Re: [bug+patch] SCTP and chunk types over 0x1f

[Patrick McHardy <kaber@trash.net>]

Stephane Chazelas wrote:
> On Mon, Jun 25, 2007 at 03:08:39PM +0100, Stephane Chazelas wrote:
> 
>>>Does it stay completely compatible (modulo fixed bugs) then?
>>
>>AFAICT, yes (though I've not tested it). I don't know if the
>>kernel needs to be rebuilt for the bug to be fixed (that is, I
>>don't know whether in the kernel code there are some calls to
>>the SCTP_CHUNKMAP_IS_ALL_SET and cie macros with non-array
>>arguments, I don't think there are).
> 
> [...]
> 
> actually yes, the kernel is affected. See "return
> SCTP_CHUNKMAP_IS_CLEAR(chunkmap)" for instance in match_packet()
> in net/netfilter/xt_sctp.c, chunkmap is u_int32_t*, so
> ARRAY_SIZE(chunkmap) will return
> sizeof(u_int32_t*)/sizeof(u_int32_t) that is probably 1 or 2
> instead of 64 or 8.
> 
> The fixed iptable should work with either a fixed or non-fixed
> kernel. However, with a non-fixed kernel, it will not fix the
> bug completely.


Thats fine, bugs in the kernel need a new kernel of course.
The important thing is that userspace compatibility of old
binaries is not affected. So the kernel just needs the
new xt_sctp file?