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/ipv4 | |
| parent | e9c375fb5edeb550786d1436784db909bf672e9f (diff) | |
| download | linux-931ca7ab7fe804d77bc6952f1512950c0d870f26.tar.bz2 | |
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/ipv4')
| -rw-r--r-- | net/ipv4/igmp.c | 18 | ||||
| -rw-r--r-- | net/ipv4/ip_sockglue.c | 19 |
2 files changed, 19 insertions, 18 deletions
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c index 47f0502b2101..7b272bbed2b4 100644 --- a/net/ipv4/igmp.c +++ b/net/ipv4/igmp.c @@ -2565,9 +2565,9 @@ done: } int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf, - struct group_filter __user *optval, int __user *optlen) + struct sockaddr_storage __user *p) { - int err, i, count, copycount; + int i, count, copycount; struct sockaddr_in *psin; __be32 addr; struct ip_mc_socklist *pmc; @@ -2583,37 +2583,29 @@ int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf, if (!ipv4_is_multicast(addr)) return -EINVAL; - err = -EADDRNOTAVAIL; - for_each_pmc_rtnl(inet, pmc) { if (pmc->multi.imr_multiaddr.s_addr == addr && pmc->multi.imr_ifindex == gsf->gf_interface) break; } if (!pmc) /* must have a prior join */ - goto done; + return -EADDRNOTAVAIL; gsf->gf_fmode = pmc->sfmode; psl = rtnl_dereference(pmc->sflist); count = psl ? psl->sl_count : 0; 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; - } - for (i = 0; i < copycount; i++) { + for (i = 0; i < copycount; i++, p++) { struct sockaddr_storage ss; psin = (struct sockaddr_in *)&ss; memset(&ss, 0, sizeof(ss)); psin->sin_family = AF_INET; psin->sin_addr.s_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; -done: - return err; } /* diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index 3c2c6cd3933b..e3703a3e7ef4 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -1473,19 +1473,28 @@ static int do_ip_getsockopt(struct sock *sk, int level, int optname, } 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; - if (len < GROUP_FILTER_SIZE(0)) { + if (len < size0) { err = -EINVAL; goto out; } - if (copy_from_user(&gsf, optval, GROUP_FILTER_SIZE(0))) { + if (copy_from_user(&gsf, p, size0)) { err = -EFAULT; goto out; } - err = ip_mc_gsfget(sk, &gsf, - (struct group_filter __user *)optval, - optlen); + num = gsf.gf_numsrc; + err = ip_mc_gsfget(sk, &gsf, p->gf_slist); + if (err) + goto out; + if (gsf.gf_numsrc < num) + num = gsf.gf_numsrc; + if (put_user(GROUP_FILTER_SIZE(num), optlen) || + copy_to_user(p, &gsf, size0)) + err = -EFAULT; goto out; } case IP_MULTICAST_ALL: |