Commit 726bc6b0 authored Feb 27, 2013 by Guenter Roeck Committed by David S. Miller Feb 27, 2013

net/sctp: Validate parameter size for SCTP_GET_ASSOC_STATS



Building sctp may fail with:

In function ‘copy_from_user’,
    inlined from ‘sctp_getsockopt_assoc_stats’ at
    net/sctp/socket.c:5656:20:
arch/x86/include/asm/uaccess_32.h:211:26: error: call to
    ‘copy_from_user_overflow’ declared with attribute error: copy_from_user()
    buffer size is not provably correct

if built with W=1 due to a missing parameter size validation
before the call to copy_from_user.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 45af3fb4

net/sctp/socket.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -5653,6 +5653,9 @@ static int sctp_getsockopt_assoc_stats(struct sock *sk, int len,
		if (len < sizeof(sctp_assoc_t))
		return -EINVAL;

		/* Allow the struct to grow and fill in as much as possible */
		len = min_t(size_t, len, sizeof(sas));

		if (copy_from_user(&sas, optval, len))
		return -EFAULT;

		@@ -5686,9 +5689,6 @@ static int sctp_getsockopt_assoc_stats(struct sock *sk, int len,
		/* Mark beginning of a new observation period */
		asoc->stats.max_obs_rto = asoc->rto_min;

		/* Allow the struct to grow and fill in as much as possible */
		len = min_t(size_t, len, sizeof(sas));

		if (put_user(len, optlen))
		return -EFAULT;