From 83e8b87721f21b26b843633caca8ef453e943623 Mon Sep 17 00:00:00 2001 From: Sven Eckelmann Date: Mon, 1 Dec 2014 10:37:28 +0100 Subject: [PATCH] batman-adv: Use only queued fragments when merging MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The fragment queueing code now validates the total_size of each fragment, checks when enough fragments are queued to allow to merge them into a single packet and if the fragments have the correct size. Therefore, it is not required to have any other parameter for the merging function than a list of queued fragments. This change should avoid problems like in the past when the different skb from the list and the function parameter were mixed incorrectly. Signed-off-by: Sven Eckelmann Acked-by: Martin Hundebøll Signed-off-by: Marek Lindner --- net/batman-adv/fragmentation.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/net/batman-adv/fragmentation.c b/net/batman-adv/fragmentation.c index a9fc6537214b..6ce3c84a7e55 100644 --- a/net/batman-adv/fragmentation.c +++ b/net/batman-adv/fragmentation.c @@ -231,19 +231,13 @@ err: * Returns the merged skb or NULL on error. */ static struct sk_buff * -batadv_frag_merge_packets(struct hlist_head *chain, struct sk_buff *skb) +batadv_frag_merge_packets(struct hlist_head *chain) { struct batadv_frag_packet *packet; struct batadv_frag_list_entry *entry; struct sk_buff *skb_out = NULL; int size, hdr_size = sizeof(struct batadv_frag_packet); - /* Make sure incoming skb has non-bogus data. */ - packet = (struct batadv_frag_packet *)skb->data; - size = ntohs(packet->total_size); - if (size > batadv_frag_size_limit()) - goto free; - /* Remove first entry, as this is the destination for the rest of the * fragments. */ @@ -252,6 +246,9 @@ batadv_frag_merge_packets(struct hlist_head *chain, struct sk_buff *skb) skb_out = entry->skb; kfree(entry); + packet = (struct batadv_frag_packet *)skb_out->data; + size = ntohs(packet->total_size); + /* Make room for the rest of the fragments. */ if (pskb_expand_head(skb_out, 0, size - skb_out->len, GFP_ATOMIC) < 0) { kfree_skb(skb_out); @@ -307,7 +304,7 @@ bool batadv_frag_skb_buffer(struct sk_buff **skb, if (hlist_empty(&head)) goto out; - skb_out = batadv_frag_merge_packets(&head, *skb); + skb_out = batadv_frag_merge_packets(&head); if (!skb_out) goto out_err; -- 2.20.1