sound: line6: move to use usb_control_msg_send() and usb_control_msg_recv()

The usb_control_msg_send() and usb_control_msg_recv() calls can return
an error if a "short" write/read happens, and they can handle data off
of the stack, so move the driver over to using those calls instead,
saving some logic when dynamically allocating memory.

Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Vasily Khoruzhick <anarsoul@gmail.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20200914153756.3412156-9-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/sound/usb/line6/driver.c b/sound/usb/line6/driver.c
index 60674ce4879b17c41e4f1ba0e6d7db0b3b6d597c..601292c514913154e2e861373dac253d892654f5 100644 (file)
--- a/sound/usb/line6/driver.c
+++ b/sound/usb/line6/driver.c
@@ -337,23 +337,18 @@ int line6_read_data(struct usb_line6 *line6, unsigned address, void *data,
 {
        struct usb_device *usbdev = line6->usbdev;
        int ret;
-       unsigned char *len;
+       u8 len;
        unsigned count;
 
        if (address > 0xffff || datalen > 0xff)
                return -EINVAL;
 
-       len = kmalloc(1, GFP_KERNEL);
-       if (!len)
-               return -ENOMEM;
-
        /* query the serial number: */
-       ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x67,
-                             USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
-                             (datalen << 8) | 0x21, address,
-                             NULL, 0, LINE6_TIMEOUT * HZ);
-
-       if (ret < 0) {
+       ret = usb_control_msg_send(usbdev, 0, 0x67,
+                                  USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
+                                  (datalen << 8) | 0x21, address, NULL, 0,
+                                  LINE6_TIMEOUT * HZ);
+       if (ret) {
                dev_err(line6->ifcdev, "read request failed (error %d)\n", ret);
                goto exit;
        }
@@ -362,45 +357,41 @@ int line6_read_data(struct usb_line6 *line6, unsigned address, void *data,
        for (count = 0; count < LINE6_READ_WRITE_MAX_RETRIES; count++) {
                mdelay(LINE6_READ_WRITE_STATUS_DELAY);
 
-               ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0), 0x67,
-                                     USB_TYPE_VENDOR | USB_RECIP_DEVICE |
-                                     USB_DIR_IN,
-                                     0x0012, 0x0000, len, 1,
-                                     LINE6_TIMEOUT * HZ);
-               if (ret < 0) {
+               ret = usb_control_msg_recv(usbdev, 0, 0x67,
+                                          USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
+                                          0x0012, 0x0000, &len, 1,
+                                          LINE6_TIMEOUT * HZ);
+               if (ret) {
                        dev_err(line6->ifcdev,
                                "receive length failed (error %d)\n", ret);
                        goto exit;
                }
 
-               if (*len != 0xff)
+               if (len != 0xff)
                        break;
        }
 
        ret = -EIO;
-       if (*len == 0xff) {
+       if (len == 0xff) {
                dev_err(line6->ifcdev, "read failed after %d retries\n",
                        count);
                goto exit;
-       } else if (*len != datalen) {
+       } else if (len != datalen) {
                /* should be equal or something went wrong */
                dev_err(line6->ifcdev,
                        "length mismatch (expected %d, got %d)\n",
-                       (int)datalen, (int)*len);
+                       (int)datalen, len);
                goto exit;
        }
 
        /* receive the result: */
-       ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0), 0x67,
-                             USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
-                             0x0013, 0x0000, data, datalen,
-                             LINE6_TIMEOUT * HZ);
-
-       if (ret < 0)
+       ret = usb_control_msg_recv(usbdev, 0, 0x67,
+                                  USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
+                                  0x0013, 0x0000, data, datalen, LINE6_TIMEOUT * HZ);
+       if (ret)
                dev_err(line6->ifcdev, "read failed (error %d)\n", ret);
 
 exit:
-       kfree(len);
        return ret;
 }
 EXPORT_SYMBOL_GPL(line6_read_data);
@@ -423,12 +414,10 @@ int line6_write_data(struct usb_line6 *line6, unsigned address, void *data,
        if (!status)
                return -ENOMEM;
 
-       ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x67,
-                             USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
-                             0x0022, address, data, datalen,
-                             LINE6_TIMEOUT * HZ);
-
-       if (ret < 0) {
+       ret = usb_control_msg_send(usbdev, 0, 0x67,
+                                  USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
+                                  0x0022, address, data, datalen, LINE6_TIMEOUT * HZ);
+       if (ret) {
                dev_err(line6->ifcdev,
                        "write request failed (error %d)\n", ret);
                goto exit;
@@ -437,14 +426,10 @@ int line6_write_data(struct usb_line6 *line6, unsigned address, void *data,
        for (count = 0; count < LINE6_READ_WRITE_MAX_RETRIES; count++) {
                mdelay(LINE6_READ_WRITE_STATUS_DELAY);
 
-               ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0),
-                                     0x67,
-                                     USB_TYPE_VENDOR | USB_RECIP_DEVICE |
-                                     USB_DIR_IN,
-                                     0x0012, 0x0000,
-                                     status, 1, LINE6_TIMEOUT * HZ);
-
-               if (ret < 0) {
+               ret = usb_control_msg_recv(usbdev, 0, 0x67,
+                                          USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
+                                          0x0012, 0x0000, status, 1, LINE6_TIMEOUT * HZ);
+               if (ret) {
                        dev_err(line6->ifcdev,
                                "receiving status failed (error %d)\n", ret);
                        goto exit;

diff --git a/sound/usb/line6/podhd.c b/sound/usb/line6/podhd.c
index eef45f7fef0db04a107de2744f49f12b99ca8aa5..a1261f55d62b4f4a1d9792b4f85778394c7b9667 100644 (file)
--- a/sound/usb/line6/podhd.c
+++ b/sound/usb/line6/podhd.c
@@ -183,29 +183,25 @@ static const struct attribute_group podhd_dev_attr_group = {
 static int podhd_dev_start(struct usb_line6_podhd *pod)
 {
        int ret;
-       u8 *init_bytes;
+       u8 init_bytes[8];
        int i;
        struct usb_device *usbdev = pod->line6.usbdev;
 
-       init_bytes = kmalloc(8, GFP_KERNEL);
-       if (!init_bytes)
-               return -ENOMEM;
-
-       ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0),
+       ret = usb_control_msg_send(usbdev, 0,
                                        0x67, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
                                        0x11, 0,
                                        NULL, 0, LINE6_TIMEOUT * HZ);
-       if (ret < 0) {
+       if (ret) {
                dev_err(pod->line6.ifcdev, "read request failed (error %d)\n", ret);
                goto exit;
        }
 
        /* NOTE: looks like some kind of ping message */
-       ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0), 0x67,
+       ret = usb_control_msg_recv(usbdev, 0, 0x67,
                                        USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
                                        0x11, 0x0,
                                        init_bytes, 3, LINE6_TIMEOUT * HZ);
-       if (ret < 0) {
+       if (ret) {
                dev_err(pod->line6.ifcdev,
                        "receive length failed (error %d)\n", ret);
                goto exit;
@@ -220,13 +216,12 @@ static int podhd_dev_start(struct usb_line6_podhd *pod)
                        goto exit;
        }
 
-       ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0),
+       ret = usb_control_msg_send(usbdev, 0,
                                        USB_REQ_SET_FEATURE,
                                        USB_TYPE_STANDARD | USB_RECIP_DEVICE | USB_DIR_OUT,
                                        1, 0,
                                        NULL, 0, LINE6_TIMEOUT * HZ);
 exit:
-       kfree(init_bytes);
        return ret;
 }
 

diff --git a/sound/usb/line6/toneport.c b/sound/usb/line6/toneport.c
index 94dd5e7ab2e682d5babae66fa9cb47e50ad8dd81..a9b56085b76a66785dd867b72bc508558f0e4cae 100644 (file)
--- a/sound/usb/line6/toneport.c
+++ b/sound/usb/line6/toneport.c
@@ -126,11 +126,11 @@ static int toneport_send_cmd(struct usb_device *usbdev, int cmd1, int cmd2)
 {
        int ret;
 
-       ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x67,
-                             USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
-                             cmd1, cmd2, NULL, 0, LINE6_TIMEOUT * HZ);
+       ret = usb_control_msg_send(usbdev, 0, 0x67,
+                                  USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
+                                  cmd1, cmd2, NULL, 0, LINE6_TIMEOUT * HZ);
 
-       if (ret < 0) {
+       if (ret) {
                dev_err(&usbdev->dev, "send failed (error %d)\n", ret);
                return ret;
        }