[PATCH 4.9 27/61] ALSA: asihpi: Hardening for potential Spectre v1
From: Greg Kroah-Hartman
Date: Mon Apr 30 2018 - 15:26:38 EST
4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Takashi Iwai <tiwai@xxxxxxx>
commit f9d94b57e30fd1575b4935045b32d738668aa74b upstream.
As recently Smatch suggested, a couple of places in ASIHPI driver may
expand the array directly from the user-space value with speculation:
sound/pci/asihpi/hpimsginit.c:70 hpi_init_response() warn: potential spectre issue 'res_size' (local cap)
sound/pci/asihpi/hpioctl.c:189 asihpi_hpi_ioctl() warn: potential spectre issue 'adapters'
This patch puts array_index_nospec() for hardening against them.
BugLink: https://marc.info/?l=linux-kernel&m=152411496503418&w=2
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
sound/pci/asihpi/hpimsginit.c | 13 +++++++++----
sound/pci/asihpi/hpioctl.c | 4 +++-
2 files changed, 12 insertions(+), 5 deletions(-)
--- a/sound/pci/asihpi/hpimsginit.c
+++ b/sound/pci/asihpi/hpimsginit.c
@@ -23,6 +23,7 @@
#include "hpi_internal.h"
#include "hpimsginit.h"
+#include <linux/nospec.h>
/* The actual message size for each object type */
static u16 msg_size[HPI_OBJ_MAXINDEX + 1] = HPI_MESSAGE_SIZE_BY_OBJECT;
@@ -39,10 +40,12 @@ static void hpi_init_message(struct hpi_
{
u16 size;
- if ((object > 0) && (object <= HPI_OBJ_MAXINDEX))
+ if ((object > 0) && (object <= HPI_OBJ_MAXINDEX)) {
+ object = array_index_nospec(object, HPI_OBJ_MAXINDEX + 1);
size = msg_size[object];
- else
+ } else {
size = sizeof(*phm);
+ }
memset(phm, 0, size);
phm->size = size;
@@ -66,10 +69,12 @@ void hpi_init_response(struct hpi_respon
{
u16 size;
- if ((object > 0) && (object <= HPI_OBJ_MAXINDEX))
+ if ((object > 0) && (object <= HPI_OBJ_MAXINDEX)) {
+ object = array_index_nospec(object, HPI_OBJ_MAXINDEX + 1);
size = res_size[object];
- else
+ } else {
size = sizeof(*phr);
+ }
memset(phr, 0, sizeof(*phr));
phr->size = size;
--- a/sound/pci/asihpi/hpioctl.c
+++ b/sound/pci/asihpi/hpioctl.c
@@ -33,6 +33,7 @@
#include <linux/stringify.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
+#include <linux/nospec.h>
#ifdef MODULE_FIRMWARE
MODULE_FIRMWARE("asihpi/dsp5000.bin");
@@ -182,7 +183,8 @@ long asihpi_hpi_ioctl(struct file *file,
struct hpi_adapter *pa = NULL;
if (hm->h.adapter_index < ARRAY_SIZE(adapters))
- pa = &adapters[hm->h.adapter_index];
+ pa = &adapters[array_index_nospec(hm->h.adapter_index,
+ ARRAY_SIZE(adapters))];
if (!pa || !pa->adapter || !pa->adapter->type) {
hpi_init_response(&hr->r0, hm->h.object,