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Diffstat (limited to 'net/tipc/msg.c')
-rw-r--r--net/tipc/msg.c99
1 files changed, 59 insertions, 40 deletions
diff --git a/net/tipc/msg.c b/net/tipc/msg.c
index 08b4cc7d4..5f7345015 100644
--- a/net/tipc/msg.c
+++ b/net/tipc/msg.c
@@ -121,7 +121,7 @@ int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf)
{
struct sk_buff *head = *headbuf;
struct sk_buff *frag = *buf;
- struct sk_buff *tail;
+ struct sk_buff *tail = NULL;
struct tipc_msg *msg;
u32 fragid;
int delta;
@@ -141,9 +141,15 @@ int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf)
if (unlikely(skb_unclone(frag, GFP_ATOMIC)))
goto err;
head = *headbuf = frag;
- skb_frag_list_init(head);
- TIPC_SKB_CB(head)->tail = NULL;
*buf = NULL;
+ TIPC_SKB_CB(head)->tail = NULL;
+ if (skb_is_nonlinear(head)) {
+ skb_walk_frags(head, tail) {
+ TIPC_SKB_CB(head)->tail = tail;
+ }
+ } else {
+ skb_frag_list_init(head);
+ }
return 0;
}
@@ -463,60 +469,72 @@ bool tipc_msg_make_bundle(struct sk_buff **skb, struct tipc_msg *msg,
/**
* tipc_msg_reverse(): swap source and destination addresses and add error code
- * @buf: buffer containing message to be reversed
- * @dnode: return value: node where to send message after reversal
- * @err: error code to be set in message
- * Consumes buffer if failure
+ * @own_node: originating node id for reversed message
+ * @skb: buffer containing message to be reversed; may be replaced.
+ * @err: error code to be set in message, if any
+ * Consumes buffer at failure
* Returns true if success, otherwise false
*/
-bool tipc_msg_reverse(u32 own_addr, struct sk_buff *buf, u32 *dnode,
- int err)
+bool tipc_msg_reverse(u32 own_node, struct sk_buff **skb, int err)
{
- struct tipc_msg *msg = buf_msg(buf);
+ struct sk_buff *_skb = *skb;
+ struct tipc_msg *hdr = buf_msg(_skb);
struct tipc_msg ohdr;
- uint rdsz = min_t(uint, msg_data_sz(msg), MAX_FORWARD_SIZE);
+ int dlen = min_t(uint, msg_data_sz(hdr), MAX_FORWARD_SIZE);
- if (skb_linearize(buf))
+ if (skb_linearize(_skb))
goto exit;
- msg = buf_msg(buf);
- if (msg_dest_droppable(msg))
+ hdr = buf_msg(_skb);
+ if (msg_dest_droppable(hdr))
goto exit;
- if (msg_errcode(msg))
+ if (msg_errcode(hdr))
goto exit;
- memcpy(&ohdr, msg, msg_hdr_sz(msg));
- msg_set_errcode(msg, err);
- msg_set_origport(msg, msg_destport(&ohdr));
- msg_set_destport(msg, msg_origport(&ohdr));
- msg_set_prevnode(msg, own_addr);
- if (!msg_short(msg)) {
- msg_set_orignode(msg, msg_destnode(&ohdr));
- msg_set_destnode(msg, msg_orignode(&ohdr));
+
+ /* Take a copy of original header before altering message */
+ memcpy(&ohdr, hdr, msg_hdr_sz(hdr));
+
+ /* Never return SHORT header; expand by replacing buffer if necessary */
+ if (msg_short(hdr)) {
+ *skb = tipc_buf_acquire(BASIC_H_SIZE + dlen);
+ if (!*skb)
+ goto exit;
+ memcpy((*skb)->data + BASIC_H_SIZE, msg_data(hdr), dlen);
+ kfree_skb(_skb);
+ _skb = *skb;
+ hdr = buf_msg(_skb);
+ memcpy(hdr, &ohdr, BASIC_H_SIZE);
+ msg_set_hdr_sz(hdr, BASIC_H_SIZE);
}
- msg_set_size(msg, msg_hdr_sz(msg) + rdsz);
- skb_trim(buf, msg_size(msg));
- skb_orphan(buf);
- *dnode = msg_orignode(&ohdr);
+
+ /* Now reverse the concerned fields */
+ msg_set_errcode(hdr, err);
+ msg_set_origport(hdr, msg_destport(&ohdr));
+ msg_set_destport(hdr, msg_origport(&ohdr));
+ msg_set_destnode(hdr, msg_prevnode(&ohdr));
+ msg_set_prevnode(hdr, own_node);
+ msg_set_orignode(hdr, own_node);
+ msg_set_size(hdr, msg_hdr_sz(hdr) + dlen);
+ skb_trim(_skb, msg_size(hdr));
+ skb_orphan(_skb);
return true;
exit:
- kfree_skb(buf);
- *dnode = 0;
+ kfree_skb(_skb);
+ *skb = NULL;
return false;
}
/**
* tipc_msg_lookup_dest(): try to find new destination for named message
* @skb: the buffer containing the message.
- * @dnode: return value: next-hop node, if destination found
- * @err: return value: error code to use, if message to be rejected
+ * @err: error code to be used by caller if lookup fails
* Does not consume buffer
* Returns true if a destination is found, false otherwise
*/
-bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb,
- u32 *dnode, int *err)
+bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, int *err)
{
struct tipc_msg *msg = buf_msg(skb);
- u32 dport;
- u32 own_addr = tipc_own_addr(net);
+ u32 dport, dnode;
+ u32 onode = tipc_own_addr(net);
if (!msg_isdata(msg))
return false;
@@ -527,17 +545,18 @@ bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb,
*err = -TIPC_ERR_NO_NAME;
if (skb_linearize(skb))
return false;
+ msg = buf_msg(skb);
if (msg_reroute_cnt(msg))
return false;
- *dnode = addr_domain(net, msg_lookup_scope(msg));
+ dnode = addr_domain(net, msg_lookup_scope(msg));
dport = tipc_nametbl_translate(net, msg_nametype(msg),
- msg_nameinst(msg), dnode);
+ msg_nameinst(msg), &dnode);
if (!dport)
return false;
msg_incr_reroute_cnt(msg);
- if (*dnode != own_addr)
- msg_set_prevnode(msg, own_addr);
- msg_set_destnode(msg, *dnode);
+ if (dnode != onode)
+ msg_set_prevnode(msg, onode);
+ msg_set_destnode(msg, dnode);
msg_set_destport(msg, dport);
*err = TIPC_OK;
return true;