switchtec: Fix Spectre v1 vulnerability

[mirror_ubuntu-bionic-kernel.git] / drivers / pci / switch / switchtec.c

diff --git a/drivers/pci/switch/switchtec.c b/drivers/pci/switch/switchtec.c
index 730cc897b94da0251dac161192fd1bf1fc47b324..cc4103b4671b4e5e0d94f0b6df03025003f7af1b 100644 (file)
--- a/drivers/pci/switch/switchtec.c
+++ b/drivers/pci/switch/switchtec.c
@@ -23,6 +23,8 @@
 #include <linux/poll.h>
 #include <linux/wait.h>
 
+#include <linux/nospec.h>
+
 MODULE_DESCRIPTION("Microsemi Switchtec(tm) PCIe Management Driver");
 MODULE_VERSION("0.1");
 MODULE_LICENSE("GPL");
@@ -917,6 +919,8 @@ static int ioctl_port_to_pff(struct switchtec_dev *stdev,
        default:
                if (p.port > ARRAY_SIZE(pcfg->dsp_pff_inst_id))
                        return -EINVAL;
+               p.port = array_index_nospec(p.port,
+                                       ARRAY_SIZE(pcfg->dsp_pff_inst_id) + 1);
                p.pff = ioread32(&pcfg->dsp_pff_inst_id[p.port - 1]);
                break;
        }