In function lowpan_header_create(), we invoke the following code
construct:
struct ipv6hdr *hdr;
...
hdr = ipv6_hdr(skb);
...
if (...)
memcpy(hc06_ptr + 1, &hdr->flow_lbl[1], 2);
else
memcpy(hc06_ptr, &hdr, 4);
Where the else path of the condition, that is, non-compression
path, calls memcpy() with a pointer to struct ipv6hdr *hdr as
source, thus two levels of indirection. This cannot be correct,
and likely only one level of pointer was intended as source
buffer for memcpy() here.
Fixes: 44331fe2aa ("IEEE802.15.4: 6LoWPAN basic support")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Werner Almesberger <werner@almesberger.net>
Signed-off-by: David S. Miller <davem@davemloft.net>