From 3d46d7108dd3ff8b1d477bc2b7b061b12690e83c Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Thu, 28 Dec 2017 17:22:51 -0500
Subject: [PATCH] usx2y: don't bother with memdup_user() for 16-byte structure
Git-commit: 3d46d7108dd3ff8b1d477bc2b7b061b12690e83c
Patch-mainline: v4.16-rc1
References: bsc#1121278
... when it can bloody well go into a local variable.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
sound/usb/usx2y/us122l.c | 43 +++++++++++++++++-----------------------
1 file changed, 18 insertions(+), 25 deletions(-)
diff --git a/sound/usb/usx2y/us122l.c b/sound/usb/usx2y/us122l.c
index 159da1f3924e..8c394178a385 100644
--- a/sound/usb/usx2y/us122l.c
+++ b/sound/usb/usx2y/us122l.c
@@ -378,7 +378,7 @@ static bool us122l_start(struct us122l *us122l,
static int usb_stream_hwdep_ioctl(struct snd_hwdep *hw, struct file *file,
unsigned cmd, unsigned long arg)
{
- struct usb_stream_config *cfg;
+ struct usb_stream_config cfg;
struct us122l *us122l = hw->private_data;
struct usb_stream *s;
unsigned min_period_frames;
@@ -388,24 +388,21 @@ static int usb_stream_hwdep_ioctl(struct snd_hwdep *hw, struct file *file,
if (cmd != SNDRV_USB_STREAM_IOCTL_SET_PARAMS)
return -ENOTTY;
- cfg = memdup_user((void *)arg, sizeof(*cfg));
- if (IS_ERR(cfg))
- return PTR_ERR(cfg);
+ if (copy_from_user(&cfg, (void __user *)arg, sizeof(cfg)))
+ return -EFAULT;
+
+ if (cfg.version != USB_STREAM_INTERFACE_VERSION)
+ return -ENXIO;
- if (cfg->version != USB_STREAM_INTERFACE_VERSION) {
- err = -ENXIO;
- goto free;
- }
high_speed = us122l->dev->speed == USB_SPEED_HIGH;
- if ((cfg->sample_rate != 44100 && cfg->sample_rate != 48000 &&
+ if ((cfg.sample_rate != 44100 && cfg.sample_rate != 48000 &&
(!high_speed ||
- (cfg->sample_rate != 88200 && cfg->sample_rate != 96000))) ||
- cfg->frame_size != 6 ||
- cfg->period_frames > 0x3000) {
- err = -EINVAL;
- goto free;
- }
- switch (cfg->sample_rate) {
+ (cfg.sample_rate != 88200 && cfg.sample_rate != 96000))) ||
+ cfg.frame_size != 6 ||
+ cfg.period_frames > 0x3000)
+ return -EINVAL;
+
+ switch (cfg.sample_rate) {
case 44100:
min_period_frames = 48;
break;
@@ -418,10 +415,8 @@ static int usb_stream_hwdep_ioctl(struct snd_hwdep *hw, struct file *file,
}
if (!high_speed)
min_period_frames <<= 1;
- if (cfg->period_frames < min_period_frames) {
- err = -EINVAL;
- goto free;
- }
+ if (cfg.period_frames < min_period_frames)
+ return -EINVAL;
snd_power_wait(hw->card, SNDRV_CTL_POWER_D0);
@@ -430,24 +425,22 @@ static int usb_stream_hwdep_ioctl(struct snd_hwdep *hw, struct file *file,
if (!us122l->master)
us122l->master = file;
else if (us122l->master != file) {
- if (!s || memcmp(cfg, &s->cfg, sizeof(*cfg))) {
+ if (!s || memcmp(&cfg, &s->cfg, sizeof(cfg))) {
err = -EIO;
goto unlock;
}
us122l->slave = file;
}
- if (!s || memcmp(cfg, &s->cfg, sizeof(*cfg)) ||
+ if (!s || memcmp(&cfg, &s->cfg, sizeof(cfg)) ||
s->state == usb_stream_xrun) {
us122l_stop(us122l);
- if (!us122l_start(us122l, cfg->sample_rate, cfg->period_frames))
+ if (!us122l_start(us122l, cfg.sample_rate, cfg.period_frames))
err = -EIO;
else
err = 1;
}
unlock:
mutex_unlock(&us122l->mutex);
-free:
- kfree(cfg);
wake_up_all(&us122l->sk.sleep);
return err;
}
--
2.20.1