diff options
Diffstat (limited to 'net/batman-adv/fragmentation.c')
| -rw-r--r-- | net/batman-adv/fragmentation.c | 54 |
1 files changed, 34 insertions, 20 deletions
diff --git a/net/batman-adv/fragmentation.c b/net/batman-adv/fragmentation.c index 7cad97644d05..c120c7c6d25f 100644 --- a/net/batman-adv/fragmentation.c +++ b/net/batman-adv/fragmentation.c @@ -1,5 +1,5 @@ // SPDX-License-Identifier: GPL-2.0 -/* Copyright (C) 2013-2020 B.A.T.M.A.N. contributors: +/* Copyright (C) B.A.T.M.A.N. contributors: * * Martin Hundebøll <martin@hundeboll.net> */ @@ -14,8 +14,8 @@ #include <linux/gfp.h> #include <linux/if_ether.h> #include <linux/jiffies.h> -#include <linux/kernel.h> #include <linux/lockdep.h> +#include <linux/minmax.h> #include <linux/netdevice.h> #include <linux/skbuff.h> #include <linux/slab.h> @@ -27,7 +27,6 @@ #include "originator.h" #include "routing.h" #include "send.h" -#include "soft-interface.h" /** * batadv_frag_clear_chain() - delete entries in the fragment buffer chain @@ -102,8 +101,8 @@ static int batadv_frag_size_limit(void) * * Caller must hold chain->lock. * - * Return: true if chain is empty and caller can just insert the new fragment - * without searching for the right position. + * Return: true if chain is empty and the caller can just insert the new + * fragment without searching for the right position. */ static bool batadv_frag_init_chain(struct batadv_frag_table_entry *chain, u16 seqno) @@ -306,7 +305,7 @@ free: * set *skb to merged packet; 2) Packet is buffered: Return true and set *skb * to NULL; 3) Error: Return false and free skb. * - * Return: true when packet is merged or buffered, false when skb is not not + * Return: true when the packet is merged or buffered, false when skb is not * used. */ bool batadv_frag_skb_buffer(struct sk_buff **skb, @@ -382,15 +381,14 @@ bool batadv_frag_skb_fwd(struct sk_buff *skb, } out: - if (orig_node_dst) - batadv_orig_node_put(orig_node_dst); - if (neigh_node) - batadv_neigh_node_put(neigh_node); + batadv_orig_node_put(orig_node_dst); + batadv_neigh_node_put(neigh_node); return ret; } /** * batadv_frag_create() - create a fragment from skb + * @net_dev: outgoing device for fragment * @skb: skb to create fragment from * @frag_head: header to use in new fragment * @fragment_size: size of new fragment @@ -401,22 +399,25 @@ out: * * Return: the new fragment, NULL on error. */ -static struct sk_buff *batadv_frag_create(struct sk_buff *skb, +static struct sk_buff *batadv_frag_create(struct net_device *net_dev, + struct sk_buff *skb, struct batadv_frag_packet *frag_head, unsigned int fragment_size) { + unsigned int ll_reserved = LL_RESERVED_SPACE(net_dev); + unsigned int tailroom = net_dev->needed_tailroom; struct sk_buff *skb_fragment; unsigned int header_size = sizeof(*frag_head); unsigned int mtu = fragment_size + header_size; - skb_fragment = netdev_alloc_skb(NULL, mtu + ETH_HLEN); + skb_fragment = dev_alloc_skb(ll_reserved + mtu + tailroom); if (!skb_fragment) goto err; skb_fragment->priority = skb->priority; /* Eat the last mtu-bytes of the skb */ - skb_reserve(skb_fragment, header_size + ETH_HLEN); + skb_reserve(skb_fragment, ll_reserved + header_size); skb_split(skb, skb_fragment, skb->len - fragment_size); /* Add the header */ @@ -439,11 +440,12 @@ int batadv_frag_send_packet(struct sk_buff *skb, struct batadv_orig_node *orig_node, struct batadv_neigh_node *neigh_node) { + struct net_device *net_dev = neigh_node->if_incoming->net_dev; struct batadv_priv *bat_priv; struct batadv_hard_iface *primary_if = NULL; struct batadv_frag_packet frag_header; struct sk_buff *skb_fragment; - unsigned int mtu = neigh_node->if_incoming->net_dev->mtu; + unsigned int mtu = net_dev->mtu; unsigned int header_size = sizeof(frag_header); unsigned int max_fragment_size, num_fragments; int ret; @@ -473,6 +475,17 @@ int batadv_frag_send_packet(struct sk_buff *skb, goto free_skb; } + /* GRO might have added fragments to the fragment list instead of + * frags[]. But this is not handled by skb_split and must be + * linearized to avoid incorrect length information after all + * batman-adv fragments were created and submitted to the + * hard-interface + */ + if (skb_has_frag_list(skb) && __skb_linearize(skb)) { + ret = -ENOMEM; + goto free_skb; + } + /* Create one header to be copied to all fragments */ frag_header.packet_type = BATADV_UNICAST_FRAG; frag_header.version = BATADV_COMPAT_VERSION; @@ -503,7 +516,7 @@ int batadv_frag_send_packet(struct sk_buff *skb, goto put_primary_if; } - skb_fragment = batadv_frag_create(skb, &frag_header, + skb_fragment = batadv_frag_create(net_dev, skb, &frag_header, max_fragment_size); if (!skb_fragment) { ret = -ENOMEM; @@ -522,13 +535,14 @@ int batadv_frag_send_packet(struct sk_buff *skb, frag_header.no++; } - /* Make room for the fragment header. */ - if (batadv_skb_head_push(skb, header_size) < 0 || - pskb_expand_head(skb, header_size + ETH_HLEN, 0, GFP_ATOMIC) < 0) { - ret = -ENOMEM; + /* make sure that there is at least enough head for the fragmentation + * and ethernet headers + */ + ret = skb_cow_head(skb, ETH_HLEN + header_size); + if (ret < 0) goto put_primary_if; - } + skb_push(skb, header_size); memcpy(skb->data, &frag_header, header_size); /* Send the last fragment */ |