[PATCH] [media] lmedm04: Do not unlock mutex if mutex_lock_interruptible failed

From: Alexey Khoroshilov
Date: Fri Apr 15 2011 - 17:05:56 EST


There are a couple of places where mutex_unlock() is called even
if mutex_lock_interruptible() failed. The patch fixes the issue.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@xxxxxxxxx>
---
drivers/media/dvb/dvb-usb/lmedm04.c | 12 +++++++-----
1 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/media/dvb/dvb-usb/lmedm04.c b/drivers/media/dvb/dvb-usb/lmedm04.c
index f2db012..40907df 100644
--- a/drivers/media/dvb/dvb-usb/lmedm04.c
+++ b/drivers/media/dvb/dvb-usb/lmedm04.c
@@ -591,9 +591,10 @@ static int lme2510_streaming_ctrl(struct dvb_usb_adapter *adap, int onoff)
else {
deb_info(1, "STM Steam Off");
/* mutex is here only to avoid collision with I2C */
- ret = mutex_lock_interruptible(&adap->dev->i2c_mutex);
+ if (mutex_lock_interruptible(&adap->dev->i2c_mutex) < 0)
+ return -EAGAIN;

- ret |= lme2510_usb_talk(adap->dev, clear_reg_3,
+ ret = lme2510_usb_talk(adap->dev, clear_reg_3,
sizeof(clear_reg_3), rbuf, rlen);
st->stream_on = 0;
st->i2c_talk_onoff = 1;
@@ -1017,12 +1018,13 @@ static int lme2510_powerup(struct dvb_usb_device *d, int onoff)
static u8 rbuf[1];
int ret, len = 3, rlen = 1;

- ret = mutex_lock_interruptible(&d->i2c_mutex);
+ if (mutex_lock_interruptible(&d->i2c_mutex) < 0)
+ return -EAGAIN;

if (onoff)
- ret |= lme2510_usb_talk(d, lnb_on, len, rbuf, rlen);
+ ret = lme2510_usb_talk(d, lnb_on, len, rbuf, rlen);
else
- ret |= lme2510_usb_talk(d, lnb_off, len, rbuf, rlen);
+ ret = lme2510_usb_talk(d, lnb_off, len, rbuf, rlen);

st->i2c_talk_onoff = 1;

--
1.7.1

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