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_int.h b/drivers/block/drbd/drbd_int.h
index c3019730a24f793f1357dd36ada2d4c5afa53837..c58430183d5fcfc8e8d06905be9232adb0a4eb99 100644 (file)
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -1407,6 +1407,12 @@ extern bool conn_try_outdate_peer(struct drbd_tconn *tconn);
 extern void conn_try_outdate_peer_async(struct drbd_tconn *tconn);
 extern int drbd_khelper(struct drbd_conf *mdev, char *cmd);
 
+struct nla_policy;
+extern int drbd_nla_check_mandatory(int maxtype, struct nlattr *nla);
+extern int drbd_nla_parse_nested(struct nlattr *tb[], int maxtype, struct nlattr *nla,
+                                const struct nla_policy *policy);
+extern struct nlattr *drbd_nla_find_nested(int maxtype, struct nlattr *nla, int attrtype);
+
 /* drbd_worker.c */
 extern int drbd_worker(struct drbd_thread *thi);
 enum drbd_ret_code drbd_resync_after_valid(struct drbd_conf *mdev, int o_minor);

diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 5b4090f52f5ad1c203746a197fd2bc8528145134..24187f1c93d5918bcf472c3bedcee99ba86569fc 100644 (file)
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -92,7 +92,7 @@ static struct drbd_config_context {
 #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 @@ static int drbd_adm_prepare(struct sk_buff *skb, struct genl_info *info,
                /* 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 @@ static int drbd_adm_prepare(struct sk_buff *skb, struct genl_info *info,
        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 @@ fail:
 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 @@ static int drbd_adm_finish(struct genl_info *info, int retcode)
 
        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 @@ int drbd_adm_outdate(struct sk_buff *skb, struct genl_info *info)
        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 @@ int nla_put_drbd_cfg_context(struct sk_buff *skb, const char *conn_name, unsigne
                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 @@ int drbd_adm_get_status_all(struct sk_buff *skb, struct netlink_callback *cb)
 {
        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 @@ int drbd_adm_get_status_all(struct sk_buff *skb, struct netlink_callback *cb)
        /* 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 @@ out_nolock:
 }
 
 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 @@ int drbd_adm_new_resource(struct sk_buff *skb, struct genl_info *info)
        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 @@ int drbd_adm_new_resource(struct sk_buff *skb, struct genl_info *info)
                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 @@ failed:
                        "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);
+}

diff --git a/include/linux/drbd_genl.h b/include/linux/drbd_genl.h
index 47ef324b69db692e00426cba502b9158edeb4e3e..0c2102c05384f8ac2e8ce8b130bd7bf08dd374dc 100644 (file)
--- a/include/linux/drbd_genl.h
+++ b/include/linux/drbd_genl.h
@@ -96,7 +96,7 @@ GENL_struct(DRBD_NLA_CFG_REPLY, 1, drbd_cfg_reply,
  * and the volume id within the resource. */
 GENL_struct(DRBD_NLA_CFG_CONTEXT, 2, drbd_cfg_context,
        __u32_field(1, DRBD_GENLA_F_MANDATORY,  ctx_volume)
-       __str_field(2, DRBD_GENLA_F_MANDATORY,  ctx_conn_name, 128)
+       __str_field(2, DRBD_GENLA_F_MANDATORY,  ctx_resource_name, 128)
 )
 
 GENL_struct(DRBD_NLA_DISK_CONF, 3, disk_conf,

diff --git a/include/linux/genl_magic_func.h b/include/linux/genl_magic_func.h
index 357f2ad403b1d32a1e9ddd27b7c50ba92d0844bf..0b8a88e2e83ed45c5d0533964bca8d2c88b3cbe1 100644 (file)
--- a/include/linux/genl_magic_func.h
+++ b/include/linux/genl_magic_func.h
@@ -142,43 +142,6 @@ static struct nlattr *nested_attr_tb[128];
 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
 #endif
 
-static inline 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;
-}
-
-static inline 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;
-}
-
 #undef GENL_struct
 #define GENL_struct(tag_name, tag_number, s_name, s_fields)            \
 /* *_from_attrs functions are static, but potentially unused */                \