Skip to content

L
linux
Switch branch/tag
  1. 20 Mar, 2015 2 commits
    • Daniel Borkmann's avatar
      net: cls_bpf: fix auto generation of per list handles · d817b892
      Daniel Borkmann authored 
      commit 3f2ab135 upstream.

When creating a bpf classifier in tc with priority collisions and
invoking automatic unique handle assignment, cls_bpf_grab_new_handle()
will return a wrong handle id which in fact is non-unique. Usually
altering of specific filters is being addressed over major id, but
in case of collisions we result in a filter chain, where handle ids
address individual cls_bpf_progs inside the classifier.

Issue is, in cls_bpf_grab_new_handle() we probe for head->hgen handle
in cls_bpf_get() and in case we found a free handle, we're supposed
to use exactly head->hgen. In case of insufficient numbers of handles,
we bail out later as handle id 0 is not allowed.

Fixes: 7d1d65cb ("net: sched: cls_bpf: add BPF-based classifier")
Signed-off-by: default avatarDaniel Borkmann <dborkman@redhat.com>
Acked-by: default avatarJiri Pirko <jiri@resnulli.us>
Acked-by: default avatarAlexei Starovoitov <ast@plumgrid.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarLuis Henriques <luis.henriques@canonical.com>
      d817b892
    • Daniel Borkmann's avatar
      net: cls_bpf: fix size mismatch on filter preparation · 709178a6
      Daniel Borkmann authored 
      commit 7913ecf6 upstream.

In cls_bpf_modify_existing(), we read out the number of filter blocks,
do some sanity checks, allocate a block on that size, and copy over the
BPF instruction blob from user space, then pass everything through the
classic BPF checker prior to installation of the classifier.

We should reject mismatches here, there are 2 scenarios: the number of
filter blocks could be smaller than the provided instruction blob, so
we do a partial copy of the BPF program, and thus the instructions will
either be rejected from the verifier or a valid BPF program will be run;
in the other case, we'll end up copying more than we're supposed to,
and most likely the trailing garbage will be rejected by the verifier
as well (i.e. we need to fit instruction pattern, ret {A,K} needs to be
last instruction, load/stores must be correct, etc); in case not, we
would leak memory when dumping back instruction patterns. The code should
have only used nla_len() as Dave noted to avoid this from the beginning.
Anyway, lets fix it by rejecting such load attempts.

Fixes: 7d1d65cb ("net: sched: cls_bpf: add BPF-based classifier")
Signed-off-by: default avatarDaniel Borkmann <dborkman@redhat.com>
Acked-by: default avatarJiri Pirko <jiri@resnulli.us>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarLuis Henriques <luis.henriques@canonical.com>
      709178a6
  3. 18 Mar, 2015 38 commits
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7