diff options
| author | Daniel Borkmann <daniel@iogearbox.net> | 2015-09-02 14:00:36 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-09-02 11:29:29 -0700 |
| commit | b382c08656000c12a146723a153b85b13a855b49 (patch) | |
| tree | 1a9404a05caebe9bebf9404027d580264be29ee7 | |
| parent | 20a17bf6c04e3eca8824c930ecc55ab832558e3b (diff) | |
sock, diag: fix panic in sock_diag_put_filterinfo
diag socket's sock_diag_put_filterinfo() dumps classic BPF programs
upon request to user space (ss -0 -b). However, native eBPF programs
attached to sockets (SO_ATTACH_BPF) cannot be dumped with this method:
Their orig_prog is always NULL. However, sock_diag_put_filterinfo()
unconditionally tries to access its filter length resp. wants to copy
the filter insns from there. Internal cBPF to eBPF transformations
attached to sockets don't have this issue, as orig_prog state is kept.
It's currently only used by packet sockets. If we would want to add
native eBPF support in the future, this needs to be done through
a different attribute than PACKET_DIAG_FILTER to not confuse possible
user space disassemblers that work on diag data.
Fixes: 89aa075832b0 ("net: sock: allow eBPF programs to be attached to sockets")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/core/sock_diag.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/core/sock_diag.c b/net/core/sock_diag.c index d79866c5f8bc..817622f3dbb7 100644 --- a/net/core/sock_diag.c +++ b/net/core/sock_diag.c @@ -90,6 +90,9 @@ int sock_diag_put_filterinfo(bool may_report_filterinfo, struct sock *sk, goto out; fprog = filter->prog->orig_prog; + if (!fprog) + goto out; + flen = bpf_classic_proglen(fprog); attr = nla_reserve(skb, attrtype, flen); |