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2357672c54
linux/net/bpf/test_run.c
Kumar Kartikeya Dwivedi 2357672c54 bpf: Introduce BPF support for kernel module function calls 
This change adds support on the kernel side to allow for BPF programs to
call kernel module functions. Userspace will prepare an array of module
BTF fds that is passed in during BPF_PROG_LOAD using fd_array parameter.
In the kernel, the module BTFs are placed in the auxilliary struct for
bpf_prog, and loaded as needed.

The verifier then uses insn->off to index into the fd_array. insn->off
0 is reserved for vmlinux BTF (for backwards compat), so userspace must
use an fd_array index > 0 for module kfunc support. kfunc_btf_tab is
sorted based on offset in an array, and each offset corresponds to one
descriptor, with a max limit up to 256 such module BTFs.

We also change existing kfunc_tab to distinguish each element based on
imm, off pair as each such call will now be distinct.

Another change is to check_kfunc_call callback, which now include a
struct module * pointer, this is to be used in later patch such that the
kfunc_id and module pointer are matched for dynamically registered BTF
sets from loadable modules, so that same kfunc_id in two modules doesn't
lead to check_kfunc_call succeeding. For the duration of the
check_kfunc_call, the reference to struct module exists, as it returns
the pointer stored in kfunc_btf_tab.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211002011757.311265-2-memxor@gmail.com
2021-10-05 17:07:41 -07:00

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// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2017 Facebook
*/
#include <linux/bpf.h>
#include <linux/btf_ids.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/etherdevice.h>
#include <linux/filter.h>
#include <linux/rcupdate_trace.h>
#include <linux/sched/signal.h>
#include <net/bpf_sk_storage.h>
#include <net/sock.h>
#include <net/tcp.h>
#include <net/net_namespace.h>
#include <linux/error-injection.h>
#include <linux/smp.h>
#include <linux/sock_diag.h>
#include <net/xdp.h>
#define CREATE_TRACE_POINTS
#include <trace/events/bpf_test_run.h>
struct bpf_test_timer {
enum { NO_PREEMPT, NO_MIGRATE } mode;
u32 i;
u64 time_start, time_spent;
};
static void bpf_test_timer_enter(struct bpf_test_timer *t)
__acquires(rcu)
{
rcu_read_lock();
if (t->mode == NO_PREEMPT)
preempt_disable();
else
migrate_disable();
t->time_start = ktime_get_ns();
}
static void bpf_test_timer_leave(struct bpf_test_timer *t)
__releases(rcu)
{
t->time_start = 0;
if (t->mode == NO_PREEMPT)
preempt_enable();
else
migrate_enable();
rcu_read_unlock();
}
static bool bpf_test_timer_continue(struct bpf_test_timer *t, u32 repeat, int *err, u32 *duration)
__must_hold(rcu)
{
t->i++;
if (t->i >= repeat) {
/* We're done. */
t->time_spent += ktime_get_ns() - t->time_start;
do_div(t->time_spent, t->i);
*duration = t->time_spent > U32_MAX ? U32_MAX : (u32)t->time_spent;
*err = 0;
goto reset;
}
if (signal_pending(current)) {
/* During iteration: we've been cancelled, abort. */
*err = -EINTR;
goto reset;
}
if (need_resched()) {
/* During iteration: we need to reschedule between runs. */
t->time_spent += ktime_get_ns() - t->time_start;
bpf_test_timer_leave(t);
cond_resched();
bpf_test_timer_enter(t);
}
/* Do another round. */
return true;
reset:
t->i = 0;
return false;
}
static int bpf_test_run(struct bpf_prog *prog, void *ctx, u32 repeat,
u32 *retval, u32 *time, bool xdp)
{
struct bpf_prog_array_item item = {.prog = prog};
struct bpf_run_ctx *old_ctx;
struct bpf_cg_run_ctx run_ctx;
struct bpf_test_timer t = { NO_MIGRATE };
enum bpf_cgroup_storage_type stype;
int ret;
for_each_cgroup_storage_type(stype) {
item.cgroup_storage[stype] = bpf_cgroup_storage_alloc(prog, stype);
if (IS_ERR(item.cgroup_storage[stype])) {
item.cgroup_storage[stype] = NULL;
for_each_cgroup_storage_type(stype)
bpf_cgroup_storage_free(item.cgroup_storage[stype]);
return -ENOMEM;
}
}
if (!repeat)
repeat = 1;
bpf_test_timer_enter(&t);
old_ctx = bpf_set_run_ctx(&run_ctx.run_ctx);
do {
run_ctx.prog_item = &item;
if (xdp)
*retval = bpf_prog_run_xdp(prog, ctx);
else
*retval = bpf_prog_run(prog, ctx);
} while (bpf_test_timer_continue(&t, repeat, &ret, time));
bpf_reset_run_ctx(old_ctx);
bpf_test_timer_leave(&t);
for_each_cgroup_storage_type(stype)
bpf_cgroup_storage_free(item.cgroup_storage[stype]);
return ret;
}
static int bpf_test_finish(const union bpf_attr *kattr,
union bpf_attr __user *uattr, const void *data,
u32 size, u32 retval, u32 duration)
{
void __user *data_out = u64_to_user_ptr(kattr->test.data_out);
int err = -EFAULT;
u32 copy_size = size;
/* Clamp copy if the user has provided a size hint, but copy the full
* buffer if not to retain old behaviour.
*/
if (kattr->test.data_size_out &&
copy_size > kattr->test.data_size_out) {
copy_size = kattr->test.data_size_out;
err = -ENOSPC;
}
if (data_out && copy_to_user(data_out, data, copy_size))
goto out;
if (copy_to_user(&uattr->test.data_size_out, &size, sizeof(size)))
goto out;
if (copy_to_user(&uattr->test.retval, &retval, sizeof(retval)))
goto out;
if (copy_to_user(&uattr->test.duration, &duration, sizeof(duration)))
goto out;
if (err != -ENOSPC)
err = 0;
out:
trace_bpf_test_finish(&err);
return err;
}
/* Integer types of various sizes and pointer combinations cover variety of
* architecture dependent calling conventions. 7+ can be supported in the
* future.
*/
__diag_push();
__diag_ignore(GCC, 8, "-Wmissing-prototypes",
"Global functions as their definitions will be in vmlinux BTF");
int noinline bpf_fentry_test1(int a)
{
return a + 1;
}
int noinline bpf_fentry_test2(int a, u64 b)
{
return a + b;
}
int noinline bpf_fentry_test3(char a, int b, u64 c)
{
return a + b + c;
}
int noinline bpf_fentry_test4(void *a, char b, int c, u64 d)
{
return (long)a + b + c + d;
}
int noinline bpf_fentry_test5(u64 a, void *b, short c, int d, u64 e)
{
return a + (long)b + c + d + e;
}
int noinline bpf_fentry_test6(u64 a, void *b, short c, int d, void *e, u64 f)
{
return a + (long)b + c + d + (long)e + f;
}
struct bpf_fentry_test_t {
struct bpf_fentry_test_t *a;
};
int noinline bpf_fentry_test7(struct bpf_fentry_test_t *arg)
{
return (long)arg;
}
int noinline bpf_fentry_test8(struct bpf_fentry_test_t *arg)
{
return (long)arg->a;
}
int noinline bpf_modify_return_test(int a, int *b)
{
*b += 1;
return a + *b;
}
u64 noinline bpf_kfunc_call_test1(struct sock *sk, u32 a, u64 b, u32 c, u64 d)
{
return a + b + c + d;
}
int noinline bpf_kfunc_call_test2(struct sock *sk, u32 a, u32 b)
{
return a + b;
}
struct sock * noinline bpf_kfunc_call_test3(struct sock *sk)
{
return sk;
}
__diag_pop();
ALLOW_ERROR_INJECTION(bpf_modify_return_test, ERRNO);
BTF_SET_START(test_sk_kfunc_ids)
BTF_ID(func, bpf_kfunc_call_test1)
BTF_ID(func, bpf_kfunc_call_test2)
BTF_ID(func, bpf_kfunc_call_test3)
BTF_SET_END(test_sk_kfunc_ids)
bool bpf_prog_test_check_kfunc_call(u32 kfunc_id, struct module *owner)
{
return btf_id_set_contains(&test_sk_kfunc_ids, kfunc_id);
}
static void *bpf_test_init(const union bpf_attr *kattr, u32 size,
u32 headroom, u32 tailroom)
{
void __user *data_in = u64_to_user_ptr(kattr->test.data_in);
u32 user_size = kattr->test.data_size_in;
void *data;
if (size < ETH_HLEN || size > PAGE_SIZE - headroom - tailroom)
return ERR_PTR(-EINVAL);
if (user_size > size)
return ERR_PTR(-EMSGSIZE);
data = kzalloc(size + headroom + tailroom, GFP_USER);
if (!data)
return ERR_PTR(-ENOMEM);
if (copy_from_user(data + headroom, data_in, user_size)) {
kfree(data);
return ERR_PTR(-EFAULT);
}
return data;
}
int bpf_prog_test_run_tracing(struct bpf_prog *prog,
const union bpf_attr *kattr,
union bpf_attr __user *uattr)
{
struct bpf_fentry_test_t arg = {};
u16 side_effect = 0, ret = 0;
int b = 2, err = -EFAULT;
u32 retval = 0;
if (kattr->test.flags || kattr->test.cpu)
return -EINVAL;
switch (prog->expected_attach_type) {
case BPF_TRACE_FENTRY:
case BPF_TRACE_FEXIT:
if (bpf_fentry_test1(1) != 2 ||
bpf_fentry_test2(2, 3) != 5 ||
bpf_fentry_test3(4, 5, 6) != 15 ||
bpf_fentry_test4((void *)7, 8, 9, 10) != 34 ||
bpf_fentry_test5(11, (void *)12, 13, 14, 15) != 65 ||
bpf_fentry_test6(16, (void *)17, 18, 19, (void *)20, 21) != 111 ||
bpf_fentry_test7((struct bpf_fentry_test_t *)0) != 0 ||
bpf_fentry_test8(&arg) != 0)
goto out;
break;
case BPF_MODIFY_RETURN:
ret = bpf_modify_return_test(1, &b);
if (b != 2)
side_effect = 1;
break;
default:
goto out;
}
retval = ((u32)side_effect << 16) | ret;
if (copy_to_user(&uattr->test.retval, &retval, sizeof(retval)))
goto out;
err = 0;
out:
trace_bpf_test_finish(&err);
return err;
}
struct bpf_raw_tp_test_run_info {
struct bpf_prog *prog;
void *ctx;
u32 retval;
};
static void
__bpf_prog_test_run_raw_tp(void *data)
{
struct bpf_raw_tp_test_run_info *info = data;
rcu_read_lock();
info->retval = bpf_prog_run(info->prog, info->ctx);
rcu_read_unlock();
}
int bpf_prog_test_run_raw_tp(struct bpf_prog *prog,
const union bpf_attr *kattr,
union bpf_attr __user *uattr)
{
void __user *ctx_in = u64_to_user_ptr(kattr->test.ctx_in);
__u32 ctx_size_in = kattr->test.ctx_size_in;
struct bpf_raw_tp_test_run_info info;
int cpu = kattr->test.cpu, err = 0;
int current_cpu;
/* doesn't support data_in/out, ctx_out, duration, or repeat */
if (kattr->test.data_in || kattr->test.data_out ||
kattr->test.ctx_out || kattr->test.duration ||
kattr->test.repeat)
return -EINVAL;
if (ctx_size_in < prog->aux->max_ctx_offset ||
ctx_size_in > MAX_BPF_FUNC_ARGS * sizeof(u64))
return -EINVAL;
if ((kattr->test.flags & BPF_F_TEST_RUN_ON_CPU) == 0 && cpu != 0)
return -EINVAL;
if (ctx_size_in) {
info.ctx = kzalloc(ctx_size_in, GFP_USER);
if (!info.ctx)
return -ENOMEM;
if (copy_from_user(info.ctx, ctx_in, ctx_size_in)) {
err = -EFAULT;
goto out;
}
} else {
info.ctx = NULL;
}
info.prog = prog;
current_cpu = get_cpu();
if ((kattr->test.flags & BPF_F_TEST_RUN_ON_CPU) == 0 ||
cpu == current_cpu) {
__bpf_prog_test_run_raw_tp(&info);
} else if (cpu >= nr_cpu_ids || !cpu_online(cpu)) {
/* smp_call_function_single() also checks cpu_online()
* after csd_lock(). However, since cpu is from user
* space, let's do an extra quick check to filter out
* invalid value before smp_call_function_single().
*/
err = -ENXIO;
} else {
err = smp_call_function_single(cpu, __bpf_prog_test_run_raw_tp,
&info, 1);
}
put_cpu();
if (!err &&
copy_to_user(&uattr->test.retval, &info.retval, sizeof(u32)))
err = -EFAULT;
out:
kfree(info.ctx);
return err;
}
static void *bpf_ctx_init(const union bpf_attr *kattr, u32 max_size)
{
void __user *data_in = u64_to_user_ptr(kattr->test.ctx_in);
void __user *data_out = u64_to_user_ptr(kattr->test.ctx_out);
u32 size = kattr->test.ctx_size_in;
void *data;
int err;
if (!data_in && !data_out)
return NULL;
data = kzalloc(max_size, GFP_USER);
if (!data)
return ERR_PTR(-ENOMEM);
if (data_in) {
err = bpf_check_uarg_tail_zero(USER_BPFPTR(data_in), max_size, size);
if (err) {
kfree(data);
return ERR_PTR(err);
}
size = min_t(u32, max_size, size);
if (copy_from_user(data, data_in, size)) {
kfree(data);
return ERR_PTR(-EFAULT);
}
}
return data;
}
static int bpf_ctx_finish(const union bpf_attr *kattr,
union bpf_attr __user *uattr, const void *data,
u32 size)
{
void __user *data_out = u64_to_user_ptr(kattr->test.ctx_out);
int err = -EFAULT;
u32 copy_size = size;
if (!data || !data_out)
return 0;
if (copy_size > kattr->test.ctx_size_out) {
copy_size = kattr->test.ctx_size_out;
err = -ENOSPC;
}
if (copy_to_user(data_out, data, copy_size))
goto out;
if (copy_to_user(&uattr->test.ctx_size_out, &size, sizeof(size)))
goto out;
if (err != -ENOSPC)
err = 0;
out:
return err;
}
/**
* range_is_zero - test whether buffer is initialized
* @buf: buffer to check
* @from: check from this position
* @to: check up until (excluding) this position
*
* This function returns true if the there is a non-zero byte
* in the buf in the range [from,to).
*/
static inline bool range_is_zero(void *buf, size_t from, size_t to)
{
return !memchr_inv((u8 *)buf + from, 0, to - from);
}
static int convert___skb_to_skb(struct sk_buff *skb, struct __sk_buff *__skb)
{
struct qdisc_skb_cb *cb = (struct qdisc_skb_cb *)skb->cb;
if (!__skb)
return 0;
/* make sure the fields we don't use are zeroed */
if (!range_is_zero(__skb, 0, offsetof(struct __sk_buff, mark)))
return -EINVAL;
/* mark is allowed */
if (!range_is_zero(__skb, offsetofend(struct __sk_buff, mark),
offsetof(struct __sk_buff, priority)))
return -EINVAL;
/* priority is allowed */
/* ingress_ifindex is allowed */
/* ifindex is allowed */
if (!range_is_zero(__skb, offsetofend(struct __sk_buff, ifindex),
offsetof(struct __sk_buff, cb)))
return -EINVAL;
/* cb is allowed */
if (!range_is_zero(__skb, offsetofend(struct __sk_buff, cb),
offsetof(struct __sk_buff, tstamp)))
return -EINVAL;
/* tstamp is allowed */
/* wire_len is allowed */
/* gso_segs is allowed */
if (!range_is_zero(__skb, offsetofend(struct __sk_buff, gso_segs),
offsetof(struct __sk_buff, gso_size)))
return -EINVAL;
/* gso_size is allowed */
if (!range_is_zero(__skb, offsetofend(struct __sk_buff, gso_size),
offsetof(struct __sk_buff, hwtstamp)))
return -EINVAL;
/* hwtstamp is allowed */
if (!range_is_zero(__skb, offsetofend(struct __sk_buff, hwtstamp),
sizeof(struct __sk_buff)))
return -EINVAL;
skb->mark = __skb->mark;
skb->priority = __skb->priority;
skb->skb_iif = __skb->ingress_ifindex;
skb->tstamp = __skb->tstamp;
memcpy(&cb->data, __skb->cb, QDISC_CB_PRIV_LEN);
if (__skb->wire_len == 0) {
cb->pkt_len = skb->len;
} else {
if (__skb->wire_len < skb->len ||
__skb->wire_len > GSO_MAX_SIZE)
return -EINVAL;
cb->pkt_len = __skb->wire_len;
}
if (__skb->gso_segs > GSO_MAX_SEGS)
return -EINVAL;
skb_shinfo(skb)->gso_segs = __skb->gso_segs;
skb_shinfo(skb)->gso_size = __skb->gso_size;
skb_shinfo(skb)->hwtstamps.hwtstamp = __skb->hwtstamp;
return 0;
}
static void convert_skb_to___skb(struct sk_buff *skb, struct __sk_buff *__skb)
{
struct qdisc_skb_cb *cb = (struct qdisc_skb_cb *)skb->cb;
if (!__skb)
return;
__skb->mark = skb->mark;
__skb->priority = skb->priority;
__skb->ingress_ifindex = skb->skb_iif;
__skb->ifindex = skb->dev->ifindex;
__skb->tstamp = skb->tstamp;
memcpy(__skb->cb, &cb->data, QDISC_CB_PRIV_LEN);
__skb->wire_len = cb->pkt_len;
__skb->gso_segs = skb_shinfo(skb)->gso_segs;
__skb->hwtstamp = skb_shinfo(skb)->hwtstamps.hwtstamp;
}
static struct proto bpf_dummy_proto = {
.name = "bpf_dummy",
.owner = THIS_MODULE,
.obj_size = sizeof(struct sock),
};
int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
union bpf_attr __user *uattr)
{
bool is_l2 = false, is_direct_pkt_access = false;
struct net *net = current->nsproxy->net_ns;
struct net_device *dev = net->loopback_dev;
u32 size = kattr->test.data_size_in;
u32 repeat = kattr->test.repeat;
struct __sk_buff *ctx = NULL;
u32 retval, duration;
int hh_len = ETH_HLEN;
struct sk_buff *skb;
struct sock *sk;
void *data;
int ret;
if (kattr->test.flags || kattr->test.cpu)
return -EINVAL;
data = bpf_test_init(kattr, size, NET_SKB_PAD + NET_IP_ALIGN,
SKB_DATA_ALIGN(sizeof(struct skb_shared_info)));
if (IS_ERR(data))
return PTR_ERR(data);
ctx = bpf_ctx_init(kattr, sizeof(struct __sk_buff));
if (IS_ERR(ctx)) {
kfree(data);
return PTR_ERR(ctx);
}
switch (prog->type) {
case BPF_PROG_TYPE_SCHED_CLS:
case BPF_PROG_TYPE_SCHED_ACT:
is_l2 = true;
fallthrough;
case BPF_PROG_TYPE_LWT_IN:
case BPF_PROG_TYPE_LWT_OUT:
case BPF_PROG_TYPE_LWT_XMIT:
is_direct_pkt_access = true;
break;
default:
break;
}
sk = sk_alloc(net, AF_UNSPEC, GFP_USER, &bpf_dummy_proto, 1);
if (!sk) {
kfree(data);
kfree(ctx);
return -ENOMEM;
}
sock_init_data(NULL, sk);
skb = build_skb(data, 0);
if (!skb) {
kfree(data);
kfree(ctx);
sk_free(sk);
return -ENOMEM;
}
skb->sk = sk;
skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN);
__skb_put(skb, size);
if (ctx && ctx->ifindex > 1) {
dev = dev_get_by_index(net, ctx->ifindex);
if (!dev) {
ret = -ENODEV;
goto out;
}
}
skb->protocol = eth_type_trans(skb, dev);
skb_reset_network_header(skb);
switch (skb->protocol) {
case htons(ETH_P_IP):
sk->sk_family = AF_INET;
if (sizeof(struct iphdr) <= skb_headlen(skb)) {
sk->sk_rcv_saddr = ip_hdr(skb)->saddr;
sk->sk_daddr = ip_hdr(skb)->daddr;
}
break;
#if IS_ENABLED(CONFIG_IPV6)
case htons(ETH_P_IPV6):
sk->sk_family = AF_INET6;
if (sizeof(struct ipv6hdr) <= skb_headlen(skb)) {
sk->sk_v6_rcv_saddr = ipv6_hdr(skb)->saddr;
sk->sk_v6_daddr = ipv6_hdr(skb)->daddr;
}
break;
#endif
default:
break;
}
if (is_l2)
__skb_push(skb, hh_len);
if (is_direct_pkt_access)
bpf_compute_data_pointers(skb);
ret = convert___skb_to_skb(skb, ctx);
if (ret)
goto out;
ret = bpf_test_run(prog, skb, repeat, &retval, &duration, false);
if (ret)
goto out;
if (!is_l2) {
if (skb_headroom(skb) < hh_len) {
int nhead = HH_DATA_ALIGN(hh_len - skb_headroom(skb));
if (pskb_expand_head(skb, nhead, 0, GFP_USER)) {
ret = -ENOMEM;
goto out;
}
}
memset(__skb_push(skb, hh_len), 0, hh_len);
}
convert_skb_to___skb(skb, ctx);
size = skb->len;
/* bpf program can never convert linear skb to non-linear */
if (WARN_ON_ONCE(skb_is_nonlinear(skb)))
size = skb_headlen(skb);
ret = bpf_test_finish(kattr, uattr, skb->data, size, retval, duration);
if (!ret)
ret = bpf_ctx_finish(kattr, uattr, ctx,
sizeof(struct __sk_buff));
out:
if (dev && dev != net->loopback_dev)
dev_put(dev);
kfree_skb(skb);
sk_free(sk);
kfree(ctx);
return ret;
}
static int xdp_convert_md_to_buff(struct xdp_md *xdp_md, struct xdp_buff *xdp)
{
unsigned int ingress_ifindex, rx_queue_index;
struct netdev_rx_queue *rxqueue;
struct net_device *device;
if (!xdp_md)
return 0;
if (xdp_md->egress_ifindex != 0)
return -EINVAL;
ingress_ifindex = xdp_md->ingress_ifindex;
rx_queue_index = xdp_md->rx_queue_index;
if (!ingress_ifindex && rx_queue_index)
return -EINVAL;
if (ingress_ifindex) {
device = dev_get_by_index(current->nsproxy->net_ns,
ingress_ifindex);
if (!device)
return -ENODEV;
if (rx_queue_index >= device->real_num_rx_queues)
goto free_dev;
rxqueue = __netif_get_rx_queue(device, rx_queue_index);
if (!xdp_rxq_info_is_reg(&rxqueue->xdp_rxq))
goto free_dev;
xdp->rxq = &rxqueue->xdp_rxq;
/* The device is now tracked in the xdp->rxq for later
* dev_put()
*/
}
xdp->data = xdp->data_meta + xdp_md->data;
return 0;
free_dev:
dev_put(device);
return -EINVAL;
}
static void xdp_convert_buff_to_md(struct xdp_buff *xdp, struct xdp_md *xdp_md)
{
if (!xdp_md)
return;
xdp_md->data = xdp->data - xdp->data_meta;
xdp_md->data_end = xdp->data_end - xdp->data_meta;
if (xdp_md->ingress_ifindex)
dev_put(xdp->rxq->dev);
}
int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
union bpf_attr __user *uattr)
{
u32 tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
u32 headroom = XDP_PACKET_HEADROOM;
u32 size = kattr->test.data_size_in;
u32 repeat = kattr->test.repeat;
struct netdev_rx_queue *rxqueue;
struct xdp_buff xdp = {};
u32 retval, duration;
struct xdp_md *ctx;
u32 max_data_sz;
void *data;
int ret = -EINVAL;
if (prog->expected_attach_type == BPF_XDP_DEVMAP ||
prog->expected_attach_type == BPF_XDP_CPUMAP)
return -EINVAL;
ctx = bpf_ctx_init(kattr, sizeof(struct xdp_md));
if (IS_ERR(ctx))
return PTR_ERR(ctx);
if (ctx) {
/* There can't be user provided data before the meta data */
if (ctx->data_meta || ctx->data_end != size ||
ctx->data > ctx->data_end ||
unlikely(xdp_metalen_invalid(ctx->data)))
goto free_ctx;
/* Meta data is allocated from the headroom */
headroom -= ctx->data;
}
/* XDP have extra tailroom as (most) drivers use full page */
max_data_sz = 4096 - headroom - tailroom;
data = bpf_test_init(kattr, max_data_sz, headroom, tailroom);
if (IS_ERR(data)) {
ret = PTR_ERR(data);
goto free_ctx;
}
rxqueue = __netif_get_rx_queue(current->nsproxy->net_ns->loopback_dev, 0);
xdp_init_buff(&xdp, headroom + max_data_sz + tailroom,
&rxqueue->xdp_rxq);
xdp_prepare_buff(&xdp, data, headroom, size, true);
ret = xdp_convert_md_to_buff(ctx, &xdp);
if (ret)
goto free_data;
if (repeat > 1)
bpf_prog_change_xdp(NULL, prog);
ret = bpf_test_run(prog, &xdp, repeat, &retval, &duration, true);
/* We convert the xdp_buff back to an xdp_md before checking the return
* code so the reference count of any held netdevice will be decremented
* even if the test run failed.
*/
xdp_convert_buff_to_md(&xdp, ctx);
if (ret)
goto out;
if (xdp.data_meta != data + headroom ||
xdp.data_end != xdp.data_meta + size)
size = xdp.data_end - xdp.data_meta;
ret = bpf_test_finish(kattr, uattr, xdp.data_meta, size, retval,
duration);
if (!ret)
ret = bpf_ctx_finish(kattr, uattr, ctx,
sizeof(struct xdp_md));
out:
if (repeat > 1)
bpf_prog_change_xdp(prog, NULL);
free_data:
kfree(data);
free_ctx:
kfree(ctx);
return ret;
}
static int verify_user_bpf_flow_keys(struct bpf_flow_keys *ctx)
{
/* make sure the fields we don't use are zeroed */
if (!range_is_zero(ctx, 0, offsetof(struct bpf_flow_keys, flags)))
return -EINVAL;
/* flags is allowed */
if (!range_is_zero(ctx, offsetofend(struct bpf_flow_keys, flags),
sizeof(struct bpf_flow_keys)))
return -EINVAL;
return 0;
}
int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog,
const union bpf_attr *kattr,
union bpf_attr __user *uattr)
{
struct bpf_test_timer t = { NO_PREEMPT };
u32 size = kattr->test.data_size_in;
struct bpf_flow_dissector ctx = {};
u32 repeat = kattr->test.repeat;
struct bpf_flow_keys *user_ctx;
struct bpf_flow_keys flow_keys;
const struct ethhdr *eth;
unsigned int flags = 0;
u32 retval, duration;
void *data;
int ret;
if (prog->type != BPF_PROG_TYPE_FLOW_DISSECTOR)
return -EINVAL;
if (kattr->test.flags || kattr->test.cpu)
return -EINVAL;
if (size < ETH_HLEN)
return -EINVAL;
data = bpf_test_init(kattr, size, 0, 0);
if (IS_ERR(data))
return PTR_ERR(data);
eth = (struct ethhdr *)data;
if (!repeat)
repeat = 1;
user_ctx = bpf_ctx_init(kattr, sizeof(struct bpf_flow_keys));
if (IS_ERR(user_ctx)) {
kfree(data);
return PTR_ERR(user_ctx);
}
if (user_ctx) {
ret = verify_user_bpf_flow_keys(user_ctx);
if (ret)
goto out;
flags = user_ctx->flags;
}
ctx.flow_keys = &flow_keys;
ctx.data = data;
ctx.data_end = (__u8 *)data + size;
bpf_test_timer_enter(&t);
do {
retval = bpf_flow_dissect(prog, &ctx, eth->h_proto, ETH_HLEN,
size, flags);
} while (bpf_test_timer_continue(&t, repeat, &ret, &duration));
bpf_test_timer_leave(&t);
if (ret < 0)
goto out;
ret = bpf_test_finish(kattr, uattr, &flow_keys, sizeof(flow_keys),
retval, duration);
if (!ret)
ret = bpf_ctx_finish(kattr, uattr, user_ctx,
sizeof(struct bpf_flow_keys));
out:
kfree(user_ctx);
kfree(data);
return ret;
}
int bpf_prog_test_run_sk_lookup(struct bpf_prog *prog, const union bpf_attr *kattr,
union bpf_attr __user *uattr)
{
struct bpf_test_timer t = { NO_PREEMPT };
struct bpf_prog_array *progs = NULL;
struct bpf_sk_lookup_kern ctx = {};
u32 repeat = kattr->test.repeat;
struct bpf_sk_lookup *user_ctx;
u32 retval, duration;
int ret = -EINVAL;
if (prog->type != BPF_PROG_TYPE_SK_LOOKUP)
return -EINVAL;
if (kattr->test.flags || kattr->test.cpu)
return -EINVAL;
if (kattr->test.data_in || kattr->test.data_size_in || kattr->test.data_out ||
kattr->test.data_size_out)
return -EINVAL;
if (!repeat)
repeat = 1;
user_ctx = bpf_ctx_init(kattr, sizeof(*user_ctx));
if (IS_ERR(user_ctx))
return PTR_ERR(user_ctx);
if (!user_ctx)
return -EINVAL;
if (user_ctx->sk)
goto out;
if (!range_is_zero(user_ctx, offsetofend(typeof(*user_ctx), local_port), sizeof(*user_ctx)))
goto out;
if (user_ctx->local_port > U16_MAX || user_ctx->remote_port > U16_MAX) {
ret = -ERANGE;
goto out;
}
ctx.family = (u16)user_ctx->family;
ctx.protocol = (u16)user_ctx->protocol;
ctx.dport = (u16)user_ctx->local_port;
ctx.sport = (__force __be16)user_ctx->remote_port;
switch (ctx.family) {
case AF_INET:
ctx.v4.daddr = (__force __be32)user_ctx->local_ip4;
ctx.v4.saddr = (__force __be32)user_ctx->remote_ip4;
break;
#if IS_ENABLED(CONFIG_IPV6)
case AF_INET6:
ctx.v6.daddr = (struct in6_addr *)user_ctx->local_ip6;
ctx.v6.saddr = (struct in6_addr *)user_ctx->remote_ip6;
break;
#endif
default:
ret = -EAFNOSUPPORT;
goto out;
}
progs = bpf_prog_array_alloc(1, GFP_KERNEL);
if (!progs) {
ret = -ENOMEM;
goto out;
}
progs->items[0].prog = prog;
bpf_test_timer_enter(&t);
do {
ctx.selected_sk = NULL;
retval = BPF_PROG_SK_LOOKUP_RUN_ARRAY(progs, ctx, bpf_prog_run);
} while (bpf_test_timer_continue(&t, repeat, &ret, &duration));
bpf_test_timer_leave(&t);
if (ret < 0)
goto out;
user_ctx->cookie = 0;
if (ctx.selected_sk) {
if (ctx.selected_sk->sk_reuseport && !ctx.no_reuseport) {
ret = -EOPNOTSUPP;
goto out;
}
user_ctx->cookie = sock_gen_cookie(ctx.selected_sk);
}
ret = bpf_test_finish(kattr, uattr, NULL, 0, retval, duration);
if (!ret)
ret = bpf_ctx_finish(kattr, uattr, user_ctx, sizeof(*user_ctx));
out:
bpf_prog_array_free(progs);
kfree(user_ctx);
return ret;
}
int bpf_prog_test_run_syscall(struct bpf_prog *prog,
const union bpf_attr *kattr,
union bpf_attr __user *uattr)
{
void __user *ctx_in = u64_to_user_ptr(kattr->test.ctx_in);
__u32 ctx_size_in = kattr->test.ctx_size_in;
void *ctx = NULL;
u32 retval;
int err = 0;
/* doesn't support data_in/out, ctx_out, duration, or repeat or flags */
if (kattr->test.data_in || kattr->test.data_out ||
kattr->test.ctx_out || kattr->test.duration ||
kattr->test.repeat || kattr->test.flags)
return -EINVAL;
if (ctx_size_in < prog->aux->max_ctx_offset ||
ctx_size_in > U16_MAX)
return -EINVAL;
if (ctx_size_in) {
ctx = kzalloc(ctx_size_in, GFP_USER);
if (!ctx)
return -ENOMEM;
if (copy_from_user(ctx, ctx_in, ctx_size_in)) {
err = -EFAULT;
goto out;
}
}
rcu_read_lock_trace();
retval = bpf_prog_run_pin_on_cpu(prog, ctx);
rcu_read_unlock_trace();
if (copy_to_user(&uattr->test.retval, &retval, sizeof(u32))) {
err = -EFAULT;
goto out;
}
if (ctx_size_in)
if (copy_to_user(ctx_in, ctx, ctx_size_in))
err = -EFAULT;
out:
kfree(ctx);
return err;
}
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