[NETFILTER] x_tables: fix compat related crash on non-x86
[linux-3.10.git] / net / ipv4 / netfilter / ip_tables.c
index d25ac8b..6d1c115 100644 (file)
@@ -956,15 +956,16 @@ struct compat_ipt_standard_target
        compat_int_t verdict;
 };
 
-#define IPT_ST_OFFSET  (sizeof(struct ipt_standard_target) - \
-                               sizeof(struct compat_ipt_standard_target))
-
 struct compat_ipt_standard
 {
        struct compat_ipt_entry entry;
        struct compat_ipt_standard_target target;
 };
 
+#define IPT_ST_LEN             XT_ALIGN(sizeof(struct ipt_standard_target))
+#define IPT_ST_COMPAT_LEN      COMPAT_XT_ALIGN(sizeof(struct compat_ipt_standard_target))
+#define IPT_ST_OFFSET          (IPT_ST_LEN - IPT_ST_COMPAT_LEN)
+
 static int compat_ipt_standard_fn(void *target,
                void **dstptr, int *size, int convert)
 {
@@ -975,35 +976,29 @@ static int compat_ipt_standard_fn(void *target,
        ret = 0;
        switch (convert) {
                case COMPAT_TO_USER:
-                       pst = (struct ipt_standard_target *)target;
+                       pst = target;
                        memcpy(&compat_st.target, &pst->target,
-                                       sizeof(struct ipt_entry_target));
+                               sizeof(compat_st.target));
                        compat_st.verdict = pst->verdict;
                        if (compat_st.verdict > 0)
                                compat_st.verdict -=
                                        compat_calc_jump(compat_st.verdict);
-                       compat_st.target.u.user.target_size =
-                       sizeof(struct compat_ipt_standard_target);
-                       if (__copy_to_user(*dstptr, &compat_st,
-                               sizeof(struct compat_ipt_standard_target)))
+                       compat_st.target.u.user.target_size = IPT_ST_COMPAT_LEN;
+                       if (copy_to_user(*dstptr, &compat_st, IPT_ST_COMPAT_LEN))
                                ret = -EFAULT;
                        *size -= IPT_ST_OFFSET;
-                       *dstptr += sizeof(struct compat_ipt_standard_target);
+                       *dstptr += IPT_ST_COMPAT_LEN;
                        break;
                case COMPAT_FROM_USER:
-                       pcompat_st =
-                               (struct compat_ipt_standard_target *)target;
-                       memcpy(&st.target, &pcompat_st->target,
-                                       sizeof(struct ipt_entry_target));
+                       pcompat_st = target;
+                       memcpy(&st.target, &pcompat_st->target, IPT_ST_COMPAT_LEN);
                        st.verdict = pcompat_st->verdict;
                        if (st.verdict > 0)
                                st.verdict += compat_calc_jump(st.verdict);
-                       st.target.u.user.target_size =
-                       sizeof(struct ipt_standard_target);
-                       memcpy(*dstptr, &st,
-                                       sizeof(struct ipt_standard_target));
+                       st.target.u.user.target_size = IPT_ST_LEN;
+                       memcpy(*dstptr, &st, IPT_ST_LEN);
                        *size += IPT_ST_OFFSET;
-                       *dstptr += sizeof(struct ipt_standard_target);
+                       *dstptr += IPT_ST_LEN;
                        break;
                case COMPAT_CALC_SIZE:
                        *size += IPT_ST_OFFSET;