CVE Request: netfilter: remote memory corruption in nf_conntrack_proto_dccp.c

[Marcus Meissner <meissner () suse de>]

Hi,

via twitter/grsecurity, needs a CVE I guess.

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/net/netfilter/nf_conntrack_proto_dccp.c?id=b22f5126a24b3b2f15448c3f2a254fc10cbc2b92

commit b22f5126a24b3b2f15448c3f2a254fc10cbc2b92
Author: Daniel Borkmann <dborkman () redhat com>
Date:   Mon Jan 6 00:57:54 2014 +0100

    netfilter: nf_conntrack_dccp: fix skb_header_pointer API usages
    
    Some occurences in the netfilter tree use skb_header_pointer() in
    the following way ...
    
      struct dccp_hdr _dh, *dh;
      ...
      skb_header_pointer(skb, dataoff, sizeof(_dh), &dh);
    
    ... where dh itself is a pointer that is being passed as the copy
    buffer. Instead, we need to use &_dh as the forth argument so that
    we're copying the data into an actual buffer that sits on the stack.
    
    Currently, we probably could overwrite memory on the stack (e.g.
    with a possibly mal-formed DCCP packet), but unintentionally, as
    we only want the buffer to be placed into _dh variable.

is already in original commit on March 20, 2008, in 2.6.25.

Ciao, Marcus