Valgrind reported this:
==14823== Invalid read of size 4
==14823== at 0x113FB9: memcpy (string_fortified.h:34)
==14823== by 0x113FB9: ethernet_fill_header (ethernet.c:483)
==14823== by 0x113FB9: ethernet_send (ethernet.c:588)
==14823== by 0x116720: net_if_tx (net_if.c:173)
==14823== by 0x116720: process_tx_packet (net_if.c:211)
==14823== by 0x10FDB6: z_work_q_main (work_q.c:32)
==14823== by 0x10FD55: _thread_entry (thread_entry.c:29)
==14823== by 0x111CF7: posix_thread_starter (posix_core.c:301)
==14823== by 0x49673BC: start_thread (pthread_create.c:463)
==14823== by 0x4A78E15: clone (clone.S:108)
==14823== Address 0x87822a6 is in a rw- anonymous segment
The issue is that we had a pointer that pointed to local stack
variable and that pointer was used to access stuff after the
test function had returned.
Fixes#12006
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>