From fc910a27839584209726537698b596576940add4 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Sun, 25 Mar 2007 20:27:59 -0700 Subject: [NETLINK]: Limit NLMSG_GOODSIZE to 8K. Signed-off-by: David S. Miller --- include/linux/netlink.h | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'include/linux/netlink.h') diff --git a/include/linux/netlink.h b/include/linux/netlink.h index 2a20f488ac1..a9d3ad5bc80 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -171,9 +171,16 @@ int netlink_sendskb(struct sock *sk, struct sk_buff *skb, int protocol); /* * skb should fit one page. This choice is good for headerless malloc. + * But we should limit to 8K so that userspace does not have to + * use enormous buffer sizes on recvmsg() calls just to avoid + * MSG_TRUNC when PAGE_SIZE is very large. */ -#define NLMSG_GOODORDER 0 -#define NLMSG_GOODSIZE (SKB_MAX_ORDER(0, NLMSG_GOODORDER)) +#if PAGE_SIZE < 8192UL +#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(PAGE_SIZE) +#else +#define NLMSG_GOODSIZE SKB_WITH_OVERHEAD(8192UL) +#endif + #define NLMSG_DEFAULT_SIZE (NLMSG_GOODSIZE - NLMSG_HDRLEN) -- cgit v1.2.3 From 27a884dc3cb63b93c2b3b643f5b31eed5f8a4d26 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Thu, 19 Apr 2007 20:29:13 -0700 Subject: [SK_BUFF]: Convert skb->tail to sk_buff_data_t So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes on 64bit architectures, allowing us to combine the 4 bytes hole left by the layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4 64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN... :-) Many calculations that previously required that skb->{transport,network, mac}_header be first converted to a pointer now can be done directly, being meaningful as offsets or pointers. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- include/linux/netlink.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/netlink.h') diff --git a/include/linux/netlink.h b/include/linux/netlink.h index a9d3ad5bc80..68a632b372e 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -229,7 +229,7 @@ __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags) (cb)->nlh->nlmsg_seq, type, len, flags) #define NLMSG_END(skb, nlh) \ -({ (nlh)->nlmsg_len = (skb)->tail - (unsigned char *) (nlh); \ +({ (nlh)->nlmsg_len = skb_tail_pointer(skb) - (unsigned char *)(nlh); \ (skb)->len; }) #define NLMSG_CANCEL(skb, nlh) \ -- cgit v1.2.3 From b529ccf2799c14346d1518e9bdf1f88f03643e99 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Wed, 25 Apr 2007 19:08:35 -0700 Subject: [NETLINK]: Introduce nlmsg_hdr() helper For the common "(struct nlmsghdr *)skb->data" sequence, so that we reduce the number of direct accesses to skb->data and for consistency with all the other cast skb member helpers. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- include/linux/netlink.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/linux/netlink.h') diff --git a/include/linux/netlink.h b/include/linux/netlink.h index 68a632b372e..36629fff26d 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -138,6 +138,11 @@ struct nlattr #include #include +static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb) +{ + return (struct nlmsghdr *)skb->data; +} + struct netlink_skb_parms { struct ucred creds; /* Skb credentials */ -- cgit v1.2.3 From a36ca733375860b389c15ffdf6a5f92df64a33b6 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Mon, 19 Mar 2007 22:28:08 -0300 Subject: [NETLINK]: Remove NLMSG_{NEW_ANSWER,CANCEL,END} Not used anywhere and defined inside __KERNEL__, Thomas acked this on irc. Signed-off-by: Arnaldo Carvalho de Melo --- include/linux/netlink.h | 12 ------------ 1 file changed, 12 deletions(-) (limited to 'include/linux/netlink.h') diff --git a/include/linux/netlink.h b/include/linux/netlink.h index 36629fff26d..0d11f6a7389 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -229,18 +229,6 @@ __nlmsg_put(struct sk_buff *skb, u32 pid, u32 seq, int type, int len, int flags) #define NLMSG_PUT(skb, pid, seq, type, len) \ NLMSG_NEW(skb, pid, seq, type, len, 0) -#define NLMSG_NEW_ANSWER(skb, cb, type, len, flags) \ - NLMSG_NEW(skb, NETLINK_CB((cb)->skb).pid, \ - (cb)->nlh->nlmsg_seq, type, len, flags) - -#define NLMSG_END(skb, nlh) \ -({ (nlh)->nlmsg_len = skb_tail_pointer(skb) - (unsigned char *)(nlh); \ - (skb)->len; }) - -#define NLMSG_CANCEL(skb, nlh) \ -({ skb_trim(skb, (unsigned char *) (nlh) - (skb)->data); \ - -1; }) - extern int netlink_dump_start(struct sock *ssk, struct sk_buff *skb, struct nlmsghdr *nlh, int (*dump)(struct sk_buff *skb, struct netlink_callback*), -- cgit v1.2.3 From af65bdfce98d7965fbe93a48b8128444a2eea024 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Fri, 20 Apr 2007 14:14:21 -0700 Subject: [NETLINK]: Switch cb_lock spinlock to mutex and allow to override it Switch cb_lock to mutex and allow netlink kernel users to override it with a subsystem specific mutex for consistent locking in dump callbacks. All netlink_dump_start users have been audited not to rely on any side-effects of the previously used spinlock. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- include/linux/netlink.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'include/linux/netlink.h') diff --git a/include/linux/netlink.h b/include/linux/netlink.h index 0d11f6a7389..f41688f5663 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -157,7 +157,10 @@ struct netlink_skb_parms #define NETLINK_CREDS(skb) (&NETLINK_CB((skb)).creds) -extern struct sock *netlink_kernel_create(int unit, unsigned int groups, void (*input)(struct sock *sk, int len), struct module *module); +extern struct sock *netlink_kernel_create(int unit, unsigned int groups, + void (*input)(struct sock *sk, int len), + struct mutex *cb_mutex, + struct module *module); extern void netlink_ack(struct sk_buff *in_skb, struct nlmsghdr *nlh, int err); extern int netlink_has_listeners(struct sock *sk, unsigned int group); extern int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 pid, int nonblock); -- cgit v1.2.3