4.4-stable review patch. If anyone has any objections, please let me know.
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From: Sowmini Varadhan sowmini.varadhan@oracle.com
[ Upstream commit 7ae0c649c47f1c5d2db8cee6dd75855970af1669 ]
If the rds_sock is not added to the bind_hash_table, we must reset rs_bound_addr so that rds_remove_bound will not trip on this rds_sock.
rds_add_bound() does a rds_sock_put() in this failure path, so failing to reset rs_bound_addr will result in a socket refcount bug, and will trigger a WARN_ON with the stack shown below when the application subsequently tries to close the PF_RDS socket.
WARNING: CPU: 20 PID: 19499 at net/rds/af_rds.c:496 \ rds_sock_destruct+0x15/0x30 [rds] : __sk_destruct+0x21/0x190 rds_remove_bound.part.13+0xb6/0x140 [rds] rds_release+0x71/0x120 [rds] sock_release+0x1a/0x70 sock_close+0xe/0x20 __fput+0xd5/0x210 task_work_run+0x82/0xa0 do_exit+0x2ce/0xb30 ? syscall_trace_enter+0x1cc/0x2b0 do_group_exit+0x39/0xa0 SyS_exit_group+0x10/0x10 do_syscall_64+0x61/0x1a0
Signed-off-by: Sowmini Varadhan sowmini.varadhan@oracle.com Acked-by: Santosh Shilimkar santosh.shilimkar@oracle.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/rds/bind.c | 1 + 1 file changed, 1 insertion(+)
--- a/net/rds/bind.c +++ b/net/rds/bind.c @@ -108,6 +108,7 @@ static int rds_add_bound(struct rds_sock rs, &addr, (int)ntohs(*port)); break; } else { + rs->rs_bound_addr = 0; rds_sock_put(rs); ret = -ENOMEM; break;