The patch below does not apply to the 4.11-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From f9fa0f2bebaa629aff839b7b992298b1fce453d2 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Stefan=20Br=C3=BCns?= <stefan.bruens@xxxxxxxxxxxxxx> Date: Sun, 12 Feb 2017 13:02:13 -0200 Subject: [PATCH] [media] dvb-usb-firmware: don't do DMA on stack MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The buffer allocation for the firmware data was changed in commit 43fab9793c1f ("[media] dvb-usb: don't use stack for firmware load") but the same applies for the reset value. Fixes: 43fab9793c1f ("[media] dvb-usb: don't use stack for firmware load") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Stefan Brüns <stefan.bruens@xxxxxxxxxxxxxx> Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx> diff --git a/drivers/media/usb/dvb-usb/dvb-usb-firmware.c b/drivers/media/usb/dvb-usb/dvb-usb-firmware.c index ab9866024ec7..04033efe7ad5 100644 --- a/drivers/media/usb/dvb-usb/dvb-usb-firmware.c +++ b/drivers/media/usb/dvb-usb/dvb-usb-firmware.c @@ -36,16 +36,18 @@ static int usb_cypress_writemem(struct usb_device *udev,u16 addr,u8 *data, u8 le int usb_cypress_load_firmware(struct usb_device *udev, const struct firmware *fw, int type) { struct hexline *hx; - u8 reset; - int ret,pos=0; + u8 *buf; + int ret, pos = 0; + u16 cpu_cs_register = cypress[type].cpu_cs_register; - hx = kmalloc(sizeof(*hx), GFP_KERNEL); - if (!hx) + buf = kmalloc(sizeof(*hx), GFP_KERNEL); + if (!buf) return -ENOMEM; + hx = (struct hexline *)buf; /* stop the CPU */ - reset = 1; - if ((ret = usb_cypress_writemem(udev,cypress[type].cpu_cs_register,&reset,1)) != 1) + buf[0] = 1; + if (usb_cypress_writemem(udev, cpu_cs_register, buf, 1) != 1) err("could not stop the USB controller CPU."); while ((ret = dvb_usb_get_hexline(fw, hx, &pos)) > 0) { @@ -61,21 +63,21 @@ int usb_cypress_load_firmware(struct usb_device *udev, const struct firmware *fw } if (ret < 0) { err("firmware download failed at %d with %d",pos,ret); - kfree(hx); + kfree(buf); return ret; } if (ret == 0) { /* restart the CPU */ - reset = 0; - if (ret || usb_cypress_writemem(udev,cypress[type].cpu_cs_register,&reset,1) != 1) { + buf[0] = 0; + if (usb_cypress_writemem(udev, cpu_cs_register, buf, 1) != 1) { err("could not restart the USB controller CPU."); ret = -EINVAL; } } else ret = -EIO; - kfree(hx); + kfree(buf); return ret; }