DF-2295: fw_read iso over-read; ring=4chunk/8packet/512psize, peer stream.len=508, read=512 (uid=1002 gid=1002)
DF-2295: stream up; DMA ring allocated by real fwdma_malloc_multiseg
DF-2295: READY -- root injects packet now (3s window)
DF-2295: read() returned 512 (errno=0)
DF-2295: returned packet header = 01fc01a0 (len=508 tcode=a sy/chtag=a0)
DF-2295: copied 512 bytes; slot capacity 512 -> 0 bytes beyond the packet slot
DF-2295: attributed 0/4 bytes of the beyond-slot region to known ring-slot canary content
DF-2295: leak_sample.txt written
DF-2295: NOT_REPRODUCED