From: Carl Huang <cjhuang@xxxxxxxxxxxxxx> [ Upstream commit 28541f3d324f6de1e545e2875283b6cef95c5d36 ] The flow is allocated in qrtr_tx_wait, but not freed when qrtr node is released. (*slot) becomes NULL after radix_tree_iter_delete is called in __qrtr_node_release. The fix is to save (*slot) to a vairable and then free it. This memory leak is catched when kmemleak is enabled in kernel, the report looks like below: unreferenced object 0xffffa0de69e08420 (size 32): comm "kworker/u16:3", pid 176, jiffies 4294918275 (age 82858.876s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 28 84 e0 69 de a0 ff ff ........(..i.... 28 84 e0 69 de a0 ff ff 03 00 00 00 00 00 00 00 (..i............ backtrace: [<00000000e252af0a>] qrtr_node_enqueue+0x38e/0x400 [qrtr] [<000000009cea437f>] qrtr_sendmsg+0x1e0/0x2a0 [qrtr] [<000000008bddbba4>] sock_sendmsg+0x5b/0x60 [<0000000003beb43a>] qmi_send_message.isra.3+0xbe/0x110 [qmi_helpers] [<000000009c9ae7de>] qmi_send_request+0x1c/0x20 [qmi_helpers] Signed-off-by: Carl Huang <cjhuang@xxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/qrtr/qrtr.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/net/qrtr/qrtr.c +++ b/net/qrtr/qrtr.c @@ -166,6 +166,7 @@ static void __qrtr_node_release(struct k { struct qrtr_node *node = container_of(kref, struct qrtr_node, ref); struct radix_tree_iter iter; + struct qrtr_tx_flow *flow; unsigned long flags; void __rcu **slot; @@ -181,8 +182,9 @@ static void __qrtr_node_release(struct k /* Free tx flow counters */ radix_tree_for_each_slot(slot, &node->qrtr_tx_flow, &iter, 0) { + flow = *slot; radix_tree_iter_delete(&node->qrtr_tx_flow, &iter, slot); - kfree(*slot); + kfree(flow); } kfree(node); }