Commit 4167a960 authored by Gustavo A. R. Silva's avatar Gustavo A. R. Silva Committed by David S. Miller
Browse files

net/ipv4: Revert use of struct_size() helper 



Revert the use of structr_size() and stay with IP_MSFILTER_SIZE() for
now, as in this case, the size of struct ip_msfilter didn't change with
the addition of the flexible array imsf_slist_flex[]. So, if we use
struct_size() we will be allocating and calculating the size of
struct ip_msfilter with one too many items for imsf_slist_flex[].

We might use struct_size() in the future, but for now let's stay
with IP_MSFILTER_SIZE().

Fixes: 	2d3e5caf ("net/ipv4: Replace one-element array with flexible-array member")
Signed-off-by: default avatarGustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent af352460

net/ipv4/igmp.c

+2 −2
Original line number Diff line number Diff line
@@ -2553,8 +2553,8 @@ int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf, 
	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;

	len = flex_array_size(psl, sl_addr, copycount);

	msf->imsf_numsrc = count;

	if (put_user(struct_size(optval, imsf_slist_flex, copycount), optlen) ||

	    copy_to_user(optval, msf, struct_size(optval, imsf_slist_flex, 0))) {

	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||

	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {

		return -EFAULT;

	}

	if (len &&

net/ipv4/ip_sockglue.c

+5 −7
Original line number Diff line number Diff line
@@ -667,7 +667,7 @@ static int set_mcast_msfilter(struct sock *sk, int ifindex, 
	struct sockaddr_in *psin;

	int err, i;



	msf = kmalloc(struct_size(msf, imsf_slist_flex, numsrc), GFP_KERNEL);

	msf = kmalloc(IP_MSFILTER_SIZE(numsrc), GFP_KERNEL);

	if (!msf)

		return -ENOBUFS;
@@ -1228,7 +1228,7 @@ static int do_ip_setsockopt(struct sock *sk, int level, int optname, 
	{

		struct ip_msfilter *msf;



		if (optlen < struct_size(msf, imsf_slist_flex, 0))

		if (optlen < IP_MSFILTER_SIZE(0))

			goto e_inval;

		if (optlen > sysctl_optmem_max) {

			err = -ENOBUFS;
@@ -1246,8 +1246,7 @@ static int do_ip_setsockopt(struct sock *sk, int level, int optname, 
			err = -ENOBUFS;

			break;

		}

		if (struct_size(msf, imsf_slist_flex, msf->imsf_numsrc) >

		    optlen) {

		if (IP_MSFILTER_SIZE(msf->imsf_numsrc) > optlen) {

			kfree(msf);

			err = -EINVAL;

			break;
@@ -1660,12 +1659,11 @@ static int do_ip_getsockopt(struct sock *sk, int level, int optname, 
	{

		struct ip_msfilter msf;



		if (len < struct_size(&msf, imsf_slist_flex, 0)) {

		if (len < IP_MSFILTER_SIZE(0)) {

			err = -EINVAL;

			goto out;

		}

		if (copy_from_user(&msf, optval,

				   struct_size(&msf, imsf_slist_flex, 0))) {

		if (copy_from_user(&msf, optval, IP_MSFILTER_SIZE(0))) {

			err = -EFAULT;

			goto out;

		}