diff options
Diffstat (limited to 'net/appletalk')
| -rw-r--r-- | net/appletalk/ddp.c | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/net/appletalk/ddp.c b/net/appletalk/ddp.c index 16eda21fb38..f6a92a0b7aa 100644 --- a/net/appletalk/ddp.c +++ b/net/appletalk/ddp.c @@ -937,11 +937,11 @@ static unsigned long atalk_sum_partial(const unsigned char *data, static unsigned long atalk_sum_skb(const struct sk_buff *skb, int offset, int len, unsigned long sum) { - int end = skb_headlen(skb); + int start = skb_headlen(skb); int i, copy; /* checksum stuff in header space */ - if ((copy = end - offset) > 0) { + if ( (copy = start - offset) > 0) { if (copy > len) copy = len; sum = atalk_sum_partial(skb->data + offset, copy, sum); @@ -953,9 +953,11 @@ static unsigned long atalk_sum_skb(const struct sk_buff *skb, int offset, /* checksum stuff in frags */ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { - BUG_TRAP(len >= 0); + int end; - end = offset + skb_shinfo(skb)->frags[i].size; + BUG_TRAP(start <= offset + len); + + end = start + skb_shinfo(skb)->frags[i].size; if ((copy = end - offset) > 0) { u8 *vaddr; skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; @@ -963,31 +965,36 @@ static unsigned long atalk_sum_skb(const struct sk_buff *skb, int offset, if (copy > len) copy = len; vaddr = kmap_skb_frag(frag); - sum = atalk_sum_partial(vaddr + frag->page_offset, - copy, sum); + sum = atalk_sum_partial(vaddr + frag->page_offset + + offset - start, copy, sum); kunmap_skb_frag(vaddr); if (!(len -= copy)) return sum; offset += copy; } + start = end; } if (skb_shinfo(skb)->frag_list) { struct sk_buff *list = skb_shinfo(skb)->frag_list; for (; list; list = list->next) { - BUG_TRAP(len >= 0); + int end; + + BUG_TRAP(start <= offset + len); - end = offset + list->len; + end = start + list->len; if ((copy = end - offset) > 0) { if (copy > len) copy = len; - sum = atalk_sum_skb(list, 0, copy, sum); + sum = atalk_sum_skb(list, offset - start, + copy, sum); if ((len -= copy) == 0) return sum; offset += copy; } + start = end; } } |