Hi Glenn,

On Tue, 2016-05-31 at 12:23 +0200, Glenn Ruben Bakke wrote:

Backport for v4.5 and v4.6 of
commit 55441070ca1cbd47ce1ad2959bbf4b47aed9b83b upstream.

The memcpy of ipv6 header destination address to the skb control
block
(sbk->cb) in header_create() results in currupted memory when
bt_xmit()
is issued. The skb->cb is "released" in the return of header_create()
making room for lower layer to minipulate the skb->cb.

The value retrieved in bt_xmit is not persistent across header
creation
and sending, and the lower layer will overwrite portions of skb->cb,
making the copied destination address wrong.

The memory corruption will lead to non-working multicast as the first
4
bytes of the copied destination address is replaced by a value that
resolves into a non-multicast prefix.

This fix removes the dependency on the skb control block between
header
creation and send, by moving the destination address memcpy to the
send
function path (setup_create, which is called from bt_xmit).

Signed-off-by: Glenn Ruben Bakke <redacted>
---

Acked-by: Jukka Rissanen <redacted>


Cheers,
Jukka