Commit 7c3063cc authored by Andreas Gruenbacher's avatar Andreas Gruenbacher Committed by Philipp Reisner
Browse files

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: default avatarPhilipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: default avatarLars Ellenberg <lars.ellenberg@linbit.com>
parent 789c1b62

drivers/block/drbd/drbd_int.h

+6 −0
Original line number Diff line number Diff line
@@ -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);

drivers/block/drbd/drbd_nl.c

+76 −20
Original line number Diff line number Diff line
@@ -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 @@ static int drbd_adm_prepare(struct sk_buff *skb, struct genl_info *info, 
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 @@ int drbd_adm_new_c_uuid(struct sk_buff *skb, struct genl_info *info) 
}



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 @@ void drbd_bcast_event(struct drbd_conf *mdev, const struct sib_info *sib) 
			"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);

}

include/linux/drbd_genl.h

+1 −1
Original line number Diff line number Diff line
@@ -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,

include/linux/genl_magic_func.h

+0 −37
Original line number Diff line number Diff line
@@ -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 */		\