Commit 0dfe6581 authored by Al Viro's avatar Al Viro
Browse files

get rid of compat_mc_getsockopt() 



now we can do MCAST_MSFILTER in compat ->getsockopt() without
playing silly buggers with copying things back and forth.
We can form a native struct group_filter (sans the variable-length
tail) on stack, pass that + pointer to the tail of original request
to the helper doing the bulk of the work, then do the rest of
copyout - same as the native getsockopt() does.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 931ca7ab

include/net/compat.h

+0 −3
Original line number Diff line number Diff line
@@ -70,9 +70,6 @@ int cmsghdr_from_user_compat_to_kern(struct msghdr *, struct sock *, 
int compat_mc_setsockopt(struct sock *, int, int, char __user *, unsigned int,

			 int (*)(struct sock *, int, int, char __user *,

				 unsigned int));

int compat_mc_getsockopt(struct sock *, int, int, char __user *, int __user *,

			 int (*)(struct sock *, int, int, char __user *,

				 int __user *));



struct compat_group_req {

	__u32				 gr_interface;

net/compat.c

+0 −79
Original line number Diff line number Diff line
@@ -538,85 +538,6 @@ int compat_mc_setsockopt(struct sock *sock, int level, int optname, 
}

EXPORT_SYMBOL(compat_mc_setsockopt);



int compat_mc_getsockopt(struct sock *sock, int level, int optname,

	char __user *optval, int __user *optlen,

	int (*getsockopt)(struct sock *, int, int, char __user *, int __user *))

{

	struct compat_group_filter __user *gf32 = (void __user *)optval;

	struct group_filter __user *kgf;

	int __user	*koptlen;

	u32 interface, fmode, numsrc;

	int klen, ulen, err;



	if (optname != MCAST_MSFILTER)

		return getsockopt(sock, level, optname, optval, optlen);



	koptlen = compat_alloc_user_space(sizeof(*koptlen));

	if (!access_ok(optlen, sizeof(*optlen)) ||

	    __get_user(ulen, optlen))

		return -EFAULT;



	/* adjust len for pad */

	klen = ulen + sizeof(*kgf) - sizeof(*gf32);



	if (klen < GROUP_FILTER_SIZE(0))

		return -EINVAL;



	if (!access_ok(koptlen, sizeof(*koptlen)) ||

	    __put_user(klen, koptlen))

		return -EFAULT;



	/* have to allow space for previous compat_alloc_user_space, too */

	kgf = compat_alloc_user_space(klen+sizeof(*optlen));



	if (!access_ok(gf32, __COMPAT_GF0_SIZE) ||

	    __get_user(interface, &gf32->gf_interface) ||

	    __get_user(fmode, &gf32->gf_fmode) ||

	    __get_user(numsrc, &gf32->gf_numsrc) ||

	    __put_user(interface, &kgf->gf_interface) ||

	    __put_user(fmode, &kgf->gf_fmode) ||

	    __put_user(numsrc, &kgf->gf_numsrc) ||

	    copy_in_user(&kgf->gf_group, &gf32->gf_group, sizeof(kgf->gf_group)))

		return -EFAULT;



	err = getsockopt(sock, level, optname, (char __user *)kgf, koptlen);

	if (err)

		return err;



	if (!access_ok(koptlen, sizeof(*koptlen)) ||

	    __get_user(klen, koptlen))

		return -EFAULT;



	ulen = klen - (sizeof(*kgf)-sizeof(*gf32));



	if (!access_ok(optlen, sizeof(*optlen)) ||

	    __put_user(ulen, optlen))

		return -EFAULT;



	if (!access_ok(kgf, klen) ||

	    !access_ok(gf32, ulen) ||

	    __get_user(interface, &kgf->gf_interface) ||

	    __get_user(fmode, &kgf->gf_fmode) ||

	    __get_user(numsrc, &kgf->gf_numsrc) ||

	    __put_user(interface, &gf32->gf_interface) ||

	    __put_user(fmode, &gf32->gf_fmode) ||

	    __put_user(numsrc, &gf32->gf_numsrc))

		return -EFAULT;

	if (numsrc) {

		int copylen;



		klen -= GROUP_FILTER_SIZE(0);

		copylen = numsrc * sizeof(gf32->gf_slist[0]);

		if (copylen > klen)

			copylen = klen;

		if (copy_in_user(gf32->gf_slist, kgf->gf_slist, copylen))

			return -EFAULT;

	}

	return err;

}

EXPORT_SYMBOL(compat_mc_getsockopt);





/* Argument list sizes for compat_sys_socketcall */

#define AL(x) ((x) * sizeof(u32))

static unsigned char nas[21] = {

net/ipv4/ip_sockglue.c

+41 −3
Original line number Diff line number Diff line
@@ -1607,9 +1607,47 @@ int compat_ip_getsockopt(struct sock *sk, int level, int optname, 
{

	int err;



	if (optname == MCAST_MSFILTER)

		return compat_mc_getsockopt(sk, level, optname, optval, optlen,

			ip_getsockopt);

	if (optname == MCAST_MSFILTER) {

		const int size0 = offsetof(struct compat_group_filter, gf_slist);

		struct compat_group_filter __user *p = (void __user *)optval;

		struct compat_group_filter gf32;

		struct group_filter gf;

		int ulen, err;

		int num;



		if (level != SOL_IP)

			return -EOPNOTSUPP;



		if (get_user(ulen, optlen))

			return -EFAULT;



		if (ulen < size0)

			return -EINVAL;



		if (copy_from_user(&gf32, p, size0))

			return -EFAULT;



		gf.gf_interface = gf32.gf_interface;

		gf.gf_fmode = gf32.gf_fmode;

		num = gf.gf_numsrc = gf32.gf_numsrc;

		gf.gf_group = gf32.gf_group;



		rtnl_lock();

		lock_sock(sk);

		err = ip_mc_gsfget(sk, &gf, p->gf_slist);

		release_sock(sk);

		rtnl_unlock();

		if (err)

			return err;

		if (gf.gf_numsrc < num)

			num = gf.gf_numsrc;

		ulen = GROUP_FILTER_SIZE(num) - (sizeof(gf) - sizeof(gf32));

		if (put_user(ulen, optlen) ||

		    put_user(gf.gf_fmode, &p->gf_fmode) ||

		    put_user(gf.gf_numsrc, &p->gf_numsrc))

			return -EFAULT;

		return 0;

	}



	err = do_ip_getsockopt(sk, level, optname, optval, optlen,

		MSG_CMSG_COMPAT);

net/ipv6/ipv6_sockglue.c

+38 −3
Original line number Diff line number Diff line
@@ -1446,9 +1446,44 @@ int compat_ipv6_getsockopt(struct sock *sk, int level, int optname, 
	if (level != SOL_IPV6)

		return -ENOPROTOOPT;



	if (optname == MCAST_MSFILTER)

		return compat_mc_getsockopt(sk, level, optname, optval, optlen,

			ipv6_getsockopt);

	if (optname == MCAST_MSFILTER) {

		const int size0 = offsetof(struct compat_group_filter, gf_slist);

		struct compat_group_filter __user *p = (void __user *)optval;

		struct compat_group_filter gf32;

		struct group_filter gf;

		int ulen, err;

		int num;



		if (get_user(ulen, optlen))

			return -EFAULT;



		if (ulen < size0)

			return -EINVAL;



		if (copy_from_user(&gf32, p, size0))

			return -EFAULT;



		gf.gf_interface = gf32.gf_interface;

		gf.gf_fmode = gf32.gf_fmode;

		num = gf.gf_numsrc = gf32.gf_numsrc;

		gf.gf_group = gf32.gf_group;



		if (gf.gf_group.ss_family != AF_INET6)

			return -EADDRNOTAVAIL;

		lock_sock(sk);

		err = ip6_mc_msfget(sk, &gf, p->gf_slist);

		release_sock(sk);

		if (err)

			return err;

		if (num > gf.gf_numsrc)

			num = gf.gf_numsrc;

		ulen = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32));

		if (put_user(ulen, optlen) ||

		    put_user(gf.gf_fmode, &p->gf_fmode) ||

		    put_user(gf.gf_numsrc, &p->gf_numsrc))

			return -EFAULT;

		return 0;

	}



	err = do_ipv6_getsockopt(sk, level, optname, optval, optlen,

				 MSG_CMSG_COMPAT);

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