Commit a117dacd authored Jul 29, 2012 by Mathias Krause Committed by David S. Miller Jul 29, 2012

net/tun: fix ioctl() based info leaks



The tun module leaks up to 36 bytes of memory by not fully initializing
a structure located on the stack that gets copied to user memory by the
TUNGETIFF and SIOCGIFHWADDR ioctl()s.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent cac83e53

drivers/net/tun.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -1379,9 +1379,11 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
		int vnet_hdr_sz;
		int ret;

		if (cmd == TUNSETIFF \|\| _IOC_TYPE(cmd) == 0x89)
		if (cmd == TUNSETIFF \|\| _IOC_TYPE(cmd) == 0x89) {
		if (copy_from_user(&ifr, argp, ifreq_len))
		return -EFAULT;
		} else
		memset(&ifr, 0, sizeof(ifr));

		if (cmd == TUNGETFEATURES) {
		/* Currently this just means: "what IFF flags are valid?".