media: lirc: do not pass ERR_PTR to kfree

If memdup_user() fails, txbuf will be an error pointer and passed
to kfree.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Sean Young 2017-12-13 16:09:21 -05:00 committed by Mauro Carvalho Chehab
parent b996157dd2
commit a74b2bff59

View file

@ -231,7 +231,7 @@ static ssize_t ir_lirc_transmit_ir(struct file *file, const char __user *buf,
{
struct lirc_fh *fh = file->private_data;
struct rc_dev *dev = fh->rc;
unsigned int *txbuf = NULL;
unsigned int *txbuf;
struct ir_raw_event *raw = NULL;
ssize_t ret;
size_t count;
@ -246,14 +246,14 @@ static ssize_t ir_lirc_transmit_ir(struct file *file, const char __user *buf,
if (!dev->registered) {
ret = -ENODEV;
goto out;
goto out_unlock;
}
start = ktime_get();
if (!dev->tx_ir) {
ret = -EINVAL;
goto out;
goto out_unlock;
}
if (fh->send_mode == LIRC_MODE_SCANCODE) {
@ -261,17 +261,17 @@ static ssize_t ir_lirc_transmit_ir(struct file *file, const char __user *buf,
if (n != sizeof(scan)) {
ret = -EINVAL;
goto out;
goto out_unlock;
}
if (copy_from_user(&scan, buf, sizeof(scan))) {
ret = -EFAULT;
goto out;
goto out_unlock;
}
if (scan.flags || scan.keycode || scan.timestamp) {
ret = -EINVAL;
goto out;
goto out_unlock;
}
/*
@ -283,26 +283,26 @@ static ssize_t ir_lirc_transmit_ir(struct file *file, const char __user *buf,
if (scan.scancode > U32_MAX ||
!rc_validate_scancode(scan.rc_proto, scan.scancode)) {
ret = -EINVAL;
goto out;
goto out_unlock;
}
raw = kmalloc_array(LIRCBUF_SIZE, sizeof(*raw), GFP_KERNEL);
if (!raw) {
ret = -ENOMEM;
goto out;
goto out_unlock;
}
ret = ir_raw_encode_scancode(scan.rc_proto, scan.scancode,
raw, LIRCBUF_SIZE);
if (ret < 0)
goto out;
goto out_kfree;
count = ret;
txbuf = kmalloc_array(count, sizeof(unsigned int), GFP_KERNEL);
if (!txbuf) {
ret = -ENOMEM;
goto out;
goto out_kfree;
}
for (i = 0; i < count; i++)
@ -318,26 +318,26 @@ static ssize_t ir_lirc_transmit_ir(struct file *file, const char __user *buf,
} else {
if (n < sizeof(unsigned int) || n % sizeof(unsigned int)) {
ret = -EINVAL;
goto out;
goto out_unlock;
}
count = n / sizeof(unsigned int);
if (count > LIRCBUF_SIZE || count % 2 == 0) {
ret = -EINVAL;
goto out;
goto out_unlock;
}
txbuf = memdup_user(buf, n);
if (IS_ERR(txbuf)) {
ret = PTR_ERR(txbuf);
goto out;
goto out_unlock;
}
}
for (i = 0; i < count; i++) {
if (txbuf[i] > IR_MAX_DURATION / 1000 - duration || !txbuf[i]) {
ret = -EINVAL;
goto out;
goto out_kfree;
}
duration += txbuf[i];
@ -345,7 +345,7 @@ static ssize_t ir_lirc_transmit_ir(struct file *file, const char __user *buf,
ret = dev->tx_ir(dev, txbuf, count);
if (ret < 0)
goto out;
goto out_kfree;
if (fh->send_mode == LIRC_MODE_SCANCODE) {
ret = n;
@ -368,10 +368,11 @@ static ssize_t ir_lirc_transmit_ir(struct file *file, const char __user *buf,
schedule_timeout(usecs_to_jiffies(towait));
}
out:
mutex_unlock(&dev->lock);
out_kfree:
kfree(txbuf);
kfree(raw);
out_unlock:
mutex_unlock(&dev->lock);
return ret;
}