[PATCH 0/3 net-2.6.26] ip_options_compile cleaning

[PATCH 0/3 net-2.6.26] ip_options_compile cleaning

[Denis V. Lunev]

Dave,

I have separated yesterday patch we have discussed into three parts to
make it a bit clearer for the future readers.

Regards,
    Den

[PATCH 1/3 net-2.6.26] [IPV4]: Remove unnecessary check for opt->is_data in ip_options_compile.

[Denis V. Lunev]

There is the only way to reach ip_options compile with opt != NULL:

ip_options_get_finish
    opt->is_data = 1;
    ip_options_compile(opt, NULL)

So, checking for is_data inside opt != NULL branch is not needed.

Signed-off-by: Denis V. Lunev <den@openvz.org>
---
 net/ipv4/ip_options.c |    3 +--
 1 files changed, 1 insertions(+), 2 deletions(-)

diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c
index baaedd9..d03eec6 100644
--- a/net/ipv4/ip_options.c
+++ b/net/ipv4/ip_options.c
@@ -267,8 +267,7 @@ int ip_options_compile(struct ip_options * opt, struct sk_buff * skb)
 		optptr = iph + sizeof(struct iphdr);
 		opt->is_data = 0;
 	} else {
-		optptr = opt->is_data ? opt->__data :
-					(unsigned char *)&(ip_hdr(skb)[1]);
+		optptr = opt->__data;
 		iph = optptr - sizeof(struct iphdr);
 	}
 
-- 
1.5.3.rc5

Re: [PATCH 1/3 net-2.6.26] [IPV4]: Remove unnecessary check for opt->is_data in ip_options_compile.

[Paul Moore]

On Tuesday 04 March 2008 7:22:04 am Denis V. Lunev wrote:
> There is the only way to reach ip_options compile with opt != NULL:
>
> ip_options_get_finish
>     opt->is_data = 1;
>     ip_options_compile(opt, NULL)
>
> So, checking for is_data inside opt != NULL branch is not needed.
>
> Signed-off-by: Denis V. Lunev <den@openvz.org>
> ---
>  net/ipv4/ip_options.c |    3 +--
>  1 files changed, 1 insertions(+), 2 deletions(-)
>
> diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c
> index baaedd9..d03eec6 100644
> --- a/net/ipv4/ip_options.c
> +++ b/net/ipv4/ip_options.c
> @@ -267,8 +267,7 @@ int ip_options_compile(struct ip_options * opt,
> struct sk_buff * skb) optptr = iph + sizeof(struct iphdr);
>  		opt->is_data = 0;
>  	} else {
> -		optptr = opt->is_data ? opt->__data :
> -					(unsigned char *)&(ip_hdr(skb)[1]);
> +		optptr = opt->__data;
>  		iph = optptr - sizeof(struct iphdr);
>  	}

I personally think this patch should be combined with path #2; if we 
aren't going to honor the 'is_data' field we shouldn't give any callers 
false hope.

-- 
paul moore
linux security @ hp

[PATCH 2/3 net-2.6.26] [IPV4]: Remove unused ip_options->is_data.

[Denis V. Lunev]

ip_options->is_data is assigned only and never checked. The structure is
not a part of kernel interface to the user. So, it is safe to remove this
field.

Signed-off-by: Denis V. Lunev <den@openvz.org>
---
 include/net/inet_sock.h |    3 +--
 net/ipv4/cipso_ipv4.c   |    1 -
 net/ipv4/ip_options.c   |    5 -----
 3 files changed, 1 insertions(+), 8 deletions(-)

diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index 70013c5..07ce114 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -43,8 +43,7 @@ struct ip_options {
 	unsigned char	srr;
 	unsigned char	rr;
 	unsigned char	ts;
-	unsigned char	is_data:1,
-			is_strictroute:1,
+	unsigned char	is_strictroute:1,
 			srr_is_hit:1,
 			is_changed:1,
 			rr_needaddr:1,
diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index 8cd357f..4637ded 100644
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -1800,7 +1800,6 @@ int cipso_v4_sock_setattr(struct sock *sk,
 	}
 	memcpy(opt->__data, buf, buf_len);
 	opt->optlen = opt_len;
-	opt->is_data = 1;
 	opt->cipso = sizeof(struct iphdr);
 	kfree(buf);
 	buf = NULL;
diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c
index d03eec6..0bf097b 100644
--- a/net/ipv4/ip_options.c
+++ b/net/ipv4/ip_options.c
@@ -45,7 +45,6 @@ void ip_options_build(struct sk_buff * skb, struct ip_options * opt,
 	memcpy(&(IPCB(skb)->opt), opt, sizeof(struct ip_options));
 	memcpy(iph+sizeof(struct iphdr), opt->__data, opt->optlen);
 	opt = &(IPCB(skb)->opt);
-	opt->is_data = 0;
 
 	if (opt->srr)
 		memcpy(iph+opt->srr+iph[opt->srr+1]-4, &daddr, 4);
@@ -95,8 +94,6 @@ int ip_options_echo(struct ip_options * dopt, struct sk_buff * skb)
 
 	memset(dopt, 0, sizeof(struct ip_options));
 
-	dopt->is_data = 1;
-
 	sopt = &(IPCB(skb)->opt);
 
 	if (sopt->optlen == 0) {
@@ -265,7 +262,6 @@ int ip_options_compile(struct ip_options * opt, struct sk_buff * skb)
 		iph = skb_network_header(skb);
 		opt->optlen = ((struct iphdr *)iph)->ihl*4 - sizeof(struct iphdr);
 		optptr = iph + sizeof(struct iphdr);
-		opt->is_data = 0;
 	} else {
 		optptr = opt->__data;
 		iph = optptr - sizeof(struct iphdr);
@@ -519,7 +515,6 @@ static int ip_options_get_finish(struct ip_options **optp,
 	while (optlen & 3)
 		opt->__data[optlen++] = IPOPT_END;
 	opt->optlen = optlen;
-	opt->is_data = 1;
 	if (optlen && ip_options_compile(opt, NULL)) {
 		kfree(opt);
 		return -EINVAL;
-- 
1.5.3.rc5

Re: [PATCH 2/3 net-2.6.26] [IPV4]: Remove unused ip_options->is_data.

[Paul Moore]

On Tuesday 04 March 2008 7:22:05 am Denis V. Lunev wrote:
> ip_options->is_data is assigned only and never checked. The structure
> is not a part of kernel interface to the user. So, it is safe to
> remove this field.
>
> Signed-off-by: Denis V. Lunev <den@openvz.org>

See my previous comment about folding patch #1 into this one.  Other 
than that I don't have any problem with changes from a CIPSO point of 
view with the current code base.  If we need to do something crazy in 
the future with IPv4 options we can always tackle it then. 

> ---
>  include/net/inet_sock.h |    3 +--
>  net/ipv4/cipso_ipv4.c   |    1 -
>  net/ipv4/ip_options.c   |    5 -----
>  3 files changed, 1 insertions(+), 8 deletions(-)
>
> diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
> index 70013c5..07ce114 100644
> --- a/include/net/inet_sock.h
> +++ b/include/net/inet_sock.h
> @@ -43,8 +43,7 @@ struct ip_options {
>  	unsigned char	srr;
>  	unsigned char	rr;
>  	unsigned char	ts;
> -	unsigned char	is_data:1,
> -			is_strictroute:1,
> +	unsigned char	is_strictroute:1,
>  			srr_is_hit:1,
>  			is_changed:1,
>  			rr_needaddr:1,
> diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
> index 8cd357f..4637ded 100644
> --- a/net/ipv4/cipso_ipv4.c
> +++ b/net/ipv4/cipso_ipv4.c
> @@ -1800,7 +1800,6 @@ int cipso_v4_sock_setattr(struct sock *sk,
>  	}
>  	memcpy(opt->__data, buf, buf_len);
>  	opt->optlen = opt_len;
> -	opt->is_data = 1;
>  	opt->cipso = sizeof(struct iphdr);
>  	kfree(buf);
>  	buf = NULL;
> diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c
> index d03eec6..0bf097b 100644
> --- a/net/ipv4/ip_options.c
> +++ b/net/ipv4/ip_options.c
> @@ -45,7 +45,6 @@ void ip_options_build(struct sk_buff * skb, struct
> ip_options * opt, memcpy(&(IPCB(skb)->opt), opt, sizeof(struct
> ip_options)); memcpy(iph+sizeof(struct iphdr), opt->__data,
> opt->optlen); opt = &(IPCB(skb)->opt);
> -	opt->is_data = 0;
>
>  	if (opt->srr)
>  		memcpy(iph+opt->srr+iph[opt->srr+1]-4, &daddr, 4);
> @@ -95,8 +94,6 @@ int ip_options_echo(struct ip_options * dopt,
> struct sk_buff * skb)
>
>  	memset(dopt, 0, sizeof(struct ip_options));
>
> -	dopt->is_data = 1;
> -
>  	sopt = &(IPCB(skb)->opt);
>
>  	if (sopt->optlen == 0) {
> @@ -265,7 +262,6 @@ int ip_options_compile(struct ip_options * opt,
> struct sk_buff * skb) iph = skb_network_header(skb);
>  		opt->optlen = ((struct iphdr *)iph)->ihl*4 - sizeof(struct iphdr);
>  		optptr = iph + sizeof(struct iphdr);
> -		opt->is_data = 0;
>  	} else {
>  		optptr = opt->__data;
>  		iph = optptr - sizeof(struct iphdr);
> @@ -519,7 +515,6 @@ static int ip_options_get_finish(struct
> ip_options **optp, while (optlen & 3)
>  		opt->__data[optlen++] = IPOPT_END;
>  	opt->optlen = optlen;
> -	opt->is_data = 1;
>  	if (optlen && ip_options_compile(opt, NULL)) {
>  		kfree(opt);
>  		return -EINVAL;



-- 
paul moore
linux security @ hp

[PATCH 3/3 net-2.6.26] [IPV4]: Always pass ip_options pointer into ip_options_compile.

[Denis V. Lunev]

This makes code a bit more uniform and straigthforward.

Signed-off-by: Denis V. Lunev <den@openvz.org>
---
 net/ipv4/ip_input.c   |    5 +++--
 net/ipv4/ip_options.c |   17 +++++++----------
 2 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 6563139..a006c0f 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -283,13 +283,14 @@ static inline int ip_rcv_options(struct sk_buff *skb)
 	}
 
 	iph = ip_hdr(skb);
+	opt = &(IPCB(skb)->opt);
+	opt->optlen = iph->ihl*4 - sizeof(struct iphdr);
 
-	if (ip_options_compile(NULL, skb)) {
+	if (ip_options_compile(opt, skb)) {
 		IP_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
 		goto drop;
 	}
 
-	opt = &(IPCB(skb)->opt);
 	if (unlikely(opt->srr)) {
 		struct in_device *in_dev = in_dev_get(dev);
 		if (in_dev) {
diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c
index 0bf097b..2b45a7d 100644
--- a/net/ipv4/ip_options.c
+++ b/net/ipv4/ip_options.c
@@ -255,17 +255,14 @@ int ip_options_compile(struct ip_options * opt, struct sk_buff * skb)
 	unsigned char * optptr;
 	int optlen;
 	unsigned char * pp_ptr = NULL;
-	struct rtable *rt = skb ? (struct rtable*)skb->dst : NULL;
-
-	if (!opt) {
-		opt = &(IPCB(skb)->opt);
-		iph = skb_network_header(skb);
-		opt->optlen = ((struct iphdr *)iph)->ihl*4 - sizeof(struct iphdr);
-		optptr = iph + sizeof(struct iphdr);
-	} else {
+	struct rtable *rt = NULL;
+
+	if (skb != NULL) {
+		rt = (struct rtable*)skb->dst;
+		optptr = (unsigned char *)&(ip_hdr(skb)[1]);
+	} else
 		optptr = opt->__data;
-		iph = optptr - sizeof(struct iphdr);
-	}
+	iph = optptr - sizeof(struct iphdr);
 
 	for (l = opt->optlen; l > 0; ) {
 		switch (*optptr) {
-- 
1.5.3.rc5

Re: [PATCH 0/3 net-2.6.26] ip_options_compile cleaning

[Denis V. Lunev]

On Tue, 2008-03-04 at 15:21 +0300, Denis V. Lunev wrote:
> I have separated yesterday patch we have discussed into three parts to
> make it a bit clearer for the future readers.

Dave,

it looks like this set of patches is not gone into the git. Should I
re-send them?

Regards,
	Den

Re: [PATCH 0/3 net-2.6.26] ip_options_compile cleaning

[David Miller]

From: "Denis V. Lunev" <den@parallels.com>
Date: Tue, 18 Mar 2008 17:38:27 +0300

> On Tue, 2008-03-04 at 15:21 +0300, Denis V. Lunev wrote:
> > I have separated yesterday patch we have discussed into three parts to
> > make it a bit clearer for the future readers.
> 
> Dave,
> 
> it looks like this set of patches is not gone into the git. Should I
> re-send them?

I expected you to resend them, yes.