linux/net/bpf/test_run.c
Lorenzo Bianconi a676308085 bpf: test_run: Fix OOB access in bpf_prog_test_run_xdp
Fix the following kasan issue reported by syzbot:

BUG: KASAN: slab-out-of-bounds in __skb_frag_set_page include/linux/skbuff.h:3242 [inline]
BUG: KASAN: slab-out-of-bounds in bpf_prog_test_run_xdp+0x10ac/0x1150 net/bpf/test_run.c:972
Write of size 8 at addr ffff888048c75000 by task syz-executor.5/23405

CPU: 1 PID: 23405 Comm: syz-executor.5 Not tainted 5.16.0-syzkaller #0
Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255
 __kasan_report mm/kasan/report.c:442 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
 __skb_frag_set_page include/linux/skbuff.h:3242 [inline]
 bpf_prog_test_run_xdp+0x10ac/0x1150 net/bpf/test_run.c:972
 bpf_prog_test_run kernel/bpf/syscall.c:3356 [inline]
 __sys_bpf+0x1858/0x59a0 kernel/bpf/syscall.c:4658
 __do_sys_bpf kernel/bpf/syscall.c:4744 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4742 [inline]
 __x64_sys_bpf+0x75/0xb0 kernel/bpf/syscall.c:4742
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f4ea30dd059
RSP: 002b:00007f4ea1a52168 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f4ea31eff60 RCX: 00007f4ea30dd059
RDX: 0000000000000048 RSI: 0000000020000000 RDI: 000000000000000a
RBP: 00007f4ea313708d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc8367c5af R14: 00007f4ea1a52300 R15: 0000000000022000
 </TASK>

Allocated by task 23405:
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:437 [inline]
 ____kasan_kmalloc mm/kasan/common.c:516 [inline]
 ____kasan_kmalloc mm/kasan/common.c:475 [inline]
 __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:525
 kmalloc include/linux/slab.h:586 [inline]
 kzalloc include/linux/slab.h:715 [inline]
 bpf_test_init.isra.0+0x9f/0x150 net/bpf/test_run.c:411
 bpf_prog_test_run_xdp+0x2f8/0x1150 net/bpf/test_run.c:941
 bpf_prog_test_run kernel/bpf/syscall.c:3356 [inline]
 __sys_bpf+0x1858/0x59a0 kernel/bpf/syscall.c:4658
 __do_sys_bpf kernel/bpf/syscall.c:4744 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4742 [inline]
 __x64_sys_bpf+0x75/0xb0 kernel/bpf/syscall.c:4742
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff888048c74000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 0 bytes to the right of
 4096-byte region [ffff888048c74000, ffff888048c75000)
The buggy address belongs to the page:
page:ffffea0001231c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x48c70
head:ffffea0001231c00 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010c42140
raw: 0000000000000000 0000000080040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
 prep_new_page mm/page_alloc.c:2434 [inline]
 get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389
 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2271
 alloc_slab_page mm/slub.c:1799 [inline]
 allocate_slab mm/slub.c:1944 [inline]
 new_slab+0x28a/0x3b0 mm/slub.c:2004
 ___slab_alloc+0x87c/0xe90 mm/slub.c:3018
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105
 slab_alloc_node mm/slub.c:3196 [inline]
 __kmalloc_node_track_caller+0x2cb/0x360 mm/slub.c:4957
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 __alloc_skb+0xde/0x340 net/core/skbuff.c:426
 alloc_skb include/linux/skbuff.h:1159 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:745 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:802 [inline]
 nsim_dev_trap_report_work+0x29a/0xbc0 drivers/net/netdevsim/dev.c:843
 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307
 worker_thread+0x657/0x1110 kernel/workqueue.c:2454
 kthread+0x2e9/0x3a0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1352 [inline]
 free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404
 free_unref_page_prepare mm/page_alloc.c:3325 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3404
 qlink_free mm/kasan/quarantine.c:157 [inline]
 qlist_free_all+0x6d/0x160 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:447
 kasan_slab_alloc include/linux/kasan.h:260 [inline]
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc_node mm/slub.c:3230 [inline]
 slab_alloc mm/slub.c:3238 [inline]
 kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3243
 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138
 getname_flags include/linux/audit.h:323 [inline]
 getname+0x8e/0xd0 fs/namei.c:217
 do_sys_openat2+0xf5/0x4d0 fs/open.c:1208
 do_sys_open fs/open.c:1230 [inline]
 __do_sys_openat fs/open.c:1246 [inline]
 __se_sys_openat fs/open.c:1241 [inline]
 __x64_sys_openat+0x13f/0x1f0 fs/open.c:1241
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Memory state around the buggy address:
 ffff888048c74f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888048c74f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                   ^
 ffff888048c75080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888048c75100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Fixes: 1c19499825 ("bpf: introduce frags support to bpf_prog_test_run_xdp()")
Reported-by: syzbot+6d70ca7438345077c549@syzkaller.appspotmail.com
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/688c26f9dd6e885e58e8e834ede3f0139bb7fa95.1643835097.git.lorenzo@kernel.org
2022-02-03 09:42:29 -08:00

1270 lines
29 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2017 Facebook
*/
#include <linux/bpf.h>
#include <linux/btf.h>
#include <linux/btf_ids.h>
#include <linux/slab.h>
#include <linux/init.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,
struct skb_shared_info *sinfo, 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) {
int len = sinfo ? copy_size - sinfo->xdp_frags_size : copy_size;
if (copy_to_user(data_out, data, len))
goto out;
if (sinfo) {
int i, offset = len, data_len;
for (i = 0; i < sinfo->nr_frags; i++) {
skb_frag_t *frag = &sinfo->frags[i];
if (offset >= copy_size) {
err = -ENOSPC;
break;
}
data_len = min_t(int, copy_size - offset,
skb_frag_size(frag));
if (copy_to_user(data_out + offset,
skb_frag_address(frag),
data_len))
goto out;
offset += data_len;
}
}
}
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;
}
EXPORT_SYMBOL_GPL(bpf_fentry_test1);
ALLOW_ERROR_INJECTION(bpf_fentry_test1, ERRNO);
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;
}
struct prog_test_ref_kfunc {
int a;
int b;
struct prog_test_ref_kfunc *next;
};
static struct prog_test_ref_kfunc prog_test_struct = {
.a = 42,
.b = 108,
.next = &prog_test_struct,
};
noinline struct prog_test_ref_kfunc *
bpf_kfunc_call_test_acquire(unsigned long *scalar_ptr)
{
/* randomly return NULL */
if (get_jiffies_64() % 2)
return NULL;
return &prog_test_struct;
}
noinline void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p)
{
}
struct prog_test_pass1 {
int x0;
struct {
int x1;
struct {
int x2;
struct {
int x3;
};
};
};
};
struct prog_test_pass2 {
int len;
short arr1[4];
struct {
char arr2[4];
unsigned long arr3[8];
} x;
};
struct prog_test_fail1 {
void *p;
int x;
};
struct prog_test_fail2 {
int x8;
struct prog_test_pass1 x;
};
struct prog_test_fail3 {
int len;
char arr1[2];
char arr2[];
};
noinline void bpf_kfunc_call_test_pass_ctx(struct __sk_buff *skb)
{
}
noinline void bpf_kfunc_call_test_pass1(struct prog_test_pass1 *p)
{
}
noinline void bpf_kfunc_call_test_pass2(struct prog_test_pass2 *p)
{
}
noinline void bpf_kfunc_call_test_fail1(struct prog_test_fail1 *p)
{
}
noinline void bpf_kfunc_call_test_fail2(struct prog_test_fail2 *p)
{
}
noinline void bpf_kfunc_call_test_fail3(struct prog_test_fail3 *p)
{
}
noinline void bpf_kfunc_call_test_mem_len_pass1(void *mem, int mem__sz)
{
}
noinline void bpf_kfunc_call_test_mem_len_fail1(void *mem, int len)
{
}
noinline void bpf_kfunc_call_test_mem_len_fail2(u64 *mem, int len)
{
}
__diag_pop();
ALLOW_ERROR_INJECTION(bpf_modify_return_test, ERRNO);
BTF_SET_START(test_sk_check_kfunc_ids)
BTF_ID(func, bpf_kfunc_call_test1)
BTF_ID(func, bpf_kfunc_call_test2)
BTF_ID(func, bpf_kfunc_call_test3)
BTF_ID(func, bpf_kfunc_call_test_acquire)
BTF_ID(func, bpf_kfunc_call_test_release)
BTF_ID(func, bpf_kfunc_call_test_pass_ctx)
BTF_ID(func, bpf_kfunc_call_test_pass1)
BTF_ID(func, bpf_kfunc_call_test_pass2)
BTF_ID(func, bpf_kfunc_call_test_fail1)
BTF_ID(func, bpf_kfunc_call_test_fail2)
BTF_ID(func, bpf_kfunc_call_test_fail3)
BTF_ID(func, bpf_kfunc_call_test_mem_len_pass1)
BTF_ID(func, bpf_kfunc_call_test_mem_len_fail1)
BTF_ID(func, bpf_kfunc_call_test_mem_len_fail2)
BTF_SET_END(test_sk_check_kfunc_ids)
BTF_SET_START(test_sk_acquire_kfunc_ids)
BTF_ID(func, bpf_kfunc_call_test_acquire)
BTF_SET_END(test_sk_acquire_kfunc_ids)
BTF_SET_START(test_sk_release_kfunc_ids)
BTF_ID(func, bpf_kfunc_call_test_release)
BTF_SET_END(test_sk_release_kfunc_ids)
BTF_SET_START(test_sk_ret_null_kfunc_ids)
BTF_ID(func, bpf_kfunc_call_test_acquire)
BTF_SET_END(test_sk_ret_null_kfunc_ids)
static void *bpf_test_init(const union bpf_attr *kattr, u32 user_size,
u32 size, u32 headroom, u32 tailroom)
{
void __user *data_in = u64_to_user_ptr(kattr->test.data_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 = memdup_user(ctx_in, ctx_size_in);
if (IS_ERR(info.ctx))
return PTR_ERR(info.ctx);
} 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;
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, kattr->test.data_size_in,
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, NULL, 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 size = kattr->test.data_size_in;
u32 headroom = XDP_PACKET_HEADROOM;
u32 retval, duration, max_data_sz;
u32 repeat = kattr->test.repeat;
struct netdev_rx_queue *rxqueue;
struct skb_shared_info *sinfo;
struct xdp_buff xdp = {};
int i, ret = -EINVAL;
struct xdp_md *ctx;
void *data;
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;
}
max_data_sz = 4096 - headroom - tailroom;
size = min_t(u32, size, max_data_sz);
data = bpf_test_init(kattr, size, 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);
rxqueue->xdp_rxq.frag_size = headroom + max_data_sz + tailroom;
xdp_init_buff(&xdp, rxqueue->xdp_rxq.frag_size, &rxqueue->xdp_rxq);
xdp_prepare_buff(&xdp, data, headroom, size, true);
sinfo = xdp_get_shared_info_from_buff(&xdp);
ret = xdp_convert_md_to_buff(ctx, &xdp);
if (ret)
goto free_data;
if (unlikely(kattr->test.data_size_in > size)) {
void __user *data_in = u64_to_user_ptr(kattr->test.data_in);
while (size < kattr->test.data_size_in) {
struct page *page;
skb_frag_t *frag;
int data_len;
if (sinfo->nr_frags == MAX_SKB_FRAGS) {
ret = -ENOMEM;
goto out;
}
page = alloc_page(GFP_KERNEL);
if (!page) {
ret = -ENOMEM;
goto out;
}
frag = &sinfo->frags[sinfo->nr_frags++];
__skb_frag_set_page(frag, page);
data_len = min_t(int, kattr->test.data_size_in - size,
PAGE_SIZE);
skb_frag_size_set(frag, data_len);
if (copy_from_user(page_address(page), data_in + size,
data_len)) {
ret = -EFAULT;
goto out;
}
sinfo->xdp_frags_size += data_len;
size += data_len;
}
xdp_buff_set_frags_flag(&xdp);
}
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;
size = xdp.data_end - xdp.data_meta + sinfo->xdp_frags_size;
ret = bpf_test_finish(kattr, uattr, xdp.data_meta, sinfo, 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:
for (i = 0; i < sinfo->nr_frags; i++)
__free_page(skb_frag_page(&sinfo->frags[i]));
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, kattr->test.data_size_in, 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, NULL,
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, 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 = memdup_user(ctx_in, ctx_size_in);
if (IS_ERR(ctx))
return PTR_ERR(ctx);
}
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;
}
static const struct btf_kfunc_id_set bpf_prog_test_kfunc_set = {
.owner = THIS_MODULE,
.check_set = &test_sk_check_kfunc_ids,
.acquire_set = &test_sk_acquire_kfunc_ids,
.release_set = &test_sk_release_kfunc_ids,
.ret_null_set = &test_sk_ret_null_kfunc_ids,
};
static int __init bpf_prog_test_run_init(void)
{
return register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &bpf_prog_test_kfunc_set);
}
late_initcall(bpf_prog_test_run_init);