Changeset 20284 in vbox for trunk/src/VBox/HostDrivers/VBoxNetFlt

Timestamp:

Jun 4, 2009 1:39:58 PM (16 years ago)

Author:

vboxsync

Message:

#3783: Tx checksum offloading workaround for CentOS 5.2 (2.6.18).

File:

• trunk/src/VBox/HostDrivers/VBoxNetFlt/linux/VBoxNetFlt-linux.c (modified) (2 diffs)

trunk/src/VBox/HostDrivers/VBoxNetFlt/linux/VBoxNetFlt-linux.c

@@ -658 +658 @@
     {
         if (pBuf->ip_summed == CHECKSUM_PARTIAL && pBuf->pkt_type == PACKET_OUTGOING)
+        {
+#if LINUX_VERSION_CODE == KERNEL_VERSION(2, 6, 18)
+            /*
+             * Try to work around the problem with CentOS 5.2 (2.6.18 kernel),
+             * it passes wrong 'h' pointer down. We take IP header length from
+             * the header itself and reconstruct 'h' pointer to TCP (or whatever)
+             * header.
+             */
+            unsigned char *tmp = pBuf->h.raw;
+            if (pBuf->h == pBuf->nh && pBuf->protocol == htons(ETH_P_IP))
+                pBuf->h.raw = pBuf->nh.raw + ((pBuf->nh.raw[0] & 0xF) * 4);
+#endif /* LINUX_VERSION_CODE == KERNEL_VERSION(2, 6, 18) */
             if (VBOX_SKB_CHECKSUM_HELP(pBuf))
             {
@@ -664 +676 @@
                 return;
             }
+#if LINUX_VERSION_CODE == KERNEL_VERSION(2, 6, 18)
+            /* Restore the original (wrong) pointer. */
+            pBuf->h.raw = tmp;
+#endif /* LINUX_VERSION_CODE == KERNEL_VERSION(2, 6, 18) */
+        }
         vboxNetFltLinuxForwardSegment(pThis, pBuf, fSrc);
     }