xref: /kernel/linux/linux-6.6/tools/testing/selftests/bpf/progs/verifier_unpriv.c

// SPDX-License-Identifier: GPL-2.0
/* Converted from tools/testing/selftests/bpf/verifier/unpriv.c */

#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include "../../../include/linux/filter.h"
#include "bpf_misc.h"

#define BPF_SK_LOOKUP(func) \
	/* struct bpf_sock_tuple tuple = {} */ \
	"r2 = 0;"			\
	"*(u32*)(r10 - 8) = r2;"	\
	"*(u64*)(r10 - 16) = r2;"	\
	"*(u64*)(r10 - 24) = r2;"	\
	"*(u64*)(r10 - 32) = r2;"	\
	"*(u64*)(r10 - 40) = r2;"	\
	"*(u64*)(r10 - 48) = r2;"	\
	/* sk = func(ctx, &tuple, sizeof tuple, 0, 0) */ \
	"r2 = r10;"			\
	"r2 += -48;"			\
	"r3 = %[sizeof_bpf_sock_tuple];"\
	"r4 = 0;"			\
	"r5 = 0;"			\
	"call %[" #func "];"

struct {
	__uint(type, BPF_MAP_TYPE_HASH);
	__uint(max_entries, 1);
	__type(key, long long);
	__type(value, long long);
} map_hash_8b SEC(".maps");

void dummy_prog_42_socket(void);
void dummy_prog_24_socket(void);
void dummy_prog_loop1_socket(void);

struct {
	__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
	__uint(max_entries, 4);
	__uint(key_size, sizeof(int));
	__array(values, void (void));
} map_prog1_socket SEC(".maps") = {
	.values = {
		[0] = (void *)&dummy_prog_42_socket,
		[1] = (void *)&dummy_prog_loop1_socket,
		[2] = (void *)&dummy_prog_24_socket,
	},
};

SEC("socket")
__auxiliary __auxiliary_unpriv
__naked void dummy_prog_42_socket(void)
{
	asm volatile ("r0 = 42; exit;");
}

SEC("socket")
__auxiliary __auxiliary_unpriv
__naked void dummy_prog_24_socket(void)
{
	asm volatile ("r0 = 24; exit;");
}

SEC("socket")
__auxiliary __auxiliary_unpriv
__naked void dummy_prog_loop1_socket(void)
{
	asm volatile ("			\
	r3 = 1;				\
	r2 = %[map_prog1_socket] ll;	\
	call %[bpf_tail_call];		\
	r0 = 41;			\
	exit;				\
"	:
	: __imm(bpf_tail_call),
	  __imm_addr(map_prog1_socket)
	: __clobber_all);
}

SEC("socket")
__description("unpriv: return pointer")
__success __failure_unpriv __msg_unpriv("R0 leaks addr")
__retval(POINTER_VALUE)
__naked void unpriv_return_pointer(void)
{
	asm volatile ("					\
	r0 = r10;					\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: add const to pointer")
__success __success_unpriv __retval(0)
__naked void unpriv_add_const_to_pointer(void)
{
	asm volatile ("					\
	r1 += 8;					\
	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: add pointer to pointer")
__failure __msg("R1 pointer += pointer")
__failure_unpriv
__naked void unpriv_add_pointer_to_pointer(void)
{
	asm volatile ("					\
	r1 += r10;					\
	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: neg pointer")
__success __failure_unpriv __msg_unpriv("R1 pointer arithmetic")
__retval(0)
__naked void unpriv_neg_pointer(void)
{
	asm volatile ("					\
	r1 = -r1;					\
	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: cmp pointer with const")
__success __failure_unpriv __msg_unpriv("R1 pointer comparison")
__retval(0)
__naked void unpriv_cmp_pointer_with_const(void)
{
	asm volatile ("					\
	if r1 == 0 goto l0_%=;				\
l0_%=:	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: cmp pointer with pointer")
__success __failure_unpriv __msg_unpriv("R10 pointer comparison")
__retval(0)
__naked void unpriv_cmp_pointer_with_pointer(void)
{
	asm volatile ("					\
	if r1 == r10 goto l0_%=;			\
l0_%=:	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("tracepoint")
__description("unpriv: check that printk is disallowed")
__success
__naked void check_that_printk_is_disallowed(void)
{
	asm volatile ("					\
	r1 = 0;						\
	*(u64*)(r10 - 8) = r1;				\
	r1 = r10;					\
	r1 += -8;					\
	r2 = 8;						\
	r3 = r1;					\
	call %[bpf_trace_printk];			\
	r0 = 0;						\
	exit;						\
"	:
	: __imm(bpf_trace_printk)
	: __clobber_all);
}

SEC("socket")
__description("unpriv: pass pointer to helper function")
__success __failure_unpriv __msg_unpriv("R4 leaks addr")
__retval(0)
__naked void pass_pointer_to_helper_function(void)
{
	asm volatile ("					\
	r1 = 0;						\
	*(u64*)(r10 - 8) = r1;				\
	r2 = r10;					\
	r2 += -8;					\
	r1 = %[map_hash_8b] ll;				\
	r3 = r2;					\
	r4 = r2;					\
	call %[bpf_map_update_elem];			\
	r0 = 0;						\
	exit;						\
"	:
	: __imm(bpf_map_update_elem),
	  __imm_addr(map_hash_8b)
	: __clobber_all);
}

SEC("socket")
__description("unpriv: indirectly pass pointer on stack to helper function")
__success __failure_unpriv
__msg_unpriv("invalid indirect read from stack R2 off -8+0 size 8")
__retval(0)
__naked void on_stack_to_helper_function(void)
{
	asm volatile ("					\
	*(u64*)(r10 - 8) = r10;				\
	r2 = r10;					\
	r2 += -8;					\
	r1 = %[map_hash_8b] ll;				\
	call %[bpf_map_lookup_elem];			\
	r0 = 0;						\
	exit;						\
"	:
	: __imm(bpf_map_lookup_elem),
	  __imm_addr(map_hash_8b)
	: __clobber_all);
}

SEC("socket")
__description("unpriv: mangle pointer on stack 1")
__success __failure_unpriv __msg_unpriv("attempt to corrupt spilled")
__retval(0)
__naked void mangle_pointer_on_stack_1(void)
{
	asm volatile ("					\
	*(u64*)(r10 - 8) = r10;				\
	r0 = 0;						\
	*(u32*)(r10 - 8) = r0;				\
	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: mangle pointer on stack 2")
__success __failure_unpriv __msg_unpriv("attempt to corrupt spilled")
__retval(0)
__naked void mangle_pointer_on_stack_2(void)
{
	asm volatile ("					\
	*(u64*)(r10 - 8) = r10;				\
	r0 = 0;						\
	*(u8*)(r10 - 1) = r0;				\
	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: read pointer from stack in small chunks")
__failure __msg("invalid size")
__failure_unpriv
__naked void from_stack_in_small_chunks(void)
{
	asm volatile ("					\
	*(u64*)(r10 - 8) = r10;				\
	r0 = *(u32*)(r10 - 8);				\
	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: write pointer into ctx")
__failure __msg("invalid bpf_context access")
__failure_unpriv __msg_unpriv("R1 leaks addr")
__naked void unpriv_write_pointer_into_ctx(void)
{
	asm volatile ("					\
	*(u64*)(r1 + 0) = r1;				\
	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: spill/fill of ctx")
__success __success_unpriv __retval(0)
__naked void unpriv_spill_fill_of_ctx(void)
{
	asm volatile ("					\
	r6 = r10;					\
	r6 += -8;					\
	*(u64*)(r6 + 0) = r1;				\
	r1 = *(u64*)(r6 + 0);				\
	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("tc")
__description("unpriv: spill/fill of ctx 2")
__success __retval(0)
__naked void spill_fill_of_ctx_2(void)
{
	asm volatile ("					\
	r6 = r10;					\
	r6 += -8;					\
	*(u64*)(r6 + 0) = r1;				\
	r1 = *(u64*)(r6 + 0);				\
	call %[bpf_get_hash_recalc];			\
	r0 = 0;						\
	exit;						\
"	:
	: __imm(bpf_get_hash_recalc)
	: __clobber_all);
}

SEC("tc")
__description("unpriv: spill/fill of ctx 3")
__failure __msg("R1 type=fp expected=ctx")
__naked void spill_fill_of_ctx_3(void)
{
	asm volatile ("					\
	r6 = r10;					\
	r6 += -8;					\
	*(u64*)(r6 + 0) = r1;				\
	*(u64*)(r6 + 0) = r10;				\
	r1 = *(u64*)(r6 + 0);				\
	call %[bpf_get_hash_recalc];			\
	exit;						\
"	:
	: __imm(bpf_get_hash_recalc)
	: __clobber_all);
}

SEC("tc")
__description("unpriv: spill/fill of ctx 4")
__failure __msg("R1 type=scalar expected=ctx")
__naked void spill_fill_of_ctx_4(void)
{
	asm volatile ("					\
	r6 = r10;					\
	r6 += -8;					\
	*(u64*)(r6 + 0) = r1;				\
	r0 = 1;						\
	lock *(u64 *)(r10 - 8) += r0;			\
	r1 = *(u64*)(r6 + 0);				\
	call %[bpf_get_hash_recalc];			\
	exit;						\
"	:
	: __imm(bpf_get_hash_recalc)
	: __clobber_all);
}

SEC("tc")
__description("unpriv: spill/fill of different pointers stx")
__failure __msg("same insn cannot be used with different pointers")
__naked void fill_of_different_pointers_stx(void)
{
	asm volatile ("					\
	r3 = 42;					\
	r6 = r10;					\
	r6 += -8;					\
	if r1 == 0 goto l0_%=;				\
	r2 = r10;					\
	r2 += -16;					\
	*(u64*)(r6 + 0) = r2;				\
l0_%=:	if r1 != 0 goto l1_%=;				\
	*(u64*)(r6 + 0) = r1;				\
l1_%=:	r1 = *(u64*)(r6 + 0);				\
	*(u32*)(r1 + %[__sk_buff_mark]) = r3;		\
	r0 = 0;						\
	exit;						\
"	:
	: __imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark))
	: __clobber_all);
}

/* Same as above, but use BPF_ST_MEM to save 42
 * instead of BPF_STX_MEM.
 */
SEC("tc")
__description("unpriv: spill/fill of different pointers st")
__failure __msg("same insn cannot be used with different pointers")
__naked void fill_of_different_pointers_st(void)
{
	asm volatile ("					\
	r6 = r10;					\
	r6 += -8;					\
	if r1 == 0 goto l0_%=;				\
	r2 = r10;					\
	r2 += -16;					\
	*(u64*)(r6 + 0) = r2;				\
l0_%=:	if r1 != 0 goto l1_%=;				\
	*(u64*)(r6 + 0) = r1;				\
l1_%=:	r1 = *(u64*)(r6 + 0);				\
	.8byte %[st_mem];				\
	r0 = 0;						\
	exit;						\
"	:
	: __imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark)),
	  __imm_insn(st_mem,
		     BPF_ST_MEM(BPF_W, BPF_REG_1, offsetof(struct __sk_buff, mark), 42))
	: __clobber_all);
}

SEC("tc")
__description("unpriv: spill/fill of different pointers stx - ctx and sock")
__failure __msg("type=ctx expected=sock")
__naked void pointers_stx_ctx_and_sock(void)
{
	asm volatile ("					\
	r8 = r1;					\
	/* struct bpf_sock *sock = bpf_sock_lookup(...); */\
"	BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
"	r2 = r0;					\
	/* u64 foo; */					\
	/* void *target = &foo; */			\
	r6 = r10;					\
	r6 += -8;					\
	r1 = r8;					\
	/* if (skb == NULL) *target = sock; */		\
	if r1 == 0 goto l0_%=;				\
	*(u64*)(r6 + 0) = r2;				\
l0_%=:	/* else *target = skb; */			\
	if r1 != 0 goto l1_%=;				\
	*(u64*)(r6 + 0) = r1;				\
l1_%=:	/* struct __sk_buff *skb = *target; */		\
	r1 = *(u64*)(r6 + 0);				\
	/* skb->mark = 42; */				\
	r3 = 42;					\
	*(u32*)(r1 + %[__sk_buff_mark]) = r3;		\
	/* if (sk) bpf_sk_release(sk) */		\
	if r1 == 0 goto l2_%=;				\
	call %[bpf_sk_release];				\
l2_%=:	r0 = 0;						\
	exit;						\
"	:
	: __imm(bpf_sk_lookup_tcp),
	  __imm(bpf_sk_release),
	  __imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark)),
	  __imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
	: __clobber_all);
}

SEC("tc")
__description("unpriv: spill/fill of different pointers stx - leak sock")
__failure
//.errstr = "same insn cannot be used with different pointers",
__msg("Unreleased reference")
__naked void different_pointers_stx_leak_sock(void)
{
	asm volatile ("					\
	r8 = r1;					\
	/* struct bpf_sock *sock = bpf_sock_lookup(...); */\
"	BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
"	r2 = r0;					\
	/* u64 foo; */					\
	/* void *target = &foo; */			\
	r6 = r10;					\
	r6 += -8;					\
	r1 = r8;					\
	/* if (skb == NULL) *target = sock; */		\
	if r1 == 0 goto l0_%=;				\
	*(u64*)(r6 + 0) = r2;				\
l0_%=:	/* else *target = skb; */			\
	if r1 != 0 goto l1_%=;				\
	*(u64*)(r6 + 0) = r1;				\
l1_%=:	/* struct __sk_buff *skb = *target; */		\
	r1 = *(u64*)(r6 + 0);				\
	/* skb->mark = 42; */				\
	r3 = 42;					\
	*(u32*)(r1 + %[__sk_buff_mark]) = r3;		\
	exit;						\
"	:
	: __imm(bpf_sk_lookup_tcp),
	  __imm_const(__sk_buff_mark, offsetof(struct __sk_buff, mark)),
	  __imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
	: __clobber_all);
}

SEC("tc")
__description("unpriv: spill/fill of different pointers stx - sock and ctx (read)")
__failure __msg("same insn cannot be used with different pointers")
__naked void stx_sock_and_ctx_read(void)
{
	asm volatile ("					\
	r8 = r1;					\
	/* struct bpf_sock *sock = bpf_sock_lookup(...); */\
"	BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
"	r2 = r0;					\
	/* u64 foo; */					\
	/* void *target = &foo; */			\
	r6 = r10;					\
	r6 += -8;					\
	r1 = r8;					\
	/* if (skb) *target = skb */			\
	if r1 == 0 goto l0_%=;				\
	*(u64*)(r6 + 0) = r1;				\
l0_%=:	/* else *target = sock */			\
	if r1 != 0 goto l1_%=;				\
	*(u64*)(r6 + 0) = r2;				\
l1_%=:	/* struct bpf_sock *sk = *target; */		\
	r1 = *(u64*)(r6 + 0);				\
	/* if (sk) u32 foo = sk->mark; bpf_sk_release(sk); */\
	if r1 == 0 goto l2_%=;				\
	r3 = *(u32*)(r1 + %[bpf_sock_mark]);		\
	call %[bpf_sk_release];				\
l2_%=:	r0 = 0;						\
	exit;						\
"	:
	: __imm(bpf_sk_lookup_tcp),
	  __imm(bpf_sk_release),
	  __imm_const(bpf_sock_mark, offsetof(struct bpf_sock, mark)),
	  __imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
	: __clobber_all);
}

SEC("tc")
__description("unpriv: spill/fill of different pointers stx - sock and ctx (write)")
__failure
//.errstr = "same insn cannot be used with different pointers",
__msg("cannot write into sock")
__naked void stx_sock_and_ctx_write(void)
{
	asm volatile ("					\
	r8 = r1;					\
	/* struct bpf_sock *sock = bpf_sock_lookup(...); */\
"	BPF_SK_LOOKUP(bpf_sk_lookup_tcp)
"	r2 = r0;					\
	/* u64 foo; */					\
	/* void *target = &foo; */			\
	r6 = r10;					\
	r6 += -8;					\
	r1 = r8;					\
	/* if (skb) *target = skb */			\
	if r1 == 0 goto l0_%=;				\
	*(u64*)(r6 + 0) = r1;				\
l0_%=:	/* else *target = sock */			\
	if r1 != 0 goto l1_%=;				\
	*(u64*)(r6 + 0) = r2;				\
l1_%=:	/* struct bpf_sock *sk = *target; */		\
	r1 = *(u64*)(r6 + 0);				\
	/* if (sk) sk->mark = 42; bpf_sk_release(sk); */\
	if r1 == 0 goto l2_%=;				\
	r3 = 42;					\
	*(u32*)(r1 + %[bpf_sock_mark]) = r3;		\
	call %[bpf_sk_release];				\
l2_%=:	r0 = 0;						\
	exit;						\
"	:
	: __imm(bpf_sk_lookup_tcp),
	  __imm(bpf_sk_release),
	  __imm_const(bpf_sock_mark, offsetof(struct bpf_sock, mark)),
	  __imm_const(sizeof_bpf_sock_tuple, sizeof(struct bpf_sock_tuple))
	: __clobber_all);
}

SEC("socket")
__description("unpriv: write pointer into map elem value")
__success __failure_unpriv __msg_unpriv("R0 leaks addr")
__retval(0)
__naked void pointer_into_map_elem_value(void)
{
	asm volatile ("					\
	r1 = 0;						\
	*(u64*)(r10 - 8) = r1;				\
	r2 = r10;					\
	r2 += -8;					\
	r1 = %[map_hash_8b] ll;				\
	call %[bpf_map_lookup_elem];			\
	if r0 == 0 goto l0_%=;				\
	*(u64*)(r0 + 0) = r0;				\
l0_%=:	exit;						\
"	:
	: __imm(bpf_map_lookup_elem),
	  __imm_addr(map_hash_8b)
	: __clobber_all);
}

SEC("socket")
__description("alu32: mov u32 const")
__success __failure_unpriv __msg_unpriv("R7 invalid mem access 'scalar'")
__retval(0)
__naked void alu32_mov_u32_const(void)
{
	asm volatile ("					\
	w7 = 0;						\
	w7 &= 1;					\
	w0 = w7;					\
	if r0 == 0 goto l0_%=;				\
	r0 = *(u64*)(r7 + 0);				\
l0_%=:	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: partial copy of pointer")
__success __failure_unpriv __msg_unpriv("R10 partial copy")
__retval(0)
__naked void unpriv_partial_copy_of_pointer(void)
{
	asm volatile ("					\
	w1 = w10;					\
	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: pass pointer to tail_call")
__success __failure_unpriv __msg_unpriv("R3 leaks addr into helper")
__retval(0)
__naked void pass_pointer_to_tail_call(void)
{
	asm volatile ("					\
	r3 = r1;					\
	r2 = %[map_prog1_socket] ll;			\
	call %[bpf_tail_call];				\
	r0 = 0;						\
	exit;						\
"	:
	: __imm(bpf_tail_call),
	  __imm_addr(map_prog1_socket)
	: __clobber_all);
}

SEC("socket")
__description("unpriv: cmp map pointer with zero")
__success __failure_unpriv __msg_unpriv("R1 pointer comparison")
__retval(0)
__naked void cmp_map_pointer_with_zero(void)
{
	asm volatile ("					\
	r1 = 0;						\
	r1 = %[map_hash_8b] ll;				\
	if r1 == 0 goto l0_%=;				\
l0_%=:	r0 = 0;						\
	exit;						\
"	:
	: __imm_addr(map_hash_8b)
	: __clobber_all);
}

SEC("socket")
__description("unpriv: write into frame pointer")
__failure __msg("frame pointer is read only")
__failure_unpriv
__naked void unpriv_write_into_frame_pointer(void)
{
	asm volatile ("					\
	r10 = r1;					\
	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: spill/fill frame pointer")
__failure __msg("frame pointer is read only")
__failure_unpriv
__naked void unpriv_spill_fill_frame_pointer(void)
{
	asm volatile ("					\
	r6 = r10;					\
	r6 += -8;					\
	*(u64*)(r6 + 0) = r10;				\
	r10 = *(u64*)(r6 + 0);				\
	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: cmp of frame pointer")
__success __failure_unpriv __msg_unpriv("R10 pointer comparison")
__retval(0)
__naked void unpriv_cmp_of_frame_pointer(void)
{
	asm volatile ("					\
	if r10 == 0 goto l0_%=;				\
l0_%=:	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: adding of fp, reg")
__success __failure_unpriv
__msg_unpriv("R1 stack pointer arithmetic goes out of range")
__retval(0)
__naked void unpriv_adding_of_fp_reg(void)
{
	asm volatile ("					\
	r0 = 0;						\
	r1 = 0;						\
	r1 += r10;					\
	*(u64*)(r1 - 8) = r0;				\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: adding of fp, imm")
__success __failure_unpriv
__msg_unpriv("R1 stack pointer arithmetic goes out of range")
__retval(0)
__naked void unpriv_adding_of_fp_imm(void)
{
	asm volatile ("					\
	r0 = 0;						\
	r1 = r10;					\
	r1 += 0;					\
	*(u64*)(r1 - 8) = r0;				\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("unpriv: cmp of stack pointer")
__success __failure_unpriv __msg_unpriv("R2 pointer comparison")
__retval(0)
__naked void unpriv_cmp_of_stack_pointer(void)
{
	asm volatile ("					\
	r2 = r10;					\
	r2 += -8;					\
	if r2 == 0 goto l0_%=;				\
l0_%=:	r0 = 0;						\
	exit;						\
"	::: __clobber_all);
}

char _license[] SEC("license") = "GPL";