[ Upstream commit 156e0b1a8112b76e351684ac948c59757037ac36 ] The dev_info.name[] array has space for RIO_MAX_DEVNAME_SZ + 1 characters. But the problem here is that we don't ensure that the user put a NUL terminator on the end of the string. It could lead to an out of bounds read.
Link: http://lkml.kernel.org/r/20190529110601.GB19119@mwanda Fixes: e8de370188d0 ("rapidio: add mport char device driver") Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com> Acked-by: Alexandre Bounine <alex.b...@gmail.com> Cc: Ira Weiny <ira.we...@intel.com> Signed-off-by: Andrew Morton <a...@linux-foundation.org> Signed-off-by: Linus Torvalds <torva...@linux-foundation.org> Signed-off-by: Sasha Levin <sas...@kernel.org> --- drivers/rapidio/devices/rio_mport_cdev.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/rapidio/devices/rio_mport_cdev.c b/drivers/rapidio/devices/rio_mport_cdev.c index 76afe1449cab1..ecd71efe8ea00 100644 --- a/drivers/rapidio/devices/rio_mport_cdev.c +++ b/drivers/rapidio/devices/rio_mport_cdev.c @@ -1742,6 +1742,7 @@ static int rio_mport_add_riodev(struct mport_cdev_priv *priv, if (copy_from_user(&dev_info, arg, sizeof(dev_info))) return -EFAULT; + dev_info.name[sizeof(dev_info.name) - 1] = '\0'; rmcd_debug(RDEV, "name:%s ct:0x%x did:0x%x hc:0x%x", dev_info.name, dev_info.comptag, dev_info.destid, dev_info.hopcount); @@ -1873,6 +1874,7 @@ static int rio_mport_del_riodev(struct mport_cdev_priv *priv, void __user *arg) if (copy_from_user(&dev_info, arg, sizeof(dev_info))) return -EFAULT; + dev_info.name[sizeof(dev_info.name) - 1] = '\0'; mport = priv->md->mport; -- 2.20.1
