linux-stable/include/linux/bpf-netns.h
Lorenz Bauer 4ac2add659 bpf: flow_dissector: Check value of unused flags to BPF_PROG_DETACH
Using BPF_PROG_DETACH on a flow dissector program supports neither
attach_flags nor attach_bpf_fd. Yet no value is enforced for them.

Enforce that attach_flags are zero, and require the current program
to be passed via attach_bpf_fd. This allows us to remove the check
for CAP_SYS_ADMIN, since userspace can now no longer remove
arbitrary flow dissector programs.

Fixes: b27f7bb590 ("flow_dissector: Move out netns_bpf prog callbacks")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-3-lmb@cloudflare.com
2020-06-30 10:46:38 -07:00

65 lines
1.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _BPF_NETNS_H
#define _BPF_NETNS_H
#include <linux/mutex.h>
#include <uapi/linux/bpf.h>
enum netns_bpf_attach_type {
NETNS_BPF_INVALID = -1,
NETNS_BPF_FLOW_DISSECTOR = 0,
MAX_NETNS_BPF_ATTACH_TYPE
};
static inline enum netns_bpf_attach_type
to_netns_bpf_attach_type(enum bpf_attach_type attach_type)
{
switch (attach_type) {
case BPF_FLOW_DISSECTOR:
return NETNS_BPF_FLOW_DISSECTOR;
default:
return NETNS_BPF_INVALID;
}
}
/* Protects updates to netns_bpf */
extern struct mutex netns_bpf_mutex;
union bpf_attr;
struct bpf_prog;
#ifdef CONFIG_NET
int netns_bpf_prog_query(const union bpf_attr *attr,
union bpf_attr __user *uattr);
int netns_bpf_prog_attach(const union bpf_attr *attr,
struct bpf_prog *prog);
int netns_bpf_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype);
int netns_bpf_link_create(const union bpf_attr *attr,
struct bpf_prog *prog);
#else
static inline int netns_bpf_prog_query(const union bpf_attr *attr,
union bpf_attr __user *uattr)
{
return -EOPNOTSUPP;
}
static inline int netns_bpf_prog_attach(const union bpf_attr *attr,
struct bpf_prog *prog)
{
return -EOPNOTSUPP;
}
static inline int netns_bpf_prog_detach(const union bpf_attr *attr,
enum bpf_prog_type ptype)
{
return -EOPNOTSUPP;
}
static inline int netns_bpf_link_create(const union bpf_attr *attr,
struct bpf_prog *prog)
{
return -EOPNOTSUPP;
}
#endif
#endif /* _BPF_NETNS_H */