diff options
| -rw-r--r-- | net/bridge/netfilter/ebtables.c | 34 |
1 files changed, 24 insertions, 10 deletions
diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index fcaefdd6200b..dfb58056a89a 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -1428,16 +1428,12 @@ static int copy_everything_to_user(struct ebt_table *t, void __user *user, oldcounters = t->table->counters; } - if (copy_from_user(&tmp, user, sizeof(tmp))) { - BUGPRINT("Cfu didn't work\n"); + if (copy_from_user(&tmp, user, sizeof(tmp))) return -EFAULT; - } if (*len != sizeof(struct ebt_replace) + entries_size + - (tmp.num_counters? nentries * sizeof(struct ebt_counter): 0)) { - BUGPRINT("Wrong size\n"); + (tmp.num_counters? nentries * sizeof(struct ebt_counter): 0)) return -EINVAL; - } if (tmp.nentries != nentries) { BUGPRINT("Nentries wrong\n"); @@ -2213,8 +2209,12 @@ static int compat_do_replace(struct net *net, void __user *user, void *entries_tmp; ret = compat_copy_ebt_replace_from_user(&tmp, user, len); - if (ret) + if (ret) { + /* try real handler in case userland supplied needed padding */ + if (ret == -EINVAL && do_replace(net, user, len) == 0) + ret = 0; return ret; + } countersize = COUNTER_OFFSET(tmp.nentries) * nr_cpu_ids; newinfo = vmalloc(sizeof(*newinfo) + countersize); @@ -2303,8 +2303,9 @@ static int compat_update_counters(struct net *net, void __user *user, if (copy_from_user(&hlp, user, sizeof(hlp))) return -EFAULT; + /* try real handler in case userland supplied needed padding */ if (len != sizeof(hlp) + hlp.num_counters * sizeof(struct ebt_counter)) - return -EINVAL; + return update_counters(net, user, len); return do_update_counters(net, hlp.name, compat_ptr(hlp.counters), hlp.num_counters, user, len); @@ -2341,9 +2342,10 @@ static int compat_do_ebt_get_ctl(struct sock *sk, int cmd, if (!capable(CAP_NET_ADMIN)) return -EPERM; + /* try real handler in case userland supplied needed padding */ if ((cmd == EBT_SO_GET_INFO || cmd == EBT_SO_GET_INIT_INFO) && *len != sizeof(tmp)) - return -EINVAL; + return do_ebt_get_ctl(sk, cmd, user, len); if (copy_from_user(&tmp, user, sizeof(tmp))) return -EFAULT; @@ -2380,7 +2382,19 @@ static int compat_do_ebt_get_ctl(struct sock *sk, int cmd, break; case EBT_SO_GET_ENTRIES: case EBT_SO_GET_INIT_ENTRIES: - ret = compat_copy_everything_to_user(t, user, len, cmd); + /* + * try real handler first in case of userland-side padding. + * in case we are dealing with an 'ordinary' 32 bit binary + * without 64bit compatibility padding, this will fail right + * after copy_from_user when the *len argument is validated. + * + * the compat_ variant needs to do one pass over the kernel + * data set to adjust for size differences before it the check. + */ + if (copy_everything_to_user(t, user, len, cmd) == 0) + ret = 0; + else + ret = compat_copy_everything_to_user(t, user, len, cmd); break; default: ret = -EINVAL; |