[TIPC]: fix tipc_link_create error handling

if printbuf allocation or tipc_node_attach_link() fails, invalid
references to the link are left in the associated node and bearer
structures.
Fix by allocating printbuf early and moving timer initialization
and the addition of the new link to the b_ptr->links list after
tipc_node_attach_link() succeeded.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/tipc/link.c b/net/tipc/link.c
index 5adfdfd49d61b65dc0164cd1fcecaff88d4fa558..1d674e0848fa4d475cd5a391c4b3c382d83c7de9 100644 (file)
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -423,6 +423,17 @@ struct link *tipc_link_create(struct bearer *b_ptr, const u32 peer,
                return NULL;
        }
 
+       if (LINK_LOG_BUF_SIZE) {
+               char *pb = kmalloc(LINK_LOG_BUF_SIZE, GFP_ATOMIC);
+
+               if (!pb) {
+                       kfree(l_ptr);
+                       warn("Link creation failed, no memory for print buffer\n");
+                       return NULL;
+               }
+               tipc_printbuf_init(&l_ptr->print_buf, pb, LINK_LOG_BUF_SIZE);
+       }
+
        l_ptr->addr = peer;
        if_name = strchr(b_ptr->publ.name, ':') + 1;
        sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:",
@@ -432,8 +443,6 @@ struct link *tipc_link_create(struct bearer *b_ptr, const u32 peer,
                tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
                /* note: peer i/f is appended to link name by reset/activate */
        memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr));
-       k_init_timer(&l_ptr->timer, (Handler)link_timeout, (unsigned long)l_ptr);
-       list_add_tail(&l_ptr->link_list, &b_ptr->links);
        l_ptr->checkpoint = 1;
        l_ptr->b_ptr = b_ptr;
        link_set_supervision_props(l_ptr, b_ptr->media->tolerance);
@@ -459,21 +468,14 @@ struct link *tipc_link_create(struct bearer *b_ptr, const u32 peer,
 
        l_ptr->owner = tipc_node_attach_link(l_ptr);
        if (!l_ptr->owner) {
+               if (LINK_LOG_BUF_SIZE)
+                       kfree(l_ptr->print_buf.buf);
                kfree(l_ptr);
                return NULL;
        }
 
-       if (LINK_LOG_BUF_SIZE) {
-               char *pb = kmalloc(LINK_LOG_BUF_SIZE, GFP_ATOMIC);
-
-               if (!pb) {
-                       kfree(l_ptr);
-                       warn("Link creation failed, no memory for print buffer\n");
-                       return NULL;
-               }
-               tipc_printbuf_init(&l_ptr->print_buf, pb, LINK_LOG_BUF_SIZE);
-       }
-
+       k_init_timer(&l_ptr->timer, (Handler)link_timeout, (unsigned long)l_ptr);
+       list_add_tail(&l_ptr->link_list, &b_ptr->links);
        tipc_k_signal((Handler)tipc_link_start, (unsigned long)l_ptr);
 
        dbg("tipc_link_create(): tolerance = %u,cont intv = %u, abort_limit = %u\n",