Description

In the Linux kernel, the following vulnerability has been resolved: net: fix memory leak in tcp_conn_request() If inet_csk_reqsk_queue_hash_add() return false, tcp_conn_request() will return without free the dst memory, which allocated in af_ops->route_req. Here is the kmemleak stack: unreferenced object 0xffff8881198631c0 (size 240): comm "softirq", pid 0, jiffies 4299266571 (age 1802.392s) hex dump (first 32 bytes): 00 10 9b 03 81 88 ff ff 80 98 da bc ff ff ff ff ................ 81 55 18 bb ff ff ff ff 00 00 00 00 00 00 00 00 .U.............. backtrace: [] kmem_cache_alloc+0x60c/0xa80 [] dst_alloc+0x55/0x250 [] rt_dst_alloc+0x46/0x1d0 [] __mkroute_output+0x29a/0xa50 [] ip_route_output_key_hash+0x10b/0x240 [] ip_route_output_flow+0x1d/0x90 [] inet_csk_route_req+0x2c5/0x500 [] tcp_conn_request+0x691/0x12c0 [] tcp_rcv_state_process+0x3c8/0x11b0 [] tcp_v4_do_rcv+0x156/0x3b0 [] tcp_v4_rcv+0x1cf8/0x1d80 [] ip_protocol_deliver_rcu+0xf6/0x360 [] ip_local_deliver_finish+0xe6/0x1e0 [] ip_local_deliver+0xee/0x360 [] ip_rcv+0xad/0x2f0 [] __netif_receive_skb_one_core+0x123/0x140 Call dst_release() to free the dst memory when inet_csk_reqsk_queue_hash_add() return false in tcp_conn_request().