diff --git a/drivers/net/tun.c b/drivers/net/tun.c index ea6ada39db1..7bbc43fbb72 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1087,9 +1087,11 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, } if (tun->flags & TUN_VNET_HDR) { - if (len < tun->vnet_hdr_sz) + int vnet_hdr_sz = ACCESS_ONCE(tun->vnet_hdr_sz); + + if (len < vnet_hdr_sz) return -EINVAL; - len -= tun->vnet_hdr_sz; + len -= vnet_hdr_sz; if (memcpy_fromiovecend((void *)&gso, iv, offset, sizeof(gso))) return -EFAULT; @@ -1100,7 +1102,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, if (gso.hdr_len > len) return -EINVAL; - offset += tun->vnet_hdr_sz; + offset += vnet_hdr_sz; } if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) { @@ -1275,7 +1277,7 @@ static ssize_t tun_put_user(struct tun_struct *tun, int vnet_hdr_sz = 0; if (tun->flags & TUN_VNET_HDR) - vnet_hdr_sz = tun->vnet_hdr_sz; + vnet_hdr_sz = ACCESS_ONCE(tun->vnet_hdr_sz); if (!(tun->flags & TUN_NO_PI)) { if ((len -= sizeof(pi)) < 0)