tipc: Add missing spinlock in name table display code
This patch ensures that the display code that traverses the
publication lists belonging to a name table entry take its
associated spinlock, to protect against a possible change to
one of its "head of list" pointers caused by a simultaneous
name table lookup operation by another thread of control.
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/tipc/name_table.c b/net/tipc/name_table.c
index 4455f13..096f7bd 100644
--- a/net/tipc/name_table.c
+++ b/net/tipc/name_table.c
@@ -74,7 +74,7 @@
* @first_free: array index of first unused sub-sequence entry
* @ns_list: links to adjacent name sequences in hash chain
* @subscriptions: list of subscriptions for this 'type'
- * @lock: spinlock controlling access to name sequence structure
+ * @lock: spinlock controlling access to publication lists of all sub-sequences
*/
struct name_seq {
@@ -918,7 +918,9 @@
for (sseq = seq->sseqs; sseq != &seq->sseqs[seq->first_free]; sseq++) {
if ((lowbound <= sseq->upper) && (upbound >= sseq->lower)) {
tipc_printf(buf, "%s ", typearea);
+ spin_lock_bh(&seq->lock);
subseq_list(sseq, buf, depth, index);
+ spin_unlock_bh(&seq->lock);
sprintf(typearea, "%10s", " ");
}
}
