From: Mathias Krause <minipli@googlemail.com>
To: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org, Mathias Krause <minipli@googlemail.com>
Subject: [PATCH] net/tun: fix ioctl() based info leaks
Date: Sun, 29 Jul 2012 22:58:14 +0200 [thread overview]
Message-ID: <1343595494-10414-1-git-send-email-minipli@googlemail.com> (raw)
The tun module leaks up to 36 bytes of memory by not 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>
---
drivers/net/tun.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index 987aeef..cadeb94 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -1252,9 +1252,12 @@ 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?".
--
1.7.10.4
next reply other threads:[~2012-07-29 20:58 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-29 20:58 Mathias Krause [this message]
2012-07-29 23:11 ` [PATCH] net/tun: fix ioctl() based info leaks richard -rw- weinberger
2012-07-30 5:38 ` Mathias Krause
2012-07-30 5:45 ` [PATCH v2] " Mathias Krause
2012-07-30 6:20 ` David Miller
2012-07-30 6:22 ` Eric Dumazet
2012-07-30 6:34 ` David Miller
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