Re: [PATCH net] net: filter: fix SKF_AD_PKTTYPE extension on big-endian

From: Alexei Starovoitov <redacted>
Date: Thu,  5 Jun 2014 14:39:36 -0700

BPF classic->internal converter broke SKF_AD_PKTTYPE extension, since
pkt_type_offset() was failing to find skb->pkt_type field which is defined as:
__u8 pkt_type:3,
     fclone:2,
     ipvs_property:1,
     peeked:1,
     nf_trace:1;

Fix it by searching for 3 most significant bits and shift them by 5 at run-time

Fixes: bd4cf0ed331a ("net: filter: rework/optimize internal BPF interpreter's instruction set")
Signed-off-by: Alexei Starovoitov <redacted>
Acked-by: Daniel Borkmann <redacted>
Tested-by: Daniel Borkmann <redacted>
---

backported BPF testsuite to 'net' and tested with qemu-sparc64.
Daniel tested it on s390.

Dave,
The fix doesn't apply cleanly to 'net-next'.
There 2nd hunk needs to be:
               insn++;
               *insn = BPF_ALU32_IMM(BPF_RSH, BPF_REG_A, 5);
I have 'net-next' patch ready and tested as well. Let me know if I should
send it or you'll take care of it while doing the merge of 'net'.

Applied, and I'll take care of this when I merge net into net-next,
thanks.