diff options
Diffstat (limited to 'net/netfilter/x_tables.c')
-rw-r--r-- | net/netfilter/x_tables.c | 68 |
1 files changed, 58 insertions, 10 deletions
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index 2ff499680cc6..016db6be94b9 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -262,6 +262,60 @@ struct xt_target *xt_request_find_target(u8 af, const char *name, u8 revision) } EXPORT_SYMBOL_GPL(xt_request_find_target); + +static int xt_obj_to_user(u16 __user *psize, u16 size, + void __user *pname, const char *name, + u8 __user *prev, u8 rev) +{ + if (put_user(size, psize)) + return -EFAULT; + if (copy_to_user(pname, name, strlen(name) + 1)) + return -EFAULT; + if (put_user(rev, prev)) + return -EFAULT; + + return 0; +} + +#define XT_OBJ_TO_USER(U, K, TYPE, C_SIZE) \ + xt_obj_to_user(&U->u.TYPE##_size, C_SIZE ? : K->u.TYPE##_size, \ + U->u.user.name, K->u.kernel.TYPE->name, \ + &U->u.user.revision, K->u.kernel.TYPE->revision) + +int xt_data_to_user(void __user *dst, const void *src, + int usersize, int size) +{ + usersize = usersize ? : size; + if (copy_to_user(dst, src, usersize)) + return -EFAULT; + if (usersize != size && clear_user(dst + usersize, size - usersize)) + return -EFAULT; + + return 0; +} +EXPORT_SYMBOL_GPL(xt_data_to_user); + +#define XT_DATA_TO_USER(U, K, TYPE, C_SIZE) \ + xt_data_to_user(U->data, K->data, \ + K->u.kernel.TYPE->usersize, \ + C_SIZE ? : K->u.kernel.TYPE->TYPE##size) + +int xt_match_to_user(const struct xt_entry_match *m, + struct xt_entry_match __user *u) +{ + return XT_OBJ_TO_USER(u, m, match, 0) || + XT_DATA_TO_USER(u, m, match, 0); +} +EXPORT_SYMBOL_GPL(xt_match_to_user); + +int xt_target_to_user(const struct xt_entry_target *t, + struct xt_entry_target __user *u) +{ + return XT_OBJ_TO_USER(u, t, target, 0) || + XT_DATA_TO_USER(u, t, target, 0); +} +EXPORT_SYMBOL_GPL(xt_target_to_user); + static int match_revfn(u8 af, const char *name, u8 revision, int *bestp) { const struct xt_match *m; @@ -565,17 +619,14 @@ int xt_compat_match_to_user(const struct xt_entry_match *m, int off = xt_compat_match_offset(match); u_int16_t msize = m->u.user.match_size - off; - if (copy_to_user(cm, m, sizeof(*cm)) || - put_user(msize, &cm->u.user.match_size) || - copy_to_user(cm->u.user.name, m->u.kernel.match->name, - strlen(m->u.kernel.match->name) + 1)) + if (XT_OBJ_TO_USER(cm, m, match, msize)) return -EFAULT; if (match->compat_to_user) { if (match->compat_to_user((void __user *)cm->data, m->data)) return -EFAULT; } else { - if (copy_to_user(cm->data, m->data, msize - sizeof(*cm))) + if (XT_DATA_TO_USER(cm, m, match, msize - sizeof(*cm))) return -EFAULT; } @@ -923,17 +974,14 @@ int xt_compat_target_to_user(const struct xt_entry_target *t, int off = xt_compat_target_offset(target); u_int16_t tsize = t->u.user.target_size - off; - if (copy_to_user(ct, t, sizeof(*ct)) || - put_user(tsize, &ct->u.user.target_size) || - copy_to_user(ct->u.user.name, t->u.kernel.target->name, - strlen(t->u.kernel.target->name) + 1)) + if (XT_OBJ_TO_USER(ct, t, target, tsize)) return -EFAULT; if (target->compat_to_user) { if (target->compat_to_user((void __user *)ct->data, t->data)) return -EFAULT; } else { - if (copy_to_user(ct->data, t->data, tsize - sizeof(*ct))) + if (XT_DATA_TO_USER(ct, t, target, tsize - sizeof(*ct))) return -EFAULT; } |