[PATCH bpf-next v8 03/11] bpf: Add eBPF program subtype and is_valid_subtype() verifier

From: MickaÃl SalaÃn
Date: Mon Feb 26 2018 - 19:46:12 EST

The goal of the program subtype is to be able to have different static
fine-grained verifications for a unique program type.

The struct bpf_verifier_ops gets a new optional function:
is_valid_subtype(). This new verifier is called at the beginning of the
eBPF program verification to check if the (optional) program subtype is
valid.

The struct bpf_prog_ops gets a new optional function: put_extra(). This
may be used to put extra data.

For now, only Landlock eBPF programs are using a program subtype (see
next commits) but this could be used by other program types in the
future.

Signed-off-by: MickaÃl SalaÃn <mic@xxxxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxxxxxx>
Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20160827205559.GA43880@xxxxxxxxxxxxxxxxxxxxxxx
---

Changes since v7:
* rename LANDLOCK_SUBTYPE_* to LANDLOCK_*
* move subtype in bpf_prog_aux and use only one bit for has_subtype
(suggested by Alexei Starovoitov)
* wrap the prog_subtype with a prog_extra to be able to reference kernel
pointers:
* add an optional put_extra() function to struct bpf_prog_ops to be
able to free the pointed data
* replace all the prog_subtype with prog_extra in the struct
bpf_verifier_ops functions
* remove the ABI field (requested by Alexei Starovoitov)
* rename subtype fields

Changes since v6:
* rename Landlock version to ABI to better reflect its purpose
* fix unsigned integer checks
* fix pointer cast
* constify pointers
* rebase

Changes since v5:
* use a prog_subtype pointer and make it future-proof
* add subtype test
* constify bpf_load_program()'s subtype argument
* cleanup subtype initialization
* rebase

Changes since v4:
* replace the "status" field with "version" (more generic)
* replace the "access" field with "ability" (less confusing)

Changes since v3:
* remove the "origin" field
* add an "option" field
* cleanup comments
---
include/linux/bpf.h | 17 ++++++-
include/uapi/linux/bpf.h | 11 +++++
kernel/bpf/cgroup.c | 6 ++-
kernel/bpf/core.c | 5 +-
kernel/bpf/syscall.c | 35 ++++++++++++-
kernel/bpf/verifier.c | 19 ++++++--
kernel/trace/bpf_trace.c | 15 ++++--
net/core/filter.c | 76 ++++++++++++++++++-----------
samples/bpf/bpf_load.c | 3 +-
samples/bpf/cookie_uid_helper_example.c | 2 +-
samples/bpf/fds_example.c | 2 +-
samples/bpf/sock_example.c | 3 +-
samples/bpf/test_cgrp2_attach.c | 2 +-
samples/bpf/test_cgrp2_attach2.c | 4 +-
samples/bpf/test_cgrp2_sock.c | 2 +-
tools/include/uapi/linux/bpf.h | 11 +++++
tools/lib/bpf/bpf.c | 15 ++++--
tools/lib/bpf/bpf.h | 8 +--
tools/lib/bpf/libbpf.c | 5 +-
tools/perf/tests/bpf.c | 2 +-
tools/testing/selftests/bpf/test_align.c | 2 +-
tools/testing/selftests/bpf/test_tag.c | 2 +-
tools/testing/selftests/bpf/test_verifier.c | 18 ++++++-
23 files changed, 200 insertions(+), 65 deletions(-)

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 66df387106de..377b2f3519f3 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -200,26 +200,38 @@ bpf_ctx_record_field_size(struct bpf_insn_access_aux *aux, u32 size)
aux->ctx_field_size = size;
}

+/* specific data per program type */
+struct bpf_prog_extra {
+ union bpf_prog_subtype subtype;
+ union {
+ struct bpf_prog *previous;
+ } landlock_hook;
+};
+
struct bpf_prog_ops {
int (*test_run)(struct bpf_prog *prog, const union bpf_attr *kattr,
union bpf_attr __user *uattr);
+ void (*put_extra)(struct bpf_prog_extra *prog_extra);
};

struct bpf_verifier_ops {
/* return eBPF function prototype for verification */
- const struct bpf_func_proto *(*get_func_proto)(enum bpf_func_id func_id);
+ const struct bpf_func_proto *(*get_func_proto)(enum bpf_func_id func_id,
+ const struct bpf_prog_extra *prog_extra);

/* return true if 'size' wide access at offset 'off' within bpf_context
* with 'type' (read or write) is allowed
*/
bool (*is_valid_access)(int off, int size, enum bpf_access_type type,
- struct bpf_insn_access_aux *info);
+ struct bpf_insn_access_aux *info,
+ const struct bpf_prog_extra *prog_extra);
int (*gen_prologue)(struct bpf_insn *insn, bool direct_write,
const struct bpf_prog *prog);
u32 (*convert_ctx_access)(enum bpf_access_type type,
const struct bpf_insn *src,
struct bpf_insn *dst,
struct bpf_prog *prog, u32 *target_size);
+ bool (*is_valid_subtype)(struct bpf_prog_extra *prog_extra);
};

struct bpf_prog_offload_ops {
@@ -264,6 +276,7 @@ struct bpf_prog_aux {
struct work_struct work;
struct rcu_head rcu;
};
+ struct bpf_prog_extra *extra;
};

struct bpf_array {
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index db6bdc375126..87885c92ca78 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -231,6 +231,15 @@ enum bpf_attach_type {
#define BPF_F_RDONLY (1U << 3)
#define BPF_F_WRONLY (1U << 4)

+union bpf_prog_subtype {
+ struct {
+ __u32 type; /* enum landlock_hook_type */
+ __aligned_u64 triggers; /* LANDLOCK_TRIGGER_* */
+ __aligned_u64 options; /* LANDLOCK_OPTION_* */
+ __u32 previous; /* chained program FD */
+ } landlock_hook;
+} __attribute__((aligned(8)));
+
union bpf_attr {
struct { /* anonymous struct used by BPF_MAP_CREATE command */
__u32 map_type; /* one of enum bpf_map_type */
@@ -270,6 +279,8 @@ union bpf_attr {
__u32 prog_flags;
char prog_name[BPF_OBJ_NAME_LEN];
__u32 prog_ifindex; /* ifindex of netdev to prep for */
+ __aligned_u64 prog_subtype; /* bpf_prog_subtype address */
+ __u32 prog_subtype_size;
};

struct { /* anonymous struct used by BPF_OBJ_* commands */
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
index c1c0b60d3f2f..77d6d25d2f50 100644
--- a/kernel/bpf/cgroup.c
+++ b/kernel/bpf/cgroup.c
@@ -545,7 +545,8 @@ int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor,
EXPORT_SYMBOL(__cgroup_bpf_check_dev_permission);

static const struct bpf_func_proto *
-cgroup_dev_func_proto(enum bpf_func_id func_id)
+cgroup_dev_func_proto(enum bpf_func_id func_id,
+ const struct bpf_prog_extra *prog_extra)
{
switch (func_id) {
case BPF_FUNC_map_lookup_elem:
@@ -566,7 +567,8 @@ cgroup_dev_func_proto(enum bpf_func_id func_id)

static bool cgroup_dev_is_valid_access(int off, int size,
enum bpf_access_type type,
- struct bpf_insn_access_aux *info)
+ struct bpf_insn_access_aux *info,
+ const struct bpf_prog_extra *prog_extra)
{
const int size_default = sizeof(__u32);

diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 29ca9208dcfa..e4567f7434af 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -142,7 +142,10 @@ struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,

void __bpf_prog_free(struct bpf_prog *fp)
{
- kfree(fp->aux);
+ if (fp->aux) {
+ kfree(fp->aux->extra);
+ kfree(fp->aux);
+ }
vfree(fp);
}

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index e24aa3241387..90d7de6d7393 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -992,6 +992,8 @@ static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
if (atomic_dec_and_test(&prog->aux->refcnt)) {
int i;

+ if (prog->aux->ops->put_extra && prog->aux->extra)
+ prog->aux->ops->put_extra(prog->aux->extra);
trace_bpf_prog_put_rcu(prog);
/* bpf_prog_free_id() must be called first */
bpf_prog_free_id(prog, do_idr_lock);
@@ -1168,7 +1170,7 @@ struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);

/* last field in 'union bpf_attr' used by this command */
-#define BPF_PROG_LOAD_LAST_FIELD prog_ifindex
+#define BPF_PROG_LOAD_LAST_FIELD prog_subtype_size

static int bpf_prog_load(union bpf_attr *attr)
{
@@ -1249,6 +1251,35 @@ static int bpf_prog_load(union bpf_attr *attr)
if (err)
goto free_prog;

+ /* copy eBPF program subtype from user space */
+ if (attr->prog_subtype) {
+ u32 size;
+
+ err = check_uarg_tail_zero(u64_to_user_ptr(attr->prog_subtype),
+ sizeof(prog->aux->extra->subtype),
+ attr->prog_subtype_size);
+ if (err)
+ goto free_prog;
+ size = min_t(u32, attr->prog_subtype_size,
+ sizeof(prog->aux->extra->subtype));
+
+ prog->aux->extra = kzalloc(sizeof(*prog->aux->extra),
+ GFP_KERNEL | GFP_USER);
+ if (!prog->aux->extra) {
+ err = -ENOMEM;
+ goto free_prog;
+ }
+ if (copy_from_user(&prog->aux->extra->subtype,
+ u64_to_user_ptr(attr->prog_subtype), size)
+ != 0) {
+ err = -EFAULT;
+ goto free_prog;
+ }
+ } else if (attr->prog_subtype_size != 0) {
+ err = -EINVAL;
+ goto free_prog;
+ }
+
/* run eBPF verifier */
err = bpf_check(&prog, attr);
if (err < 0)
@@ -1281,6 +1312,8 @@ static int bpf_prog_load(union bpf_attr *attr)
return err;

free_used_maps:
+ if (prog->aux->ops->put_extra && prog->aux->extra)
+ prog->aux->ops->put_extra(prog->aux->extra);
free_used_maps(prog->aux);
free_prog:
bpf_prog_uncharge_memlock(prog);
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 3c74b163eaeb..ed0905338bb6 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1310,7 +1310,8 @@ static int check_ctx_access(struct bpf_verifier_env *env, int insn_idx, int off,
};

if (env->ops->is_valid_access &&
- env->ops->is_valid_access(off, size, t, &info)) {
+ env->ops->is_valid_access(off, size, t, &info,
+ env->prog->aux->extra)) {
/* A non zero info.ctx_field_size indicates that this field is a
* candidate for later verifier transformation to load the whole
* field and then apply a mask when accessed with a narrower
@@ -2325,7 +2326,8 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
}

if (env->ops->get_func_proto)
- fn = env->ops->get_func_proto(func_id);
+ fn = env->ops->get_func_proto(func_id, env->prog->aux->extra);
+
if (!fn) {
verbose(env, "unknown func %s#%d\n", func_id_name(func_id),
func_id);
@@ -5546,7 +5548,7 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
insn = new_prog->insnsi + i + delta;
}
patch_call_imm:
- fn = env->ops->get_func_proto(insn->imm);
+ fn = env->ops->get_func_proto(insn->imm, prog->aux->extra);
/* all functions that have prototype and verifier allowed
* programs to call them, must be real in-kernel functions
*/
@@ -5633,6 +5635,17 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr)
if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS))
env->strict_alignment = true;

+ if (env->ops->is_valid_subtype) {
+ if (!env->ops->is_valid_subtype(env->prog->aux->extra)) {
+ ret = -EINVAL;
+ goto err_unlock;
+ }
+ } else if (env->prog->aux->extra) {
+ /* do not accept a subtype if the program does not handle it */
+ ret = -EINVAL;
+ goto err_unlock;
+ }
+
if (bpf_prog_is_dev_bound(env->prog->aux)) {
ret = bpf_prog_offload_verifier_prep(env);
if (ret)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index fc2838ac8b78..bb5ada28c0f6 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -568,7 +568,8 @@ static const struct bpf_func_proto *tracing_func_proto(enum bpf_func_id func_id)
}
}

-static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func_id)
+static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func_id,
+ const struct bpf_prog_extra *prog_extra)
{
switch (func_id) {
case BPF_FUNC_perf_event_output:
@@ -588,7 +589,8 @@ static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func

/* bpf+kprobe programs can access fields of 'struct pt_regs' */
static bool kprobe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
- struct bpf_insn_access_aux *info)
+ struct bpf_insn_access_aux *info,
+ const struct bpf_prog_extra *prog_extra)
{
if (off < 0 || off >= sizeof(struct pt_regs))
return false;
@@ -687,7 +689,8 @@ static const struct bpf_func_proto bpf_perf_prog_read_value_proto_tp = {
.arg3_type = ARG_CONST_SIZE,
};

-static const struct bpf_func_proto *tp_prog_func_proto(enum bpf_func_id func_id)
+static const struct bpf_func_proto *tp_prog_func_proto(enum bpf_func_id func_id,
+ const struct bpf_prog_extra *prog_extra)
{
switch (func_id) {
case BPF_FUNC_perf_event_output:
@@ -702,7 +705,8 @@ static const struct bpf_func_proto *tp_prog_func_proto(enum bpf_func_id func_id)
}

static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type,
- struct bpf_insn_access_aux *info)
+ struct bpf_insn_access_aux *info,
+ const struct bpf_prog_extra *prog_extra)
{
if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE)
return false;
@@ -724,7 +728,8 @@ const struct bpf_prog_ops tracepoint_prog_ops = {
};

static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
- struct bpf_insn_access_aux *info)
+ struct bpf_insn_access_aux *info,
+ const struct bpf_prog_extra *prog_extra)
{
const int size_sp = FIELD_SIZEOF(struct bpf_perf_event_data,
sample_period);
diff --git a/net/core/filter.c b/net/core/filter.c
index 08ab4c65a998..8c01140db592 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -3403,7 +3403,8 @@ static const struct bpf_func_proto bpf_sock_ops_cb_flags_set_proto = {
};

static const struct bpf_func_proto *
-bpf_base_func_proto(enum bpf_func_id func_id)
+bpf_base_func_proto(enum bpf_func_id func_id,
+ const struct bpf_prog_extra *prog_extra)
{
switch (func_id) {
case BPF_FUNC_map_lookup_elem:
@@ -3431,7 +3432,8 @@ bpf_base_func_proto(enum bpf_func_id func_id)
}

static const struct bpf_func_proto *
-sock_filter_func_proto(enum bpf_func_id func_id)
+sock_filter_func_proto(enum bpf_func_id func_id,
+ const struct bpf_prog_extra *prog_extra)
{
switch (func_id) {
/* inet and inet6 sockets are created in a process
@@ -3440,12 +3442,13 @@ sock_filter_func_proto(enum bpf_func_id func_id)
case BPF_FUNC_get_current_uid_gid:
return &bpf_get_current_uid_gid_proto;
default:
- return bpf_base_func_proto(func_id);
+ return bpf_base_func_proto(func_id, prog_extra);
}
}

static const struct bpf_func_proto *
-sk_filter_func_proto(enum bpf_func_id func_id)
+sk_filter_func_proto(enum bpf_func_id func_id,
+ const struct bpf_prog_extra *prog_extra)
{
switch (func_id) {
case BPF_FUNC_skb_load_bytes:
@@ -3455,12 +3458,13 @@ sk_filter_func_proto(enum bpf_func_id func_id)
case BPF_FUNC_get_socket_uid:
return &bpf_get_socket_uid_proto;
default:
- return bpf_base_func_proto(func_id);
+ return bpf_base_func_proto(func_id, prog_extra);
}
}

static const struct bpf_func_proto *
-tc_cls_act_func_proto(enum bpf_func_id func_id)
+tc_cls_act_func_proto(enum bpf_func_id func_id,
+ const struct bpf_prog_extra *prog_extra)
{
switch (func_id) {
case BPF_FUNC_skb_store_bytes:
@@ -3522,12 +3526,13 @@ tc_cls_act_func_proto(enum bpf_func_id func_id)
case BPF_FUNC_get_socket_uid:
return &bpf_get_socket_uid_proto;
default:
- return bpf_base_func_proto(func_id);
+ return bpf_base_func_proto(func_id, prog_extra);
}
}

static const struct bpf_func_proto *
-xdp_func_proto(enum bpf_func_id func_id)
+xdp_func_proto(enum bpf_func_id func_id,
+ const struct bpf_prog_extra *prog_extra)
{
switch (func_id) {
case BPF_FUNC_perf_event_output:
@@ -3545,12 +3550,13 @@ xdp_func_proto(enum bpf_func_id func_id)
case BPF_FUNC_redirect_map:
return &bpf_xdp_redirect_map_proto;
default:
- return bpf_base_func_proto(func_id);
+ return bpf_base_func_proto(func_id, prog_extra);
}
}

static const struct bpf_func_proto *
-lwt_inout_func_proto(enum bpf_func_id func_id)
+lwt_inout_func_proto(enum bpf_func_id func_id,
+ const struct bpf_prog_extra *prog_extra)
{
switch (func_id) {
case BPF_FUNC_skb_load_bytes:
@@ -3572,12 +3578,13 @@ lwt_inout_func_proto(enum bpf_func_id func_id)
case BPF_FUNC_skb_under_cgroup:
return &bpf_skb_under_cgroup_proto;
default:
- return bpf_base_func_proto(func_id);
+ return bpf_base_func_proto(func_id, prog_extra);
}
}

static const struct bpf_func_proto *
- sock_ops_func_proto(enum bpf_func_id func_id)
+ sock_ops_func_proto(enum bpf_func_id func_id,
+ const struct bpf_prog_extra *prog_extra)
{
switch (func_id) {
case BPF_FUNC_setsockopt:
@@ -3589,11 +3596,13 @@ static const struct bpf_func_proto *
case BPF_FUNC_sock_map_update:
return &bpf_sock_map_update_proto;
default:
- return bpf_base_func_proto(func_id);
+ return bpf_base_func_proto(func_id, prog_extra);
}
}

-static const struct bpf_func_proto *sk_skb_func_proto(enum bpf_func_id func_id)
+static const struct bpf_func_proto *
+sk_skb_func_proto(enum bpf_func_id func_id,
+ const struct bpf_prog_extra *prog_extra)
{
switch (func_id) {
case BPF_FUNC_skb_store_bytes:
@@ -3613,12 +3622,13 @@ static const struct bpf_func_proto *sk_skb_func_proto(enum bpf_func_id func_id)
case BPF_FUNC_sk_redirect_map:
return &bpf_sk_redirect_map_proto;
default:
- return bpf_base_func_proto(func_id);
+ return bpf_base_func_proto(func_id, prog_extra);
}
}

static const struct bpf_func_proto *
-lwt_xmit_func_proto(enum bpf_func_id func_id)
+lwt_xmit_func_proto(enum bpf_func_id func_id,
+ const struct bpf_prog_extra *prog_extra)
{
switch (func_id) {
case BPF_FUNC_skb_get_tunnel_key:
@@ -3648,12 +3658,13 @@ lwt_xmit_func_proto(enum bpf_func_id func_id)
case BPF_FUNC_set_hash_invalid:
return &bpf_set_hash_invalid_proto;
default:
- return lwt_inout_func_proto(func_id);
+ return lwt_inout_func_proto(func_id, prog_extra);
}
}

static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
- struct bpf_insn_access_aux *info)
+ struct bpf_insn_access_aux *info,
+ const struct bpf_prog_extra *prog_extra)
{
const int size_default = sizeof(__u32);

@@ -3696,7 +3707,8 @@ static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type

static bool sk_filter_is_valid_access(int off, int size,
enum bpf_access_type type,
- struct bpf_insn_access_aux *info)
+ struct bpf_insn_access_aux *info,
+ const struct bpf_prog_extra *prog_extra)
{
switch (off) {
case bpf_ctx_range(struct __sk_buff, tc_classid):
@@ -3716,12 +3728,13 @@ static bool sk_filter_is_valid_access(int off, int size,
}
}

- return bpf_skb_is_valid_access(off, size, type, info);
+ return bpf_skb_is_valid_access(off, size, type, info, prog_extra);
}

static bool lwt_is_valid_access(int off, int size,
enum bpf_access_type type,
- struct bpf_insn_access_aux *info)
+ struct bpf_insn_access_aux *info,
+ const struct bpf_prog_extra *prog_extra)
{
switch (off) {
case bpf_ctx_range(struct __sk_buff, tc_classid):
@@ -3750,12 +3763,13 @@ static bool lwt_is_valid_access(int off, int size,
break;
}

- return bpf_skb_is_valid_access(off, size, type, info);
+ return bpf_skb_is_valid_access(off, size, type, info, prog_extra);
}

static bool sock_filter_is_valid_access(int off, int size,
enum bpf_access_type type,
- struct bpf_insn_access_aux *info)
+ struct bpf_insn_access_aux *info,
+ const struct bpf_prog_extra *prog_extra)
{
if (type == BPF_WRITE) {
switch (off) {
@@ -3826,7 +3840,8 @@ static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,

static bool tc_cls_act_is_valid_access(int off, int size,
enum bpf_access_type type,
- struct bpf_insn_access_aux *info)
+ struct bpf_insn_access_aux *info,
+ const struct bpf_prog_extra *prog_extra)
{
if (type == BPF_WRITE) {
switch (off) {
@@ -3855,7 +3870,7 @@ static bool tc_cls_act_is_valid_access(int off, int size,
return false;
}

- return bpf_skb_is_valid_access(off, size, type, info);
+ return bpf_skb_is_valid_access(off, size, type, info, prog_extra);
}

static bool __is_valid_xdp_access(int off, int size)
@@ -3872,7 +3887,8 @@ static bool __is_valid_xdp_access(int off, int size)

static bool xdp_is_valid_access(int off, int size,
enum bpf_access_type type,
- struct bpf_insn_access_aux *info)
+ struct bpf_insn_access_aux *info,
+ const struct bpf_prog_extra *prog_extra)
{
if (type == BPF_WRITE)
return false;
@@ -3904,7 +3920,8 @@ EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);

static bool sock_ops_is_valid_access(int off, int size,
enum bpf_access_type type,
- struct bpf_insn_access_aux *info)
+ struct bpf_insn_access_aux *info,
+ const struct bpf_prog_extra *prog_extra)
{
const int size_default = sizeof(__u32);

@@ -3950,7 +3967,8 @@ static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,

static bool sk_skb_is_valid_access(int off, int size,
enum bpf_access_type type,
- struct bpf_insn_access_aux *info)
+ struct bpf_insn_access_aux *info,
+ const struct bpf_prog_extra *prog_extra)
{
switch (off) {
case bpf_ctx_range(struct __sk_buff, tc_classid):
@@ -3979,7 +3997,7 @@ static bool sk_skb_is_valid_access(int off, int size,
break;
}

- return bpf_skb_is_valid_access(off, size, type, info);
+ return bpf_skb_is_valid_access(off, size, type, info, prog_extra);
}

static u32 bpf_convert_ctx_access(enum bpf_access_type type,
diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c
index 69806d74fa53..5bb37db6054b 100644
--- a/samples/bpf/bpf_load.c
+++ b/samples/bpf/bpf_load.c
@@ -72,6 +72,7 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
char buf[256];
int fd, efd, err, id;
struct perf_event_attr attr = {};
+ union bpf_prog_subtype *st = NULL;

attr.type = PERF_TYPE_TRACEPOINT;
attr.sample_type = PERF_SAMPLE_RAW;
@@ -102,7 +103,7 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size)
}

fd = bpf_load_program(prog_type, prog, insns_cnt, license, kern_version,
- bpf_log_buf, BPF_LOG_BUF_SIZE);
+ bpf_log_buf, BPF_LOG_BUF_SIZE, st);
if (fd < 0) {
printf("bpf_load_program() err=%d\n%s", errno, bpf_log_buf);
return -1;
diff --git a/samples/bpf/cookie_uid_helper_example.c b/samples/bpf/cookie_uid_helper_example.c
index 9d751e209f31..df457c07d35d 100644
--- a/samples/bpf/cookie_uid_helper_example.c
+++ b/samples/bpf/cookie_uid_helper_example.c
@@ -159,7 +159,7 @@ static void prog_load(void)
};
prog_fd = bpf_load_program(BPF_PROG_TYPE_SOCKET_FILTER, prog,
ARRAY_SIZE(prog), "GPL", 0,
- log_buf, sizeof(log_buf));
+ log_buf, sizeof(log_buf), NULL);
if (prog_fd < 0)
error(1, errno, "failed to load prog\n%s\n", log_buf);
}
diff --git a/samples/bpf/fds_example.c b/samples/bpf/fds_example.c
index e29bd52ff9e8..0f4f5f6a9f9f 100644
--- a/samples/bpf/fds_example.c
+++ b/samples/bpf/fds_example.c
@@ -62,7 +62,7 @@ static int bpf_prog_create(const char *object)
} else {
return bpf_load_program(BPF_PROG_TYPE_SOCKET_FILTER,
insns, insns_cnt, "GPL", 0,
- bpf_log_buf, BPF_LOG_BUF_SIZE);
+ bpf_log_buf, BPF_LOG_BUF_SIZE, NULL);
}
}

diff --git a/samples/bpf/sock_example.c b/samples/bpf/sock_example.c
index 6fc6e193ef1b..3778f66deb76 100644
--- a/samples/bpf/sock_example.c
+++ b/samples/bpf/sock_example.c
@@ -60,7 +60,8 @@ static int test_sock(void)
size_t insns_cnt = sizeof(prog) / sizeof(struct bpf_insn);

prog_fd = bpf_load_program(BPF_PROG_TYPE_SOCKET_FILTER, prog, insns_cnt,
- "GPL", 0, bpf_log_buf, BPF_LOG_BUF_SIZE);
+ "GPL", 0, bpf_log_buf, BPF_LOG_BUF_SIZE,
+ NULL);
if (prog_fd < 0) {
printf("failed to load prog '%s'\n", strerror(errno));
goto cleanup;
diff --git a/samples/bpf/test_cgrp2_attach.c b/samples/bpf/test_cgrp2_attach.c
index 4bfcaf93fcf3..f8a91d2b7896 100644
--- a/samples/bpf/test_cgrp2_attach.c
+++ b/samples/bpf/test_cgrp2_attach.c
@@ -72,7 +72,7 @@ static int prog_load(int map_fd, int verdict)

return bpf_load_program(BPF_PROG_TYPE_CGROUP_SKB,
prog, insns_cnt, "GPL", 0,
- bpf_log_buf, BPF_LOG_BUF_SIZE);
+ bpf_log_buf, BPF_LOG_BUF_SIZE, NULL);
}

static int usage(const char *argv0)
diff --git a/samples/bpf/test_cgrp2_attach2.c b/samples/bpf/test_cgrp2_attach2.c
index 1af412ec6007..16023240ce5d 100644
--- a/samples/bpf/test_cgrp2_attach2.c
+++ b/samples/bpf/test_cgrp2_attach2.c
@@ -45,7 +45,7 @@ static int prog_load(int verdict)

ret = bpf_load_program(BPF_PROG_TYPE_CGROUP_SKB,
prog, insns_cnt, "GPL", 0,
- bpf_log_buf, BPF_LOG_BUF_SIZE);
+ bpf_log_buf, BPF_LOG_BUF_SIZE, NULL);

if (ret < 0) {
log_err("Loading program");
@@ -229,7 +229,7 @@ static int prog_load_cnt(int verdict, int val)

ret = bpf_load_program(BPF_PROG_TYPE_CGROUP_SKB,
prog, insns_cnt, "GPL", 0,
- bpf_log_buf, BPF_LOG_BUF_SIZE);
+ bpf_log_buf, BPF_LOG_BUF_SIZE, NULL);

if (ret < 0) {
log_err("Loading program");
diff --git a/samples/bpf/test_cgrp2_sock.c b/samples/bpf/test_cgrp2_sock.c
index e79594dd629b..b4b8d96f61e7 100644
--- a/samples/bpf/test_cgrp2_sock.c
+++ b/samples/bpf/test_cgrp2_sock.c
@@ -115,7 +115,7 @@ static int prog_load(__u32 idx, __u32 mark, __u32 prio)
insns_cnt /= sizeof(struct bpf_insn);

ret = bpf_load_program(BPF_PROG_TYPE_CGROUP_SOCK, prog, insns_cnt,
- "GPL", 0, bpf_log_buf, BPF_LOG_BUF_SIZE);
+ "GPL", 0, bpf_log_buf, BPF_LOG_BUF_SIZE, NULL);

free(prog);

diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index db6bdc375126..87885c92ca78 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -231,6 +231,15 @@ enum bpf_attach_type {
#define BPF_F_RDONLY (1U << 3)
#define BPF_F_WRONLY (1U << 4)

+union bpf_prog_subtype {
+ struct {
+ __u32 type; /* enum landlock_hook_type */
+ __aligned_u64 triggers; /* LANDLOCK_TRIGGER_* */
+ __aligned_u64 options; /* LANDLOCK_OPTION_* */
+ __u32 previous; /* chained program FD */
+ } landlock_hook;
+} __attribute__((aligned(8)));
+
union bpf_attr {
struct { /* anonymous struct used by BPF_MAP_CREATE command */
__u32 map_type; /* one of enum bpf_map_type */
@@ -270,6 +279,8 @@ union bpf_attr {
__u32 prog_flags;
char prog_name[BPF_OBJ_NAME_LEN];
__u32 prog_ifindex; /* ifindex of netdev to prep for */
+ __aligned_u64 prog_subtype; /* bpf_prog_subtype address */
+ __u32 prog_subtype_size;
};

struct { /* anonymous struct used by BPF_OBJ_* commands */
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 592a58a2b681..630060c71c5e 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -150,7 +150,8 @@ int bpf_load_program_name(enum bpf_prog_type type, const char *name,
const struct bpf_insn *insns,
size_t insns_cnt, const char *license,
__u32 kern_version, char *log_buf,
- size_t log_buf_sz)
+ size_t log_buf_sz,
+ const union bpf_prog_subtype *subtype)
{
int fd;
union bpf_attr attr;
@@ -166,6 +167,8 @@ int bpf_load_program_name(enum bpf_prog_type type, const char *name,
attr.log_level = 0;
attr.kern_version = kern_version;
memcpy(attr.prog_name, name, min(name_len, BPF_OBJ_NAME_LEN - 1));
+ attr.prog_subtype = ptr_to_u64(subtype);
+ attr.prog_subtype_size = subtype ? sizeof(*subtype) : 0;

fd = sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
if (fd >= 0 || !log_buf || !log_buf_sz)
@@ -182,16 +185,18 @@ int bpf_load_program_name(enum bpf_prog_type type, const char *name,
int bpf_load_program(enum bpf_prog_type type, const struct bpf_insn *insns,
size_t insns_cnt, const char *license,
__u32 kern_version, char *log_buf,
- size_t log_buf_sz)
+ size_t log_buf_sz, const union bpf_prog_subtype *subtype)
{
return bpf_load_program_name(type, NULL, insns, insns_cnt, license,
- kern_version, log_buf, log_buf_sz);
+ kern_version, log_buf, log_buf_sz,
+ subtype);
}

int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns,
size_t insns_cnt, int strict_alignment,
const char *license, __u32 kern_version,
- char *log_buf, size_t log_buf_sz, int log_level)
+ char *log_buf, size_t log_buf_sz, int log_level,
+ const union bpf_prog_subtype *subtype)
{
union bpf_attr attr;

@@ -205,6 +210,8 @@ int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns,
attr.log_level = log_level;
log_buf[0] = 0;
attr.kern_version = kern_version;
+ attr.prog_subtype = ptr_to_u64(subtype);
+ attr.prog_subtype_size = subtype ? sizeof(*subtype) : 0;
attr.prog_flags = strict_alignment ? BPF_F_STRICT_ALIGNMENT : 0;

return sys_bpf(BPF_PROG_LOAD, &attr, sizeof(attr));
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 8d18fb73d7fb..25f58da59df3 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -47,15 +47,17 @@ int bpf_load_program_name(enum bpf_prog_type type, const char *name,
const struct bpf_insn *insns,
size_t insns_cnt, const char *license,
__u32 kern_version, char *log_buf,
- size_t log_buf_sz);
+ size_t log_buf_sz,
+ const union bpf_prog_subtype *subtype);
int bpf_load_program(enum bpf_prog_type type, const struct bpf_insn *insns,
size_t insns_cnt, const char *license,
__u32 kern_version, char *log_buf,
- size_t log_buf_sz);
+ size_t log_buf_sz, const union bpf_prog_subtype *subtype);
int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns,
size_t insns_cnt, int strict_alignment,
const char *license, __u32 kern_version,
- char *log_buf, size_t log_buf_sz, int log_level);
+ char *log_buf, size_t log_buf_sz, int log_level,
+ const union bpf_prog_subtype *subtype);

int bpf_map_update_elem(int fd, const void *key, const void *value,
__u64 flags);
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 97073d649c1a..615860db6224 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -1175,7 +1175,8 @@ load_program(enum bpf_prog_type type, const char *name, struct bpf_insn *insns,
pr_warning("Alloc log buffer for bpf loader error, continue without log\n");

ret = bpf_load_program_name(type, name, insns, insns_cnt, license,
- kern_version, log_buf, BPF_LOG_BUF_SIZE);
+ kern_version, log_buf, BPF_LOG_BUF_SIZE,
+ NULL);

if (ret >= 0) {
*pfd = ret;
@@ -1202,7 +1203,7 @@ load_program(enum bpf_prog_type type, const char *name, struct bpf_insn *insns,

fd = bpf_load_program_name(BPF_PROG_TYPE_KPROBE, name,
insns, insns_cnt, license,
- kern_version, NULL, 0);
+ kern_version, NULL, 0, NULL);
if (fd >= 0) {
close(fd);
ret = -LIBBPF_ERRNO__PROGTYPE;
diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c
index e8399beca62b..2635de920a71 100644
--- a/tools/perf/tests/bpf.c
+++ b/tools/perf/tests/bpf.c
@@ -306,7 +306,7 @@ static int check_env(void)

err = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns,
sizeof(insns) / sizeof(insns[0]),
- license, kver_int, NULL, 0);
+ license, kver_int, NULL, 0, NULL);
if (err < 0) {
pr_err("Missing basic BPF support, skip this test: %s\n",
strerror(errno));
diff --git a/tools/testing/selftests/bpf/test_align.c b/tools/testing/selftests/bpf/test_align.c
index ff8bd7e3e50c..ed638ce9932e 100644
--- a/tools/testing/selftests/bpf/test_align.c
+++ b/tools/testing/selftests/bpf/test_align.c
@@ -625,7 +625,7 @@ static int do_test_single(struct bpf_align_test *test)
prog_len = probe_filter_length(prog);
fd_prog = bpf_verify_program(prog_type ? : BPF_PROG_TYPE_SOCKET_FILTER,
prog, prog_len, 1, "GPL", 0,
- bpf_vlog, sizeof(bpf_vlog), 2);
+ bpf_vlog, sizeof(bpf_vlog), 2, NULL);
if (fd_prog < 0 && test->result != REJECT) {
printf("Failed to load program.\n");
printf("%s", bpf_vlog);
diff --git a/tools/testing/selftests/bpf/test_tag.c b/tools/testing/selftests/bpf/test_tag.c
index 8b201895c569..0b58e746af0c 100644
--- a/tools/testing/selftests/bpf/test_tag.c
+++ b/tools/testing/selftests/bpf/test_tag.c
@@ -58,7 +58,7 @@ static int bpf_try_load_prog(int insns, int fd_map,

bpf_filler(insns, fd_map);
fd_prog = bpf_load_program(BPF_PROG_TYPE_SCHED_CLS, prog, insns, "", 0,
- NULL, 0);
+ NULL, 0, NULL);
assert(fd_prog > 0);
if (fd_map > 0)
bpf_filler(insns, 0);
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index c987d3a2426f..3c24a5a7bafc 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -77,6 +77,8 @@ struct bpf_test {
} result, result_unpriv;
enum bpf_prog_type prog_type;
uint8_t flags;
+ bool has_prog_subtype;
+ union bpf_prog_subtype prog_subtype;
};

/* Note we want this to be 64 bit aligned so that the end of our array is
@@ -11228,7 +11230,16 @@ static struct bpf_test tests[] = {
.result = ACCEPT,
.retval = 2,
},
-
+ {
+ "superfluous subtype",
+ .insns = {
+ BPF_MOV32_IMM(BPF_REG_0, 0),
+ BPF_EXIT_INSN(),
+ },
+ .errstr = "",
+ .result = REJECT,
+ .has_prog_subtype = true,
+ },
};

static int probe_filter_length(const struct bpf_insn *fp)
@@ -11346,6 +11357,8 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
const char *expected_err;
uint32_t retval;
int i, err;
+ union bpf_prog_subtype *prog_subtype =
+ test->has_prog_subtype ? &test->prog_subtype : NULL;

for (i = 0; i < MAX_NR_MAPS; i++)
map_fds[i] = -1;
@@ -11354,7 +11367,8 @@ static void do_test_single(struct bpf_test *test, bool unpriv,

fd_prog = bpf_verify_program(prog_type ? : BPF_PROG_TYPE_SOCKET_FILTER,
prog, prog_len, test->flags & F_LOAD_WITH_STRICT_ALIGNMENT,
- "GPL", 0, bpf_vlog, sizeof(bpf_vlog), 1);
+ "GPL", 0, bpf_vlog, sizeof(bpf_vlog), 1,
+ prog_subtype);

expected_ret = unpriv && test->result_unpriv != UNDEF ?
test->result_unpriv : test->result;
--
2.16.2