[PATCH 5.2 270/313] mt76: round up length on mt76_wr_copy

From: Greg Kroah-Hartman
Date: Thu Oct 03 2019 - 12:36:13 EST


From: Felix Fietkau <nbd@xxxxxxxx>

commit 850e8f6fbd5d0003b0f1119d19a01c6fef1644e2 upstream.

When beacon length is not a multiple of 4, the beacon could be sent with
the last 1-3 bytes corrupted. The skb data is guaranteed to have enough
room for reading beyond the end, because it is always followed by
skb_shared_info, so rounding up is safe.
All other callers of mt76_wr_copy have multiple-of-4 length already.

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/net/wireless/mediatek/mt76/mmio.c | 2 +-
drivers/net/wireless/mediatek/mt76/usb.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/net/wireless/mediatek/mt76/mmio.c
+++ b/drivers/net/wireless/mediatek/mt76/mmio.c
@@ -43,7 +43,7 @@ static u32 mt76_mmio_rmw(struct mt76_dev
static void mt76_mmio_copy(struct mt76_dev *dev, u32 offset, const void *data,
int len)
{
- __iowrite32_copy(dev->mmio.regs + offset, data, len >> 2);
+ __iowrite32_copy(dev->mmio.regs + offset, data, DIV_ROUND_UP(len, 4));
}

static int mt76_mmio_wr_rp(struct mt76_dev *dev, u32 base,
--- a/drivers/net/wireless/mediatek/mt76/usb.c
+++ b/drivers/net/wireless/mediatek/mt76/usb.c
@@ -164,7 +164,7 @@ static void mt76u_copy(struct mt76_dev *
int i, ret;

mutex_lock(&usb->usb_ctrl_mtx);
- for (i = 0; i < (len / 4); i++) {
+ for (i = 0; i < DIV_ROUND_UP(len, 4); i++) {
put_unaligned_le32(val[i], usb->data);
ret = __mt76u_vendor_request(dev, MT_VEND_MULTI_WRITE,
USB_DIR_OUT | USB_TYPE_VENDOR,