From ef146fa40cc3af1dcb13688f41cc06a9c0deb01c Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Wed, 23 Sep 2015 21:56:47 +0200 Subject: [PATCH] cls_bpf: make binding to classid optional The binding to a particular classid was so far always mandatory for cls_bpf, but it doesn't need to be. Therefore, lift this restriction as similarly done in other classifiers. Only a couple of qdiscs make use of class from the tcf_result, others don't strictly care, so let the user choose his needs (those that read out class can handle situations where it could be NULL). An explicit check for tcf_unbind_filter() is also not needed here, as the previous r->class was 0, so the xchg() will return that and therefore a callback to the qdisc's unbind_tcf() is skipped. Signed-off-by: Daniel Borkmann Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller --- net/sched/cls_bpf.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/net/sched/cls_bpf.c b/net/sched/cls_bpf.c index 7d9241545188..d6c0a0b44afb 100644 --- a/net/sched/cls_bpf.c +++ b/net/sched/cls_bpf.c @@ -307,14 +307,11 @@ static int cls_bpf_modify_existing(struct net *net, struct tcf_proto *tp, { bool is_bpf, is_ebpf, have_exts = false; struct tcf_exts exts; - u32 classid; int ret; is_bpf = tb[TCA_BPF_OPS_LEN] && tb[TCA_BPF_OPS]; is_ebpf = tb[TCA_BPF_FD]; - - if ((!is_bpf && !is_ebpf) || (is_bpf && is_ebpf) || - !tb[TCA_BPF_CLASSID]) + if ((!is_bpf && !is_ebpf) || (is_bpf && is_ebpf)) return -EINVAL; tcf_exts_init(&exts, TCA_BPF_ACT, TCA_BPF_POLICE); @@ -322,7 +319,6 @@ static int cls_bpf_modify_existing(struct net *net, struct tcf_proto *tp, if (ret < 0) return ret; - classid = nla_get_u32(tb[TCA_BPF_CLASSID]); if (tb[TCA_BPF_FLAGS]) { u32 bpf_flags = nla_get_u32(tb[TCA_BPF_FLAGS]); @@ -334,7 +330,6 @@ static int cls_bpf_modify_existing(struct net *net, struct tcf_proto *tp, have_exts = bpf_flags & TCA_BPF_FLAG_ACT_DIRECT; } - prog->res.classid = classid; prog->exts_integrated = have_exts; ret = is_bpf ? cls_bpf_prog_from_ops(tb, prog) : @@ -344,9 +339,12 @@ static int cls_bpf_modify_existing(struct net *net, struct tcf_proto *tp, return ret; } - tcf_bind_filter(tp, &prog->res, base); - tcf_exts_change(tp, &prog->exts, &exts); + if (tb[TCA_BPF_CLASSID]) { + prog->res.classid = nla_get_u32(tb[TCA_BPF_CLASSID]); + tcf_bind_filter(tp, &prog->res, base); + } + tcf_exts_change(tp, &prog->exts, &exts); return 0; } @@ -479,7 +477,8 @@ static int cls_bpf_dump(struct net *net, struct tcf_proto *tp, unsigned long fh, if (nest == NULL) goto nla_put_failure; - if (nla_put_u32(skb, TCA_BPF_CLASSID, prog->res.classid)) + if (prog->res.classid && + nla_put_u32(skb, TCA_BPF_CLASSID, prog->res.classid)) goto nla_put_failure; if (cls_bpf_is_ebpf(prog))