diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2020-03-29 17:18:30 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2020-05-20 20:31:27 -0400 |
| commit | 931ca7ab7fe804d77bc6952f1512950c0d870f26 (patch) | |
| tree | ec55897513da03af5bc76b9f9f7a33ad1d59b4f6 /net/ipv6 | |
| parent | e9c375fb5edeb550786d1436784db909bf672e9f (diff) | |
ip*_mc_gsfget(): lift copyout of struct group_filter into callers
pass the userland pointer to the array in its tail, so that part
gets copied out by our functions; copyout of everything else is
done in the callers. Rationale: reuse for compat; the array
is the same in native and compat, the layout of parts before it
is different for compat.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/ipv6_sockglue.c | 18 | ||||
| -rw-r--r-- | net/ipv6/mcast.c | 10 |
2 files changed, 17 insertions, 11 deletions
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 96e3f603c8d8..e4a62ca1a3d0 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -1056,18 +1056,28 @@ static int do_ipv6_getsockopt(struct sock *sk, int level, int optname, break; case MCAST_MSFILTER: { + struct group_filter __user *p = (void __user *)optval; struct group_filter gsf; + const int size0 = offsetof(struct group_filter, gf_slist); + int num; int err; - if (len < GROUP_FILTER_SIZE(0)) + if (len < size0) return -EINVAL; - if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) + if (copy_from_user(&gsf, p, size0)) return -EFAULT; if (gsf.gf_group.ss_family != AF_INET6) return -EADDRNOTAVAIL; + num = gsf.gf_numsrc; lock_sock(sk); - err = ip6_mc_msfget(sk, &gsf, - (struct group_filter __user *)optval, optlen); + err = ip6_mc_msfget(sk, &gsf, p->gf_slist); + if (!err) { + if (num > gsf.gf_numsrc) + num = gsf.gf_numsrc; + if (put_user(GROUP_FILTER_SIZE(num), optlen) || + copy_to_user(p, &gsf, size0)) + err = -EFAULT; + } release_sock(sk); return err; } diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c index eaa4c2cc2fbb..97d796c7d6c0 100644 --- a/net/ipv6/mcast.c +++ b/net/ipv6/mcast.c @@ -547,7 +547,7 @@ done: } int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf, - struct group_filter __user *optval, int __user *optlen) + struct sockaddr_storage *p) { int err, i, count, copycount; const struct in6_addr *group; @@ -592,14 +592,10 @@ int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf, copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc; gsf->gf_numsrc = count; - if (put_user(GROUP_FILTER_SIZE(copycount), optlen) || - copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) { - return -EFAULT; - } /* changes to psl require the socket lock, and a write lock * on pmc->sflock. We have the socket lock so reading here is safe. */ - for (i = 0; i < copycount; i++) { + for (i = 0; i < copycount; i++, p++) { struct sockaddr_in6 *psin6; struct sockaddr_storage ss; @@ -607,7 +603,7 @@ int ip6_mc_msfget(struct sock *sk, struct group_filter *gsf, memset(&ss, 0, sizeof(ss)); psin6->sin6_family = AF_INET6; psin6->sin6_addr = psl->sl_addr[i]; - if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss))) + if (copy_to_user(p, &ss, sizeof(ss))) return -EFAULT; } return 0; |