Home Home > GIT Browse
summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorDan Carpenter <dan.carpenter@oracle.com>2013-08-15 15:52:57 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-09-14 05:50:48 -0700
commit7d2754c66e451ac82fd5e93bdb715e59c4bfdb02 (patch)
tree950bed67c268dea41268f34d4319ba1dfba5f0af
parent24e6771d4fce7c77b2569fa33131c871a2c5642e (diff)
tun: signedness bug in tun_get_user()
[ Upstream commit 15718ea0d844e4816dbd95d57a8a0e3e264ba90e ] The recent fix d9bf5f1309 "tun: compare with 0 instead of total_len" is not totally correct. Because "len" and "sizeof()" are size_t type, that means they are never less than zero. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/net/tun.c6
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 28c5c6a31b75..476b2edd267d 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -614,8 +614,9 @@ static __inline__ ssize_t tun_get_user(struct tun_struct *tun,
int offset = 0;
if (!(tun->flags & TUN_NO_PI)) {
- if ((len -= sizeof(pi)) > count)
+ if (len < sizeof(pi))
return -EINVAL;
+ len -= sizeof(pi);
if (memcpy_fromiovecend((void *)&pi, iv, 0, sizeof(pi)))
return -EFAULT;
@@ -623,8 +624,9 @@ static __inline__ ssize_t tun_get_user(struct tun_struct *tun,
}
if (tun->flags & TUN_VNET_HDR) {
- if ((len -= tun->vnet_hdr_sz) > count)
+ if (len < tun->vnet_hdr_sz)
return -EINVAL;
+ len -= tun->vnet_hdr_sz;
if (memcpy_fromiovecend((void *)&gso, iv, offset, sizeof(gso)))
return -EFAULT;