4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Roland Dreier <roland@xxxxxxxxxxxxxxx> commit 09abfe7b5b2f442a85f4c4d59ecf582ad76088d7 upstream. The RDMA CM will select a source device and address by consulting the routing table if no source address is passed into rdma_resolve_address(). Userspace will ask for this by passing an all-zero source address in the RESOLVE_IP command. Unfortunately the new check for non-zero address size rejects this with EINVAL, which breaks valid userspace applications. Fix this by explicitly allowing a zero address family for the source. Fixes: 2975d5de6428 ("RDMA/ucma: Check AF family prior resolving address") Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Roland Dreier <roland@xxxxxxxxxxxxxxx> Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/infiniband/core/ucma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/infiniband/core/ucma.c +++ b/drivers/infiniband/core/ucma.c @@ -676,7 +676,7 @@ static ssize_t ucma_resolve_ip(struct uc if (copy_from_user(&cmd, inbuf, sizeof(cmd))) return -EFAULT; - if (!rdma_addr_size_in6(&cmd.src_addr) || + if ((cmd.src_addr.sin6_family && !rdma_addr_size_in6(&cmd.src_addr)) || !rdma_addr_size_in6(&cmd.dst_addr)) return -EINVAL;