.13.4/net/ipv4/ipconfig.c.orig     2005-10-18 18:11:54.000000000 
+0200
+++ linux-2.6.13.4/net/ipv4/ipconfig.c  2005-10-18 18:22:18.000000000 +0200
@@ -959,13 +959,6 @@
                                printk(" by server %u.%u.%u.%u\n",
                                       NIPQUAD(ic_servaddr));
 #endif
-                               /* The DHCP indicated server address takes
-                                * precedence over the bootp header one if
-                                * they are different.
-                                */
-                               if ((server_id != INADDR_NONE) &&
-                                   (b->server_ip != server_id))
-                                       b->server_ip = ic_servaddr;
                                break;
 
                        case DHCPACK:
@@ -982,6 +975,14 @@
                                goto drop_unlock;
                        };
 
+                       /* The DHCP indicated server address takes
+                        * precedence over the bootp header one if
+                        * they are different.
+                        */
+                       if ((server_id != INADDR_NONE) &&
+                           (b->server_ip != server_id))
+                               b->server_ip = ic_servaddr;
+
                        ic_dhcp_msgtype = mt;
 
                }

-- 
Maxime