[PATCHv3 ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[PATCHv3 ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[Fan Du]

structure like xfrm_usersa_info or xfrm_userpolicy_info
has different sizeof when compiled as 32bits and 64bits
due to not appending pack attribute in their definition.
This will result in broken SA and SP information when user
trying to configure them through netlink interface.

Inform user land about this situation instead of keeping
silent, the upper test scripts would behave accordingly.

Quotes from: http://marc.info/?l=linux-netdev&m=142226348715503&w=2
>
> Before a clean solution show up, I think it's better to warn user in some way
> like http://patchwork.ozlabs.org/patch/323842/ did. Otherwise, many people
> who stuck there will always spend time and try to fix this issue in whatever way.

Yes, this is the first thing we should do. I'm willing to accept a patch

Signed-off-by: Fan Du <fan.du@intel.com>
---
ChangeLog:
v3:
  - Use -ENOTSUPP to honor error code rules 
v2:
  - Rebase with latest tree

---
 net/xfrm/xfrm_user.c |    5 +++++
 1 file changed, 5 insertions(+)

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 8128594..f960bd9 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -2419,6 +2419,11 @@ static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 	const struct xfrm_link *link;
 	int type, err;
 
+#ifdef CONFIG_COMPAT
+	if (is_compat_task())
+		return -ENOTSUPP;
+#endif
+
 	type = nlh->nlmsg_type;
 	if (type > XFRM_MSG_MAX)
 		return -EINVAL;
-- 
1.7.9.5

RE: [PATCHv3 ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[David Laight]

From: Fan Du
> structure like xfrm_usersa_info or xfrm_userpolicy_info
> has different sizeof when compiled as 32bits and 64bits
> due to not appending pack attribute in their definition.

Don't 'pack' the structure, just ensure that all the fields
are fixed sized and on their natural boundary.

Possibly add a compile-time check that the structure is
of the expected size.

	David

Re: [PATCHv3 ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[Florian Westphal]

David Laight <David.Laight@ACULAB.COM> wrote:
> From: Fan Du
> > structure like xfrm_usersa_info or xfrm_userpolicy_info
> > has different sizeof when compiled as 32bits and 64bits
> > due to not appending pack attribute in their definition.
> 
> Don't 'pack' the structure, just ensure that all the fields
> are fixed sized and on their natural boundary.

How do you propose to do this without breaking ABI?

> Possibly add a compile-time check that the structure is
> of the expected size.

Uh, what?

RE: [PATCHv3 ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[David Laight]

From: Florian Westphal 
> David Laight <David.Laight@ACULAB.COM> wrote:
> > From: Fan Du
> > > structure like xfrm_usersa_info or xfrm_userpolicy_info
> > > has different sizeof when compiled as 32bits and 64bits
> > > due to not appending pack attribute in their definition.
> >
> > Don't 'pack' the structure, just ensure that all the fields
> > are fixed sized and on their natural boundary.
> 
> How do you propose to do this without breaking ABI?

You may already have an ABI fubar.
Adding __packed won't make it go away.
IIRC your modified structure did have all its 64bit items
aligned on 8 byte boundaries - so the __packed wouldn't affect
the structure layout.

The problem is that you can't add that field when the ABI
only requires 4 byte alignment for 64bit items.

If you need to access a structure from (eg) an i386 application
within an amd64 kernel then you can add __attribute__((aligned(4)))
to any 64bit member to force that member to have only 4 byte aligment.
On 64bit systems that can't do misaligned transfers (eg sparc64)
that will result in two 32bit accesses for that member.
(You'll need to do it to all 64bit members if the structure
size needs to be an odd multiple of 4.)

> > Possibly add a compile-time check that the structure is
> > of the expected size.
> 
> Uh, what?

eg something based on:

typedef foo_check char[sizeof foo == 32 ? 1 : -1];

There will be a standard define for this somewhere
(and for the align attribute).

	David

Re: [PATCHv3 ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[David Miller]

From: David Laight <David.Laight@ACULAB.COM>
Date: Tue, 27 Jan 2015 09:46:21 +0000

> From: Fan Du
>> structure like xfrm_usersa_info or xfrm_userpolicy_info
>> has different sizeof when compiled as 32bits and 64bits
>> due to not appending pack attribute in their definition.
> 
> Don't 'pack' the structure, just ensure that all the fields
> are fixed sized and on their natural boundary.

This horse went out of the door more than a decade ago, we can't
change the layout of any of these structures and must at some point
add code to translate instead.

RE: [PATCHv3 ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[David Laight]

From: David Miller
> From: David Laight <David.Laight@ACULAB.COM>
> Date: Tue, 27 Jan 2015 09:46:21 +0000
> 
> > From: Fan Du
> >> structure like xfrm_usersa_info or xfrm_userpolicy_info
> >> has different sizeof when compiled as 32bits and 64bits
> >> due to not appending pack attribute in their definition.
> >
> > Don't 'pack' the structure, just ensure that all the fields
> > are fixed sized and on their natural boundary.
> 
> This horse went out of the door more than a decade ago, we can't
> change the layout of any of these structures and must at some point
> add code to translate instead.

>From the other mail it might just be tail-padding.
So any adaption code is easy.

	David

Re: [PATCHv3 ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[Fan Du]

于 2015年01月27日 17:46, David Laight 写道:
> From: Fan Du
>> structure like xfrm_usersa_info or xfrm_userpolicy_info
>> has different sizeof when compiled as 32bits and 64bits
>> due to not appending pack attribute in their definition.
>
> Don't 'pack' the structure, just ensure that all the fields
> are fixed sized and on their natural boundary.

Is that simple??

The layout is exactly the same between 32bits and 64bits, only difference
is the last cache line padding, because even if last cache line is not fully
occupied, but at least use even bytes, not odd bytes. I think this relates
to cache HW behaviour, not how the structure is naturally aligned or not.
Actually, the structure members is aligned indeed.

#### 64bits
struct xfrm_usersa_info {
     struct xfrm_selector       sel;                  /*     0    56 */
     struct xfrm_id             id;                   /*    56    24 */

     /* XXX last struct has 3 bytes of padding */

     /* --- cacheline 1 boundary (64 bytes) was 16 bytes ago --- */
     xfrm_address_t             saddr;                /*    80    16 */
     struct xfrm_lifetime_cfg   lft;                  /*    96    64 */
     /* --- cacheline 2 boundary (128 bytes) was 32 bytes ago --- */
     struct xfrm_lifetime_cur   curlft;               /*   160    32 */
     /* --- cacheline 3 boundary (192 bytes) --- */
     struct xfrm_stats          stats;                /*   192    12 */
     __u32                      seq;                  /*   204     4 */
     __u32                      reqid;                /*   208     4 */
     __u16                      family;               /*   212     2 */
     __u8                       mode;                 /*   214     1 */
     __u8                       replay_window;        /*   215     1 */
     __u8                       flags;                /*   216     1 */

     /* size: 224, cachelines: 4, members: 12 */
     /* padding: 7 */
     /* paddings: 1, sum paddings: 3 */
     /* last cacheline: 32 bytes */
};


#### 32bits
struct xfrm_usersa_info {
     struct xfrm_selector       sel;                  /*     0    56 */
     struct xfrm_id             id;                   /*    56    24 */

     /* XXX last struct has 3 bytes of padding */

     /* --- cacheline 1 boundary (64 bytes) was 16 bytes ago --- */
     xfrm_address_t             saddr;                /*    80    16 */
     struct xfrm_lifetime_cfg   lft;                  /*    96    64 */
     /* --- cacheline 2 boundary (128 bytes) was 32 bytes ago --- */
     struct xfrm_lifetime_cur   curlft;               /*   160    32 */
     /* --- cacheline 3 boundary (192 bytes) --- */
     struct xfrm_stats          stats;                /*   192    12 */
     __u32                      seq;                  /*   204     4 */
     __u32                      reqid;                /*   208     4 */
     __u16                      family;               /*   212     2 */
     __u8                       mode;                 /*   214     1 */
     __u8                       replay_window;        /*   215     1 */
     __u8                       flags;                /*   216     1 */

     /* size: 220, cachelines: 4, members: 12 */
     /* padding: 3 */
     /* paddings: 1, sum paddings: 3 */
     /* last cacheline: 28 bytes */
};

> Possibly add a compile-time check that the structure is
> of the expected size.
>
> 	David
>


-- 
No zuo no die but I have to try.

Re: [PATCHv3, ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[Nicolas Dichtel]

Le 27/01/2015 10:00, Fan Du a écrit :
> structure like xfrm_usersa_info or xfrm_userpolicy_info
> has different sizeof when compiled as 32bits and 64bits
> due to not appending pack attribute in their definition.
> This will result in broken SA and SP information when user
> trying to configure them through netlink interface.
>
> Inform user land about this situation instead of keeping
> silent, the upper test scripts would behave accordingly.
>
> Quotes from: http://marc.info/?l=linux-netdev&m=142226348715503&w=2
>>
>> Before a clean solution show up, I think it's better to warn user in some way
>> like http://patchwork.ozlabs.org/patch/323842/ did. Otherwise, many people
>> who stuck there will always spend time and try to fix this issue in whatever way.
>
> Yes, this is the first thing we should do. I'm willing to accept a patch
>
> Signed-off-by: Fan Du <fan.du@intel.com>
A way to solve this problem was to provide to userland a xfrm compat header
file, which match the ABI of the kernel. Something like:

#include <linux/xfrm.h>

#define xfrm_usersa_info xfrm_usersa_info_64
#define xfrm_usersa_info_compat xfrm_usersa_info
struct xfrm_usersa_info_compat {
	struct xfrm_selector		sel;
	struct xfrm_id			id;
	xfrm_address_t			saddr;
	struct xfrm_lifetime_cfg	lft;
	struct xfrm_lifetime_cur	curlft;
	struct xfrm_stats		stats;
	__u32				seq;
	__u32				reqid;
	__u16				family;
	__u8				mode;
	__u8				replay_window;
	__u8				flags;
	__u8				hole1;
	__u32				hole2;
};

The point I try to make is that patching userland apps allows to use xfrm on a
32bits userland / 64bits kernel.

If I understand well your patch, it will not be possible anymore, all messages
will be rejected. And this may break existing apps.


Regards,
Nicolas

RE: [PATCHv3, ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[David Laight]

From: Nicolas Dichtel
> Le 27/01/2015 10:00, Fan Du a crit :
> > structure like xfrm_usersa_info or xfrm_userpolicy_info
> > has different sizeof when compiled as 32bits and 64bits
> > due to not appending pack attribute in their definition.
> > This will result in broken SA and SP information when user
> > trying to configure them through netlink interface.
> >
> > Inform user land about this situation instead of keeping
> > silent, the upper test scripts would behave accordingly.
> >
> > Quotes from: http://marc.info/?l=linux-netdev&m=142226348715503&w=2
> >>
> >> Before a clean solution show up, I think it's better to warn user in some way
> >> like http://patchwork.ozlabs.org/patch/323842/ did. Otherwise, many people
> >> who stuck there will always spend time and try to fix this issue in whatever way.
> >
> > Yes, this is the first thing we should do. I'm willing to accept a patch
> >
> > Signed-off-by: Fan Du <fan.du@intel.com>
> A way to solve this problem was to provide to userland a xfrm compat header
> file, which match the ABI of the kernel. Something like:
> 
> #include <linux/xfrm.h>
> 
> #define xfrm_usersa_info xfrm_usersa_info_64
> #define xfrm_usersa_info_compat xfrm_usersa_info
> struct xfrm_usersa_info_compat {
> 	struct xfrm_selector		sel;
> 	struct xfrm_id			id;
> 	xfrm_address_t			saddr;
> 	struct xfrm_lifetime_cfg	lft;
> 	struct xfrm_lifetime_cur	curlft;
> 	struct xfrm_stats		stats;
> 	__u32				seq;
> 	__u32				reqid;
> 	__u16				family;
> 	__u8				mode;
> 	__u8				replay_window;
> 	__u8				flags;
> 	__u8				hole1;
> 	__u32				hole2;
> };
> 
> The point I try to make is that patching userland apps allows to use xfrm on a
> 32bits userland / 64bits kernel.
> 
> If I understand well your patch, it will not be possible anymore, all messages
> will be rejected. And this may break existing apps.

Probably OTT in this case.
IIRC the only actual difference if the 'end padding'.
So the wrapper need only ensure the copyin/out isn't too long.
Probably worth compile-time checks for the size.
If the structure is being copied to user then zero values need assigning
to the pad fields (unless read from user).

	David

Re: [PATCHv3, ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[Nicolas Dichtel]

Le 29/01/2015 14:56, David Laight a écrit :
> From: Nicolas Dichtel
>> Le 27/01/2015 10:00, Fan Du a crit :
>>> structure like xfrm_usersa_info or xfrm_userpolicy_info
>>> has different sizeof when compiled as 32bits and 64bits
>>> due to not appending pack attribute in their definition.
>>> This will result in broken SA and SP information when user
>>> trying to configure them through netlink interface.
>>>
>>> Inform user land about this situation instead of keeping
>>> silent, the upper test scripts would behave accordingly.
>>>
>>> Quotes from: http://marc.info/?l=linux-netdev&m=142226348715503&w=2
>>>>
>>>> Before a clean solution show up, I think it's better to warn user in some way
>>>> like http://patchwork.ozlabs.org/patch/323842/ did. Otherwise, many people
>>>> who stuck there will always spend time and try to fix this issue in whatever way.
>>>
>>> Yes, this is the first thing we should do. I'm willing to accept a patch
>>>
>>> Signed-off-by: Fan Du <fan.du@intel.com>
>> A way to solve this problem was to provide to userland a xfrm compat header
>> file, which match the ABI of the kernel. Something like:
>>
>> #include <linux/xfrm.h>
>>
>> #define xfrm_usersa_info xfrm_usersa_info_64
>> #define xfrm_usersa_info_compat xfrm_usersa_info
>> struct xfrm_usersa_info_compat {
>> 	struct xfrm_selector		sel;
>> 	struct xfrm_id			id;
>> 	xfrm_address_t			saddr;
>> 	struct xfrm_lifetime_cfg	lft;
>> 	struct xfrm_lifetime_cur	curlft;
>> 	struct xfrm_stats		stats;
>> 	__u32				seq;
>> 	__u32				reqid;
>> 	__u16				family;
>> 	__u8				mode;
>> 	__u8				replay_window;
>> 	__u8				flags;
>> 	__u8				hole1;
>> 	__u32				hole2;
>> };
>>
>> The point I try to make is that patching userland apps allows to use xfrm on a
>> 32bits userland / 64bits kernel.
>>
>> If I understand well your patch, it will not be possible anymore, all messages
>> will be rejected. And this may break existing apps.
>
> Probably OTT in this case.
> IIRC the only actual difference if the 'end padding'.
> So the wrapper need only ensure the copyin/out isn't too long.
It was just an example for one struct. Some other structures need to be
patched (eg struct xfrm_userspi_info uses struct xfrm_usersa_info).
And some attributes may follow this structure which will be padded to
be aligned.
The point was more to show that the existing interface can be used (and cannot
be used after the patch).

Regards,
Nicolas

Re: [PATCHv3, ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[Fan Du]

于 2015年01月29日 18:29, Nicolas Dichtel 写道:
> Le 27/01/2015 10:00, Fan Du a écrit :
>> structure like xfrm_usersa_info or xfrm_userpolicy_info
>> has different sizeof when compiled as 32bits and 64bits
>> due to not appending pack attribute in their definition.
>> This will result in broken SA and SP information when user
>> trying to configure them through netlink interface.
>>
>> Inform user land about this situation instead of keeping
>> silent, the upper test scripts would behave accordingly.
>>
>> Quotes from: http://marc.info/?l=linux-netdev&m=142226348715503&w=2
>>>
>>> Before a clean solution show up, I think it's better to warn user in some way
>>> like http://patchwork.ozlabs.org/patch/323842/ did. Otherwise, many people
>>> who stuck there will always spend time and try to fix this issue in whatever way.
>>
>> Yes, this is the first thing we should do. I'm willing to accept a patch
>>
>> Signed-off-by: Fan Du <fan.du@intel.com>
> A way to solve this problem was to provide to userland a xfrm compat header
> file, which match the ABI of the kernel. Something like:
>
> #include <linux/xfrm.h>
>
> #define xfrm_usersa_info xfrm_usersa_info_64
> #define xfrm_usersa_info_compat xfrm_usersa_info
> struct xfrm_usersa_info_compat {
>      struct xfrm_selector        sel;
>      struct xfrm_id            id;
>      xfrm_address_t            saddr;
>      struct xfrm_lifetime_cfg    lft;
>      struct xfrm_lifetime_cur    curlft;
>      struct xfrm_stats        stats;
>      __u32                seq;
>      __u32                reqid;
>      __u16                family;
>      __u8                mode;
>      __u8                replay_window;
>      __u8                flags;
>      __u8                hole1;
>      __u32                hole2;
> };
>
> The point I try to make is that patching userland apps allows to use xfrm on a
> 32bits userland / 64bits kernel.
>
> If I understand well your patch, it will not be possible anymore, all messages
> will be rejected. And this may break existing apps.

Add padding in user space does not fix existing 32bits ip binary, moreover not sure all other ARCHes
require the same padding. Maillist has various of proposals AFAICT, all is rejected for reasons
whatever for a very long time including padding user space structure. In fact those structures
are exposed by uapi from kernel to userspace.

Speaking of "break", run 32bits ip xfrm {state/policy/monitor} is _already_ broken on 64bits host.
This patch is making user not stumble there by seeing invalid xfrm information and wondering what's
going on. They can switch to setkey temporally.

last, thanks for your comments after looking at the code...

>
> Regards,
> Nicolas

Re: [PATCHv3, ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[Steffen Klassert]

On Thu, Jan 29, 2015 at 11:29:51AM +0100, Nicolas Dichtel wrote:
> A way to solve this problem was to provide to userland a xfrm compat header
> file, which match the ABI of the kernel. Something like:
> 
> #include <linux/xfrm.h>
> 
> #define xfrm_usersa_info xfrm_usersa_info_64
> #define xfrm_usersa_info_compat xfrm_usersa_info
> struct xfrm_usersa_info_compat {
> 	struct xfrm_selector		sel;
> 	struct xfrm_id			id;
> 	xfrm_address_t			saddr;
> 	struct xfrm_lifetime_cfg	lft;
> 	struct xfrm_lifetime_cur	curlft;
> 	struct xfrm_stats		stats;
> 	__u32				seq;
> 	__u32				reqid;
> 	__u16				family;
> 	__u8				mode;
> 	__u8				replay_window;
> 	__u8				flags;
> 	__u8				hole1;
> 	__u32				hole2;
> };
> 
> The point I try to make is that patching userland apps allows to use xfrm on a
> 32bits userland / 64bits kernel.

Ugh, I did not know that this is used that way. Which applications do this?
So the situation is worse than I thought. What happens to such applications
if we add a compat layer in the kernel? I'd guess they will break, right?

> 
> If I understand well your patch, it will not be possible anymore, all messages
> will be rejected. And this may break existing apps.

This patch would have been a quick solution without the case you
mentioned. Now I fear we can't fix all cases, something will remain
broken.

Re: [PATCHv3, ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[Nicolas Dichtel]

Le 02/02/2015 09:44, Steffen Klassert a écrit :
> On Thu, Jan 29, 2015 at 11:29:51AM +0100, Nicolas Dichtel wrote:
[snip]
>>
>> The point I try to make is that patching userland apps allows to use xfrm on a
>> 32bits userland / 64bits kernel.
>
> Ugh, I did not know that this is used that way. Which applications do this?
> So the situation is worse than I thought. What happens to such applications
> if we add a compat layer in the kernel? I'd guess they will break, right?
A compat layer will be perfect. I just wanted to highlight the fact that without
this patch, it's possible to have a workaround to use netlink-xfrm and after it,
it will be impossible.

>
>>
>> If I understand well your patch, it will not be possible anymore, all messages
>> will be rejected. And this may break existing apps.
>
> This patch would have been a quick solution without the case you
> mentioned. Now I fear we can't fix all cases, something will remain
> broken.
>
I think you're right, but having a proper solution is probably the best.

Re: [PATCHv3, ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[David Miller]

From: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Date: Mon, 02 Feb 2015 10:02:50 +0100

> Le 02/02/2015 09:44, Steffen Klassert a écrit :
>> On Thu, Jan 29, 2015 at 11:29:51AM +0100, Nicolas Dichtel wrote:
> [snip]
>>>
>>> The point I try to make is that patching userland apps allows to use
>>> xfrm on a
>>> 32bits userland / 64bits kernel.
>>
>> Ugh, I did not know that this is used that way. Which applications do
>> this?
>> So the situation is worse than I thought. What happens to such
>> applications
>> if we add a compat layer in the kernel? I'd guess they will break,
>> right?
>
> A compat layer will be perfect. I just wanted to highlight the fact
> that without this patch, it's possible to have a workaround to use
> netlink-xfrm and after it, it will be impossible.

Just a little history, there was a case where we tried to work around this
in userspace by messing with the structure definitions when building
the userland binaries, and that completely exploded.  This was with
the wireless extensions about 15 years ago.

If you work around it in userspace, then you can't fix the kernel to
do the right thing without potentially breaking things again for
the work around binaries that have been created.

Re: [PATCHv3, ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[Steffen Klassert]

On Mon, Feb 02, 2015 at 10:02:50AM +0100, Nicolas Dichtel wrote:
> Le 02/02/2015 09:44, Steffen Klassert a écrit :
> >On Thu, Jan 29, 2015 at 11:29:51AM +0100, Nicolas Dichtel wrote:
> [snip]
> >>
> >>The point I try to make is that patching userland apps allows to use xfrm on a
> >>32bits userland / 64bits kernel.
> >
> >Ugh, I did not know that this is used that way. Which applications do this?
> >So the situation is worse than I thought. What happens to such applications
> >if we add a compat layer in the kernel? I'd guess they will break, right?
> A compat layer will be perfect. I just wanted to highlight the fact that without
> this patch, it's possible to have a workaround to use netlink-xfrm and after it,
> it will be impossible.

You did not answer my question about the applications that do this.
If it is just possible, but there are no actual users, we should
apply this patch as soon as possible to avoid any abuse of this ABI.

I tend to apply this patch unless you can come up with a real world
application that will break if we do so.

Re: [PATCHv3, ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[Nicolas Dichtel]

Le 03/02/2015 13:24, Steffen Klassert a écrit :
> On Mon, Feb 02, 2015 at 10:02:50AM +0100, Nicolas Dichtel wrote:
>
> I tend to apply this patch unless you can come up with a real world
> application that will break if we do so.
It's a custom patch made for strongswan (not included upstream).

My suggestion was to display an error message instead of rejecting the message.
But fair enough, let's apply this patch, it will force people to come up with a
proper solution.

Re: [PATCHv3 ipsec-next] xfrm: Do not parse 32bits compiled xfrm netlink msg on 64bits host

[Steffen Klassert]

On Tue, Jan 27, 2015 at 05:00:29PM +0800, Fan Du wrote:
> structure like xfrm_usersa_info or xfrm_userpolicy_info
> has different sizeof when compiled as 32bits and 64bits
> due to not appending pack attribute in their definition.
> This will result in broken SA and SP information when user
> trying to configure them through netlink interface.
> 
> Inform user land about this situation instead of keeping
> silent, the upper test scripts would behave accordingly.
> 
> Quotes from: http://marc.info/?l=linux-netdev&m=142226348715503&w=2
> >
> > Before a clean solution show up, I think it's better to warn user in some way
> > like http://patchwork.ozlabs.org/patch/323842/ did. Otherwise, many people
> > who stuck there will always spend time and try to fix this issue in whatever way.
> 
> Yes, this is the first thing we should do. I'm willing to accept a patch
> 
> Signed-off-by: Fan Du <fan.du@intel.com>

Now applied to ipsec-next, thanks a lot Fan!