drbd: Also need to check for DRBD_GENLA_F_MANDATORY flags before nla_find_nested()
This is done by introducing drbd_nla_find_nested() which handles the flag
before calling nla_find_nested().
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 5b4090f..24187f1 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -92,7 +92,7 @@
#define VOLUME_UNSPECIFIED (-1U)
/* pointer into the request skb,
* limited lifetime! */
- char *conn_name;
+ char *resource_name;
/* reply buffer */
struct sk_buff *reply_skb;
@@ -191,15 +191,15 @@
/* and assign stuff to the global adm_ctx */
nla = nested_attr_tb[__nla_type(T_ctx_volume)];
adm_ctx.volume = nla ? nla_get_u32(nla) : VOLUME_UNSPECIFIED;
- nla = nested_attr_tb[__nla_type(T_ctx_conn_name)];
+ nla = nested_attr_tb[__nla_type(T_ctx_resource_name)];
if (nla)
- adm_ctx.conn_name = nla_data(nla);
+ adm_ctx.resource_name = nla_data(nla);
} else
adm_ctx.volume = VOLUME_UNSPECIFIED;
adm_ctx.minor = d_in->minor;
adm_ctx.mdev = minor_to_mdev(d_in->minor);
- adm_ctx.tconn = conn_get_by_name(adm_ctx.conn_name);
+ adm_ctx.tconn = conn_get_by_name(adm_ctx.resource_name);
if (!adm_ctx.mdev && (flags & DRBD_ADM_NEED_MINOR)) {
drbd_msg_put_info("unknown minor");
@@ -214,7 +214,8 @@
if (adm_ctx.mdev && adm_ctx.tconn &&
adm_ctx.mdev->tconn != adm_ctx.tconn) {
pr_warning("request: minor=%u, conn=%s; but that minor belongs to connection %s\n",
- adm_ctx.minor, adm_ctx.conn_name, adm_ctx.mdev->tconn->name);
+ adm_ctx.minor, adm_ctx.resource_name,
+ adm_ctx.mdev->tconn->name);
drbd_msg_put_info("minor exists in different connection");
return ERR_INVALID_REQUEST;
}
@@ -239,7 +240,7 @@
static int drbd_adm_finish(struct genl_info *info, int retcode)
{
struct nlattr *nla;
- const char *conn_name = NULL;
+ const char *resource_name = NULL;
if (adm_ctx.tconn) {
kref_put(&adm_ctx.tconn->kref, &conn_destroy);
@@ -253,9 +254,10 @@
nla = info->attrs[DRBD_NLA_CFG_CONTEXT];
if (nla) {
- nla = nla_find_nested(nla, __nla_type(T_ctx_conn_name));
- if (nla)
- conn_name = nla_data(nla);
+ int maxtype = ARRAY_SIZE(drbd_cfg_context_nl_policy) - 1;
+ nla = drbd_nla_find_nested(maxtype, nla, __nla_type(T_ctx_resource_name));
+ if (nla && !IS_ERR(nla))
+ resource_name = nla_data(nla);
}
drbd_adm_send_reply(adm_ctx.reply_skb, info);
@@ -2526,7 +2528,7 @@
return drbd_adm_simple_request_state(skb, info, NS(disk, D_OUTDATED));
}
-int nla_put_drbd_cfg_context(struct sk_buff *skb, const char *conn_name, unsigned vnr)
+int nla_put_drbd_cfg_context(struct sk_buff *skb, const char *resource_name, unsigned vnr)
{
struct nlattr *nla;
nla = nla_nest_start(skb, DRBD_NLA_CFG_CONTEXT);
@@ -2534,7 +2536,7 @@
goto nla_put_failure;
if (vnr != VOLUME_UNSPECIFIED)
NLA_PUT_U32(skb, T_ctx_volume, vnr);
- NLA_PUT_STRING(skb, T_ctx_conn_name, conn_name);
+ NLA_PUT_STRING(skb, T_ctx_resource_name, resource_name);
nla_nest_end(skb, nla);
return 0;
@@ -2778,8 +2780,9 @@
{
const unsigned hdrlen = GENL_HDRLEN + GENL_MAGIC_FAMILY_HDRSZ;
struct nlattr *nla;
- const char *conn_name;
+ const char *resource_name;
struct drbd_tconn *tconn;
+ int maxtype;
/* Is this a followup call? */
if (cb->args[0]) {
@@ -2799,12 +2802,15 @@
/* No explicit context given. Dump all. */
if (!nla)
goto dump;
- nla = nla_find_nested(nla, __nla_type(T_ctx_conn_name));
+ maxtype = ARRAY_SIZE(drbd_cfg_context_nl_policy) - 1;
+ nla = drbd_nla_find_nested(maxtype, nla, __nla_type(T_ctx_resource_name));
+ if (IS_ERR(nla))
+ return PTR_ERR(nla);
/* context given, but no name present? */
if (!nla)
return -EINVAL;
- conn_name = nla_data(nla);
- tconn = conn_get_by_name(conn_name);
+ resource_name = nla_data(nla);
+ tconn = conn_get_by_name(resource_name);
if (!tconn)
return -ENODEV;
@@ -2957,16 +2963,16 @@
}
static enum drbd_ret_code
-drbd_check_conn_name(const char *name)
+drbd_check_resource_name(const char *name)
{
if (!name || !name[0]) {
- drbd_msg_put_info("connection name missing");
+ drbd_msg_put_info("resource name missing");
return ERR_MANDATORY_TAG;
}
/* if we want to use these in sysfs/configfs/debugfs some day,
* we must not allow slashes */
if (strchr(name, '/')) {
- drbd_msg_put_info("invalid connection name");
+ drbd_msg_put_info("invalid resource name");
return ERR_INVALID_REQUEST;
}
return NO_ERROR;
@@ -2982,7 +2988,7 @@
if (retcode != NO_ERROR)
goto out;
- retcode = drbd_check_conn_name(adm_ctx.conn_name);
+ retcode = drbd_check_resource_name(adm_ctx.resource_name);
if (retcode != NO_ERROR)
goto out;
@@ -2995,7 +3001,7 @@
goto out;
}
- if (!conn_create(adm_ctx.conn_name))
+ if (!conn_create(adm_ctx.resource_name))
retcode = ERR_NOMEM;
out:
drbd_adm_finish(info, retcode);
@@ -3213,3 +3219,53 @@
"Event seq:%u sib_reason:%u\n",
err, seq, sib->sib_reason);
}
+
+int drbd_nla_check_mandatory(int maxtype, struct nlattr *nla)
+{
+ struct nlattr *head = nla_data(nla);
+ int len = nla_len(nla);
+ int rem;
+
+ /*
+ * validate_nla (called from nla_parse_nested) ignores attributes
+ * beyond maxtype, and does not understand the DRBD_GENLA_F_MANDATORY flag.
+ * In order to have it validate attributes with the DRBD_GENLA_F_MANDATORY
+ * flag set also, check and remove that flag before calling
+ * nla_parse_nested.
+ */
+
+ nla_for_each_attr(nla, head, len, rem) {
+ if (nla->nla_type & DRBD_GENLA_F_MANDATORY) {
+ nla->nla_type &= ~DRBD_GENLA_F_MANDATORY;
+ if (nla_type(nla) > maxtype)
+ return -EOPNOTSUPP;
+ }
+ }
+ return 0;
+}
+
+int drbd_nla_parse_nested(struct nlattr *tb[], int maxtype, struct nlattr *nla,
+ const struct nla_policy *policy)
+{
+ int err;
+
+ err = drbd_nla_check_mandatory(maxtype, nla);
+ if (!err)
+ err = nla_parse_nested(tb, maxtype, nla, policy);
+
+ return err;
+}
+
+struct nlattr *drbd_nla_find_nested(int maxtype, struct nlattr *nla, int attrtype)
+{
+ int err;
+ /*
+ * If any nested attribute has the DRBD_GENLA_F_MANDATORY flag set and
+ * we don't know about that attribute, reject all the nested
+ * attributes.
+ */
+ err = drbd_nla_check_mandatory(maxtype, nla);
+ if (err)
+ return ERR_PTR(err);
+ return nla_find_nested(nla, attrtype);
+}