Message ID | 4A08640D.7020100@nortel.com |
---|---|
State | Accepted, archived |
Delegated to: | David Miller |
Headers | show |
From: "Chris Friesen" <cfriesen@nortel.com> Date: Mon, 11 May 2009 11:44:45 -0600 > If a DHCP server is delayed, it's possible for the client to receive the > DHCPOFFER after it has already sent out a new DHCPDISCOVER message from > a second interface. The client then sends out a DHCPREQUEST from the > second interface, but the server doesn't recognize the device and > rejects the request. > > This patch simply tracks the current device being configured and throws > away the OFFER if it is not intended for the current device. A more > sophisticated approach would be to put the OFFER information into the > struct ic_device rather than storing it globally. > > Signed-off-by: Chris Friesen <cfriesen@nortel.com> Applied, thanks Chris. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/ipv4/ipconfig.c b/net/ipv4/ipconfig.c index 90d22ae..88bf051 100644 --- a/net/ipv4/ipconfig.c +++ b/net/ipv4/ipconfig.c @@ -139,6 +139,8 @@ __be32 ic_servaddr = NONE; /* Boot server IP address */ __be32 root_server_addr = NONE; /* Address of NFS server */ u8 root_server_path[256] = { 0, }; /* Path to mount as root */ +u32 ic_dev_xid; /* Device under configuration */ + /* vendor class identifier */ static char vendor_class_identifier[253] __initdata; @@ -932,6 +934,13 @@ static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, str goto drop_unlock; } + /* Is it a reply for the device we are configuring? */ + if (b->xid != ic_dev_xid) { + if (net_ratelimit()) + printk(KERN_ERR "DHCP/BOOTP: Ignoring delayed packet \n"); + goto drop_unlock; + } + /* Parse extensions */ if (ext_len >= 4 && !memcmp(b->exten, ic_bootp_cookie, 4)) { /* Check magic cookie */ @@ -1115,6 +1124,9 @@ static int __init ic_dynamic(void) get_random_bytes(&timeout, sizeof(timeout)); timeout = CONF_BASE_TIMEOUT + (timeout % (unsigned) CONF_TIMEOUT_RANDOM); for (;;) { + /* Track the device we are configuring */ + ic_dev_xid = d->xid; + #ifdef IPCONFIG_BOOTP if (do_bootp && (d->able & IC_BOOTP)) ic_bootp_send_if(d, jiffies - start_jiffies);