tools/testing/selftests/bpf/progs/verifier_ldsx.c

// SPDX-License-Identifier: GPL-2.0

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

#if (defined(__TARGET_ARCH_arm64) || defined(__TARGET_ARCH_x86) || \
     (defined(__TARGET_ARCH_riscv) && __riscv_xlen == 64)) && __clang_major__ >= 18

SEC("socket")
__description("LDSX, S8")
__success __success_unpriv __retval(-2)
__naked void ldsx_s8(void)
{
	asm volatile ("					\
	r1 = 0x3fe;					\
	*(u64 *)(r10 - 8) = r1;				\
	r0 = *(s8 *)(r10 - 8);				\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("LDSX, S16")
__success __success_unpriv __retval(-2)
__naked void ldsx_s16(void)
{
	asm volatile ("					\
	r1 = 0x3fffe;					\
	*(u64 *)(r10 - 8) = r1;				\
	r0 = *(s16 *)(r10 - 8);				\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("LDSX, S32")
__success __success_unpriv __retval(-1)
__naked void ldsx_s32(void)
{
	asm volatile ("					\
	r1 = 0xfffffffe;				\
	*(u64 *)(r10 - 8) = r1;				\
	r0 = *(s32 *)(r10 - 8);				\
	r0 >>= 1;					\
	exit;						\
"	::: __clobber_all);
}

SEC("socket")
__description("LDSX, S8 range checking, privileged")
__log_level(2) __success __retval(1)
__msg("R1_w=scalar(smin=-128,smax=127)")
__naked void ldsx_s8_range_priv(void)
{
	asm volatile ("					\
	call %[bpf_get_prandom_u32];			\
	*(u64 *)(r10 - 8) = r0;				\
	r1 = *(s8 *)(r10 - 8);				\
	/* r1 with s8 range */				\
	if r1 s> 0x7f goto l0_%=;			\
	if r1 s< -0x80 goto l0_%=;			\
	r0 = 1;						\
l1_%=:							\
	exit;						\
l0_%=:							\
	r0 = 2;						\
	goto l1_%=;					\
"	:
	: __imm(bpf_get_prandom_u32)
	: __clobber_all);
}

SEC("socket")
__description("LDSX, S16 range checking")
__success __success_unpriv __retval(1)
__naked void ldsx_s16_range(void)
{
	asm volatile ("					\
	call %[bpf_get_prandom_u32];			\
	*(u64 *)(r10 - 8) = r0;				\
	r1 = *(s16 *)(r10 - 8);				\
	/* r1 with s16 range */				\
	if r1 s> 0x7fff goto l0_%=;			\
	if r1 s< -0x8000 goto l0_%=;			\
	r0 = 1;						\
l1_%=:							\
	exit;						\
l0_%=:							\
	r0 = 2;						\
	goto l1_%=;					\
"	:
	: __imm(bpf_get_prandom_u32)
	: __clobber_all);
}

SEC("socket")
__description("LDSX, S32 range checking")
__success __success_unpriv __retval(1)
__naked void ldsx_s32_range(void)
{
	asm volatile ("					\
	call %[bpf_get_prandom_u32];			\
	*(u64 *)(r10 - 8) = r0;				\
	r1 = *(s32 *)(r10 - 8);				\
	/* r1 with s16 range */				\
	if r1 s> 0x7fffFFFF goto l0_%=;			\
	if r1 s< -0x80000000 goto l0_%=;		\
	r0 = 1;						\
l1_%=:							\
	exit;						\
l0_%=:							\
	r0 = 2;						\
	goto l1_%=;					\
"	:
	: __imm(bpf_get_prandom_u32)
	: __clobber_all);
}

#else

SEC("socket")
__description("cpuv4 is not supported by compiler or jit, use a dummy test")
__success
int dummy_test(void)
{
	return 0;
}

#endif

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