From 3ea79249e81e5ed051f2e6480cbde896d99046e8 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Fri, 18 Sep 2015 13:41:09 +0300 Subject: [PATCH] macvtap: fix TUNSETSNDBUF values > 64k Upon TUNSETSNDBUF, macvtap reads the requested sndbuf size into a local variable u. commit 39ec7de7092b ("macvtap: fix uninitialized access on TUNSETIFF") changed its type to u16 (which is the right thing to do for all other macvtap ioctls), breaking all values > 64k. The value of TUNSETSNDBUF is actually a signed 32 bit integer, so the right thing to do is to read it into an int. Cc: David S. Miller Fixes: 39ec7de7092b ("macvtap: fix uninitialized access on TUNSETIFF") Reported-by: Mark A. Peloquin Bisected-by: Matthew Rosato Reported-by: Christian Borntraeger Signed-off-by: Michael S. Tsirkin Tested-by: Matthew Rosato Acked-by: Christian Borntraeger Signed-off-by: David S. Miller --- drivers/net/macvtap.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index edd77342773a..248478c6f6e4 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -1111,10 +1111,10 @@ static long macvtap_ioctl(struct file *file, unsigned int cmd, return 0; case TUNSETSNDBUF: - if (get_user(u, up)) + if (get_user(s, sp)) return -EFAULT; - q->sk.sk_sndbuf = u; + q->sk.sk_sndbuf = s; return 0; case TUNGETVNETHDRSZ: -- 2.20.1