diff options
| -rw-r--r-- | include/net/netlink.h | 74 | ||||
| -rw-r--r-- | kernel/taskstats.c | 2 | ||||
| -rw-r--r-- | net/netlink/attr.c | 75 | ||||
| -rw-r--r-- | net/netlink/genetlink.c | 2 |
4 files changed, 141 insertions, 12 deletions
diff --git a/include/net/netlink.h b/include/net/netlink.h index 640c26a..3a5e40b 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -35,6 +35,8 @@ * nlmsg_put() add a netlink message to an skb * nlmsg_put_answer() callback based nlmsg_put() * nlmsg_end() finanlize netlink message + * nlmsg_get_pos() return current position in message + * nlmsg_trim() trim part of message * nlmsg_cancel() cancel message construction * nlmsg_free() free a netlink message * @@ -80,8 +82,10 @@ * struct nlattr netlink attribtue header * * Attribute Construction: - * nla_reserve(skb, type, len) reserve skb tailroom for an attribute + * nla_reserve(skb, type, len) reserve room for an attribute + * nla_reserve_nohdr(skb, len) reserve room for an attribute w/o hdr * nla_put(skb, type, len, data) add attribute to skb + * nla_put_nohdr(skb, len, data) add attribute w/o hdr * * Attribute Construction for Basic Types: * nla_put_u8(skb, type, value) add u8 attribute to skb @@ -139,6 +143,7 @@ * nla_next(nla, remaining) get next netlink attribute * nla_validate() validate a stream of attributes * nla_find() find attribute in stream of attributes + * nla_find_nested() find attribute in nested attributes * nla_parse() parse and validate stream of attrs * nla_parse_nested() parse nested attribuets * nla_for_each_attr() loop over all attributes @@ -203,12 +208,18 @@ extern int nla_memcmp(const struct nlattr *nla, const void *data, extern int nla_strcmp(const struct nlattr *nla, const char *str); extern struct nlattr * __nla_reserve(struct sk_buff *skb, int attrtype, int attrlen); +extern void * __nla_reserve_nohdr(struct sk_buff *skb, int attrlen); extern struct nlattr * nla_reserve(struct sk_buff *skb, int attrtype, int attrlen); +extern void * nla_reserve_nohdr(struct sk_buff *skb, int attrlen); extern void __nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data); +extern void __nla_put_nohdr(struct sk_buff *skb, int attrlen, + const void *data); extern int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data); +extern int nla_put_nohdr(struct sk_buff *skb, int attrlen, + const void *data); /************************************************************************** * Netlink Messages @@ -453,12 +464,13 @@ static inline struct nlmsghdr *nlmsg_put_answer(struct sk_buff *skb, /** * nlmsg_new - Allocate a new netlink message * @size: maximum size of message + * @flags: the type of memory to allocate. * * Use NLMSG_GOODSIZE if size isn't know and you need a good default size. */ -static inline struct sk_buff *nlmsg_new(int size) +static inline struct sk_buff *nlmsg_new(int size, gfp_t flags) { - return alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); + return alloc_skb(size, flags); } /** @@ -480,6 +492,32 @@ static inline int nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh) } /** + * nlmsg_get_pos - return current position in netlink message + * @skb: socket buffer the message is stored in + * + * Returns a pointer to the current tail of the message. + */ +static inline void *nlmsg_get_pos(struct sk_buff *skb) +{ + return skb->tail; +} + +/** + * nlmsg_trim - Trim message to a mark + * @skb: socket buffer the message is stored in + * @mark: mark to trim to + * + * Trims the message to the provided mark. Returns -1. + */ +static inline int nlmsg_trim(struct sk_buff *skb, void *mark) +{ + if (mark) + skb_trim(skb, (unsigned char *) mark - skb->data); + + return -1; +} + +/** * nlmsg_cancel - Cancel construction of a netlink message * @skb: socket buffer the message is stored in * @nlh: netlink message header @@ -489,9 +527,7 @@ static inline int nlmsg_end(struct sk_buff *skb, struct nlmsghdr *nlh) */ static inline int nlmsg_cancel(struct sk_buff *skb, struct nlmsghdr *nlh) { - skb_trim(skb, (unsigned char *) nlh - skb->data); - - return -1; + return nlmsg_trim(skb, nlh); } /** @@ -631,6 +667,18 @@ static inline struct nlattr *nla_next(const struct nlattr *nla, int *remaining) } /** + * nla_find_nested - find attribute in a set of nested attributes + * @nla: attribute containing the nested attributes + * @attrtype: type of attribute to look for + * + * Returns the first attribute which matches the specified type. + */ +static inline struct nlattr *nla_find_nested(struct nlattr *nla, int attrtype) +{ + return nla_find(nla_data(nla), nla_len(nla), attrtype); +} + +/** * nla_parse_nested - parse nested attributes * @tb: destination array with maxtype+1 elements * @maxtype: maximum attribute type to be expected @@ -862,10 +910,7 @@ static inline int nla_nest_end(struct sk_buff *skb, struct nlattr *start) */ static inline int nla_nest_cancel(struct sk_buff *skb, struct nlattr *start) { - if (start) - skb_trim(skb, (unsigned char *) start - skb->data); - - return -1; + return nlmsg_trim(skb, start); } /** @@ -880,4 +925,13 @@ static inline int nla_nest_cancel(struct sk_buff *skb, struct nlattr *start) nla_ok(pos, rem); \ pos = nla_next(pos, &(rem))) +/** + * nla_for_each_nested - iterate over nested attributes + * @pos: loop counter, set to current attribute + * @nla: attribute containing the nested attributes + * @rem: initialized to len, holds bytes currently remaining in stream + */ +#define nla_for_each_nested(pos, nla, rem) \ + nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem) + #endif diff --git a/kernel/taskstats.c b/kernel/taskstats.c index e781876..2ed4040 100644 --- a/kernel/taskstats.c +++ b/kernel/taskstats.c @@ -75,7 +75,7 @@ static int prepare_reply(struct genl_info *info, u8 cmd, struct sk_buff **skbp, /* * If new attributes are added, please revisit this allocation */ - skb = nlmsg_new(size); + skb = nlmsg_new(size, GFP_KERNEL); if (!skb) return -ENOMEM; diff --git a/net/netlink/attr.c b/net/netlink/attr.c index dddbd15..136e529 100644 --- a/net/netlink/attr.c +++ b/net/netlink/attr.c @@ -255,6 +255,26 @@ struct nlattr *__nla_reserve(struct sk_buff *skb, int attrtype, int attrlen) } /** + * __nla_reserve_nohdr - reserve room for attribute without header + * @skb: socket buffer to reserve room on + * @attrlen: length of attribute payload + * + * Reserves room for attribute payload without a header. + * + * The caller is responsible to ensure that the skb provides enough + * tailroom for the payload. + */ +void *__nla_reserve_nohdr(struct sk_buff *skb, int attrlen) +{ + void *start; + + start = skb_put(skb, NLA_ALIGN(attrlen)); + memset(start, 0, NLA_ALIGN(attrlen)); + + return start; +} + +/** * nla_reserve - reserve room for attribute on the skb * @skb: socket buffer to reserve room on * @attrtype: attribute type @@ -275,6 +295,24 @@ struct nlattr *nla_reserve(struct sk_buff *skb, int attrtype, int attrlen) } /** + * nla_reserve - reserve room for attribute without header + * @skb: socket buffer to reserve room on + * @len: length of attribute payload + * + * Reserves room for attribute payload without a header. + * + * Returns NULL if the tailroom of the skb is insufficient to store + * the attribute payload. + */ +void *nla_reserve_nohdr(struct sk_buff *skb, int attrlen) +{ + if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen))) + return NULL; + + return __nla_reserve_nohdr(skb, attrlen); +} + +/** * __nla_put - Add a netlink attribute to a socket buffer * @skb: socket buffer to add attribute to * @attrtype: attribute type @@ -293,6 +331,22 @@ void __nla_put(struct sk_buff *skb, int attrtype, int attrlen, memcpy(nla_data(nla), data, attrlen); } +/** + * __nla_put_nohdr - Add a netlink attribute without header + * @skb: socket buffer to add attribute to + * @attrlen: length of attribute payload + * @data: head of attribute payload + * + * The caller is responsible to ensure that the skb provides enough + * tailroom for the attribute payload. + */ +void __nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data) +{ + void *start; + + start = __nla_reserve_nohdr(skb, attrlen); + memcpy(start, data, attrlen); +} /** * nla_put - Add a netlink attribute to a socket buffer @@ -313,15 +367,36 @@ int nla_put(struct sk_buff *skb, int attrtype, int attrlen, const void *data) return 0; } +/** + * nla_put_nohdr - Add a netlink attribute without header + * @skb: socket buffer to add attribute to + * @attrlen: length of attribute payload + * @data: head of attribute payload + * + * Returns -1 if the tailroom of the skb is insufficient to store + * the attribute payload. + */ +int nla_put_nohdr(struct sk_buff *skb, int attrlen, const void *data) +{ + if (unlikely(skb_tailroom(skb) < NLA_ALIGN(attrlen))) + return -1; + + __nla_put_nohdr(skb, attrlen, data); + return 0; +} EXPORT_SYMBOL(nla_validate); EXPORT_SYMBOL(nla_parse); EXPORT_SYMBOL(nla_find); EXPORT_SYMBOL(nla_strlcpy); EXPORT_SYMBOL(__nla_reserve); +EXPORT_SYMBOL(__nla_reserve_nohdr); EXPORT_SYMBOL(nla_reserve); +EXPORT_SYMBOL(nla_reserve_nohdr); EXPORT_SYMBOL(__nla_put); +EXPORT_SYMBOL(__nla_put_nohdr); EXPORT_SYMBOL(nla_put); +EXPORT_SYMBOL(nla_put_nohdr); EXPORT_SYMBOL(nla_memcpy); EXPORT_SYMBOL(nla_memcmp); EXPORT_SYMBOL(nla_strcmp); diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index a298f77..75bb47a 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -440,7 +440,7 @@ static struct sk_buff *ctrl_build_msg(struct genl_family *family, u32 pid, struct sk_buff *skb; int err; - skb = nlmsg_new(NLMSG_GOODSIZE); + skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); if (skb == NULL) return ERR_PTR(-ENOBUFS); |