staging: unisys: Linarize skbs

If we can't fit an skb into a frag array, linaraize it so we don't have to

Signed-off-by: Neil Horman <nhorman@redhat.com>
Signed-off-by: Benjamin Romer <benjamin.romer@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/unisys/visornic/visornic_main.c b/drivers/staging/unisys/visornic/visornic_main.c
index f736392..a421a5b 100644 (file)
--- a/drivers/staging/unisys/visornic/visornic_main.c
+++ b/drivers/staging/unisys/visornic/visornic_main.c
@@ -221,9 +221,25 @@ visor_copy_fragsinfo_from_skb(struct sk_buff *skb, unsigned int firstfraglen,
                              struct phys_info frags[])
 {
        unsigned int count = 0, ii, size, offset = 0, numfrags;
+       unsigned int total_count;
 
        numfrags = skb_shinfo(skb)->nr_frags;
 
+       /*
+        * Compute the number of fragments this skb has, and if its more than
+        * frag array can hold, linearize the skb
+        */
+       total_count = numfrags + (firstfraglen / PI_PAGE_SIZE);
+       if (firstfraglen % PI_PAGE_SIZE)
+               total_count++;
+
+       if (total_count > frags_max) {
+               if (skb_linearize(skb))
+                       return -EINVAL;
+               numfrags = skb_shinfo(skb)->nr_frags;
+               firstfraglen = 0;
+       }
+
        while (firstfraglen) {
                if (count == frags_max)
                        return -EINVAL;