There is a use after free scenario while iterating through the nodes
radix tree despite the ns being a single threaded process. This can
happen when the radix tree APIs are not synchronized with the
rcu_read_lock() APIs.
Convert the radix tree for nodes to xarray to take advantage of the
built in rcu lock usage provided by xarray.
Signed-off-by: Chris Lew <quic_clew@xxxxxxxxxxx>
Signed-off-by: Vignesh Viswanathan <quic_viswanat@xxxxxxxxxxx>
Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxx>
---
net/qrtr/ns.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/net/qrtr/ns.c b/net/qrtr/ns.c
index af28d9e6b53f..b1db0b519179 100644
--- a/net/qrtr/ns.c
+++ b/net/qrtr/ns.c
@@ -16,7 +16,7 @@
#define CREATE_TRACE_POINTS
#include <trace/events/qrtr.h>
-static RADIX_TREE(nodes, GFP_KERNEL);
+static DEFINE_XARRAY(nodes);
static struct {
struct socket *sock;
@@ -73,7 +73,7 @@ static struct qrtr_node *node_get(unsigned int node_id)
{
struct qrtr_node *node;
- node = radix_tree_lookup(&nodes, node_id);
+ node = xa_load(&nodes, node_id);
if (node)
return node;
@@ -85,7 +85,7 @@ static struct qrtr_node *node_get(unsigned int node_id)
node->id = node_id;
xa_init(&node->servers);
- if (radix_tree_insert(&nodes, node_id, node)) {
+ if (xa_store(&nodes, node_id, node, GFP_KERNEL)) {
kfree(node);
return NULL;
}
--
2.41.0
