diff options
| author | Cong Wang <xiyou.wangcong@gmail.com> | 2020-01-23 16:26:18 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-01-27 10:51:43 +0100 |
| commit | 2e24cd755552350b94a7617617c6877b8cbcb701 (patch) | |
| tree | afc648bcd17647501ff27e920feaebfac8c23958 /net/sched/cls_bpf.c | |
| parent | 16b25d1a968e683eeef7523a4bbc4c8fd63aeedc (diff) | |
net_sched: fix ops->bind_class() implementations
The current implementations of ops->bind_class() are merely
searching for classid and updating class in the struct tcf_result,
without invoking either of cl_ops->bind_tcf() or
cl_ops->unbind_tcf(). This breaks the design of them as qdisc's
like cbq use them to count filters too. This is why syzbot triggered
the warning in cbq_destroy_class().
In order to fix this, we have to call cl_ops->bind_tcf() and
cl_ops->unbind_tcf() like the filter binding path. This patch does
so by refactoring out two helper functions __tcf_bind_filter()
and __tcf_unbind_filter(), which are lockless and accept a Qdisc
pointer, then teaching each implementation to call them correctly.
Note, we merely pass the Qdisc pointer as an opaque pointer to
each filter, they only need to pass it down to the helper
functions without understanding it at all.
Fixes: 07d79fc7d94e ("net_sched: add reverse binding for tc class")
Reported-and-tested-by: syzbot+0a0596220218fcb603a8@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+63bdb6006961d8c917c6@syzkaller.appspotmail.com
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/sched/cls_bpf.c')
| -rw-r--r-- | net/sched/cls_bpf.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/net/sched/cls_bpf.c b/net/sched/cls_bpf.c index 8229ed4a67be..6e3e63db0e01 100644 --- a/net/sched/cls_bpf.c +++ b/net/sched/cls_bpf.c @@ -631,12 +631,17 @@ nla_put_failure: return -1; } -static void cls_bpf_bind_class(void *fh, u32 classid, unsigned long cl) +static void cls_bpf_bind_class(void *fh, u32 classid, unsigned long cl, + void *q, unsigned long base) { struct cls_bpf_prog *prog = fh; - if (prog && prog->res.classid == classid) - prog->res.class = cl; + if (prog && prog->res.classid == classid) { + if (cl) + __tcf_bind_filter(q, &prog->res, base); + else + __tcf_unbind_filter(q, &prog->res); + } } static void cls_bpf_walk(struct tcf_proto *tp, struct tcf_walker *arg, |