diff options
| author | Dan Carpenter <dan.carpenter@oracle.com> | 2019-05-22 11:45:13 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-05-22 17:22:14 -0700 |
| commit | ccfb62f27beb295103e9392462b20a6ed807d0ea (patch) | |
| tree | c00adc85e6999f71e4042645ce08d1af495f4f83 /drivers/isdn | |
| parent | c1e85c6ce57ef1eb73966152993a341c8123a8ea (diff) | |
| download | lwn-ccfb62f27beb295103e9392462b20a6ed807d0ea.tar.gz lwn-ccfb62f27beb295103e9392462b20a6ed807d0ea.zip | |
mISDN: make sure device name is NUL terminated
The user can change the device_name with the IMSETDEVNAME ioctl, but we
need to ensure that the user's name is NUL terminated. Otherwise it
could result in a buffer overflow when we copy the name back to the user
with IMGETDEVINFO ioctl.
I also changed two strcpy() calls which handle the name to strscpy().
Hopefully, there aren't any other ways to create a too long name, but
it's nice to do this as a kernel hardening measure.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/isdn')
| -rw-r--r-- | drivers/isdn/mISDN/socket.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/isdn/mISDN/socket.c b/drivers/isdn/mISDN/socket.c index a14e35d40538..84e1d4c2db66 100644 --- a/drivers/isdn/mISDN/socket.c +++ b/drivers/isdn/mISDN/socket.c @@ -393,7 +393,7 @@ data_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) memcpy(di.channelmap, dev->channelmap, sizeof(di.channelmap)); di.nrbchan = dev->nrbchan; - strcpy(di.name, dev_name(&dev->dev)); + strscpy(di.name, dev_name(&dev->dev), sizeof(di.name)); if (copy_to_user((void __user *)arg, &di, sizeof(di))) err = -EFAULT; } else @@ -676,7 +676,7 @@ base_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) memcpy(di.channelmap, dev->channelmap, sizeof(di.channelmap)); di.nrbchan = dev->nrbchan; - strcpy(di.name, dev_name(&dev->dev)); + strscpy(di.name, dev_name(&dev->dev), sizeof(di.name)); if (copy_to_user((void __user *)arg, &di, sizeof(di))) err = -EFAULT; } else @@ -690,6 +690,7 @@ base_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) err = -EFAULT; break; } + dn.name[sizeof(dn.name) - 1] = '\0'; dev = get_mdevice(dn.id); if (dev) err = device_rename(&dev->dev, dn.name); |