[PATCH v4.10] netfilter: nf_conntrack_h323: lost .data_len definition for Q.931/ipv6

[PATCH v4.10] netfilter: nf_conntrack_h323: lost .data_len definition for Q.931/ipv6

[Vasily Averin]

Could you please push this patch into stable@?
it fixes memory corruption in kernels  v3.5 .. v4.10

Lost .data_len definition leads to write beyond end of
struct nf_ct_h323_master. Usually it corrupts following
struct nf_conn_nat, however if nat is not loaded it corrupts
following slab object.

In mainline this problem went away in v4.11,
after commit 9f0f3ebeda47 ("netfilter: helpers: remove data_len usage
for inkernel helpers") however many stable kernels are still affected.

cc: stable@vger.kernel.org
Fixes: 1afc56794e03 ("netfilter: nf_ct_helper: implement variable length helper private data") # v3.5
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
---
 net/netfilter/nf_conntrack_h323_main.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/netfilter/nf_conntrack_h323_main.c b/net/netfilter/nf_conntrack_h323_main.c
index f65d93639d12..29fe1e7eac88 100644
--- a/net/netfilter/nf_conntrack_h323_main.c
+++ b/net/netfilter/nf_conntrack_h323_main.c
@@ -1225,6 +1225,7 @@ static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
 	{
 		.name			= "Q.931",
 		.me			= THIS_MODULE,
+		.data_len		= sizeof(struct nf_ct_h323_master),
 		.tuple.src.l3num	= AF_INET6,
 		.tuple.src.u.tcp.port	= cpu_to_be16(Q931_PORT),
 		.tuple.dst.protonum	= IPPROTO_TCP,
-- 
2.17.1

Re: [PATCH v4.10] netfilter: nf_conntrack_h323: lost .data_len definition for Q.931/ipv6

[Florian Westphal]

Vasily Averin <vvs@virtuozzo.com> wrote:
> Could you please push this patch into stable@?
> it fixes memory corruption in kernels  v3.5 .. v4.10
> 
> Lost .data_len definition leads to write beyond end of
> struct nf_ct_h323_master. Usually it corrupts following
> struct nf_conn_nat, however if nat is not loaded it corrupts
> following slab object.
> 
> In mainline this problem went away in v4.11,
> after commit 9f0f3ebeda47 ("netfilter: helpers: remove data_len usage
> for inkernel helpers") however many stable kernels are still affected.
> 
> cc: stable@vger.kernel.org
> Fixes: 1afc56794e03 ("netfilter: nf_ct_helper: implement variable length helper private data") # v3.5
> Signed-off-by: Vasily Averin <vvs@virtuozzo.com>

Reviewed-by: Florian Westphal <fw@strlen.de>

Re: [PATCH v4.10] netfilter: nf_conntrack_h323: lost .data_len definition for Q.931/ipv6

[Pablo Neira Ayuso]

CC'ing stable@vger.kernel.org

On Tue, Jun 09, 2020 at 10:53:22AM +0300, Vasily Averin wrote:
> Could you please push this patch into stable@?
> it fixes memory corruption in kernels  v3.5 .. v4.10
> 
> Lost .data_len definition leads to write beyond end of
> struct nf_ct_h323_master. Usually it corrupts following
> struct nf_conn_nat, however if nat is not loaded it corrupts
> following slab object.
> 
> In mainline this problem went away in v4.11,
> after commit 9f0f3ebeda47 ("netfilter: helpers: remove data_len usage
> for inkernel helpers") however many stable kernels are still affected.

-stable maintainers of: 3.16, 4.4 and 4.9.

Please apply this patch, thanks.

> cc: stable@vger.kernel.org
> Fixes: 1afc56794e03 ("netfilter: nf_ct_helper: implement variable length helper private data") # v3.5
> Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
> ---
>  net/netfilter/nf_conntrack_h323_main.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/net/netfilter/nf_conntrack_h323_main.c b/net/netfilter/nf_conntrack_h323_main.c
> index f65d93639d12..29fe1e7eac88 100644
> --- a/net/netfilter/nf_conntrack_h323_main.c
> +++ b/net/netfilter/nf_conntrack_h323_main.c
> @@ -1225,6 +1225,7 @@ static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
>  	{
>  		.name			= "Q.931",
>  		.me			= THIS_MODULE,
> +		.data_len		= sizeof(struct nf_ct_h323_master),
>  		.tuple.src.l3num	= AF_INET6,
>  		.tuple.src.u.tcp.port	= cpu_to_be16(Q931_PORT),
>  		.tuple.dst.protonum	= IPPROTO_TCP,
> -- 
> 2.17.1
> 

Re: [PATCH v4.10] netfilter: nf_conntrack_h323: lost .data_len definition for Q.931/ipv6

[Vasily Averin]

On 6/24/20 3:12 PM, Pablo Neira Ayuso wrote:
> CC'ing stable@vger.kernel.org
> 
> On Tue, Jun 09, 2020 at 10:53:22AM +0300, Vasily Averin wrote:
>> Could you please push this patch into stable@?
>> it fixes memory corruption in kernels  v3.5 .. v4.10
>>
>> Lost .data_len definition leads to write beyond end of
>> struct nf_ct_h323_master. Usually it corrupts following
>> struct nf_conn_nat, however if nat is not loaded it corrupts
>> following slab object.
>>
>> In mainline this problem went away in v4.11,
>> after commit 9f0f3ebeda47 ("netfilter: helpers: remove data_len usage
>> for inkernel helpers") however many stable kernels are still affected.
> 
> -stable maintainers of: 3.16, 4.4 and 4.9.
> 
> Please apply this patch, thanks.

It fixes CVE-2020-14305
https://access.redhat.com/security/cve/CVE-2020-14305

>> cc: stable@vger.kernel.org
>> Fixes: 1afc56794e03 ("netfilter: nf_ct_helper: implement variable length helper private data") # v3.5
>> Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
>> ---
>>  net/netfilter/nf_conntrack_h323_main.c | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/net/netfilter/nf_conntrack_h323_main.c b/net/netfilter/nf_conntrack_h323_main.c
>> index f65d93639d12..29fe1e7eac88 100644
>> --- a/net/netfilter/nf_conntrack_h323_main.c
>> +++ b/net/netfilter/nf_conntrack_h323_main.c
>> @@ -1225,6 +1225,7 @@ static struct nf_conntrack_helper nf_conntrack_helper_q931[] __read_mostly = {
>>  	{
>>  		.name			= "Q.931",
>>  		.me			= THIS_MODULE,
>> +		.data_len		= sizeof(struct nf_ct_h323_master),
>>  		.tuple.src.l3num	= AF_INET6,
>>  		.tuple.src.u.tcp.port	= cpu_to_be16(Q931_PORT),
>>  		.tuple.dst.protonum	= IPPROTO_TCP,
>> -- 
>> 2.17.1
>>

Re: [PATCH v4.10] netfilter: nf_conntrack_h323: lost .data_len definition for Q.931/ipv6

[Greg KH]

On Wed, Jun 24, 2020 at 02:12:32PM +0200, Pablo Neira Ayuso wrote:
> CC'ing stable@vger.kernel.org
> 
> On Tue, Jun 09, 2020 at 10:53:22AM +0300, Vasily Averin wrote:
> > Could you please push this patch into stable@?
> > it fixes memory corruption in kernels  v3.5 .. v4.10
> > 
> > Lost .data_len definition leads to write beyond end of
> > struct nf_ct_h323_master. Usually it corrupts following
> > struct nf_conn_nat, however if nat is not loaded it corrupts
> > following slab object.
> > 
> > In mainline this problem went away in v4.11,
> > after commit 9f0f3ebeda47 ("netfilter: helpers: remove data_len usage
> > for inkernel helpers") however many stable kernels are still affected.
> 
> -stable maintainers of: 3.16, 4.4 and 4.9.

Now queued up to 4.4 and 4.9, thanks.  3.16 is end-of-life.

greg k-h