selftests/bpf: Add unit tests for new sign-extension mov insns

Add unit tests for movsx insns.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20230728011309.3719295-1-yonghong.song@linux.devSigned-off-by: Alexei Starovoitov <ast@kernel.org>

tools/testing/selftests/bpf/prog_tests/verifier.c

@@ -41,6 +41,7 @@
 #include "verifier_map_ret_val.skel.h"
 #include "verifier_masking.skel.h"
 #include "verifier_meta_access.skel.h"
+#include "verifier_movsx.skel.h"
 #include "verifier_netfilter_ctx.skel.h"
 #include "verifier_netfilter_retcode.skel.h"
 #include "verifier_prevent_map_lookup.skel.h"
@@ -144,6 +145,7 @@ void test_verifier_map_ptr_mixing(void)       { RUN(verifier_map_ptr_mixing); }
 void test_verifier_map_ret_val(void)          { RUN(verifier_map_ret_val); }
 void test_verifier_masking(void)              { RUN(verifier_masking); }
 void test_verifier_meta_access(void)          { RUN(verifier_meta_access); }
+void test_verifier_movsx(void)                 { RUN(verifier_movsx); }
 void test_verifier_netfilter_ctx(void)        { RUN(verifier_netfilter_ctx); }
 void test_verifier_netfilter_retcode(void)    { RUN(verifier_netfilter_retcode); }
 void test_verifier_prevent_map_lookup(void)   { RUN(verifier_prevent_map_lookup); }

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

+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+#if defined(__TARGET_ARCH_x86) && __clang_major__ >= 18
+
+SEC("socket")
+__description("MOV32SX, S8")
+__success __success_unpriv __retval(0x23)
+__naked void mov32sx_s8(void)
+{
+	asm volatile ("					\
+	w0 = 0xff23;					\
+	w0 = (s8)w0;					\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("socket")
+__description("MOV32SX, S16")
+__success __success_unpriv __retval(0xFFFFff23)
+__naked void mov32sx_s16(void)
+{
+	asm volatile ("					\
+	w0 = 0xff23;					\
+	w0 = (s16)w0;					\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("socket")
+__description("MOV64SX, S8")
+__success __success_unpriv __retval(-2)
+__naked void mov64sx_s8(void)
+{
+	asm volatile ("					\
+	r0 = 0x1fe;					\
+	r0 = (s8)r0;					\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("socket")
+__description("MOV64SX, S16")
+__success __success_unpriv __retval(0xf23)
+__naked void mov64sx_s16(void)
+{
+	asm volatile ("					\
+	r0 = 0xf0f23;					\
+	r0 = (s16)r0;					\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("socket")
+__description("MOV64SX, S32")
+__success __success_unpriv __retval(-1)
+__naked void mov64sx_s32(void)
+{
+	asm volatile ("					\
+	r0 = 0xfffffffe;				\
+	r0 = (s32)r0;					\
+	r0 >>= 1;					\
+	exit;						\
+"	::: __clobber_all);
+}
+
+SEC("socket")
+__description("MOV32SX, S8, range_check")
+__success __success_unpriv __retval(1)
+__naked void mov32sx_s8_range(void)
+{
+	asm volatile ("					\
+	call %[bpf_get_prandom_u32];			\
+	w1 = (s8)w0;					\
+	/* w1 with s8 range */				\
+	if w1 s> 0x7f goto l0_%=;			\
+	if w1 s< -0x80 goto l0_%=;			\
+	r0 = 1;						\
+l1_%=:							\
+	exit;						\
+l0_%=:							\
+	r0 = 2;						\
+	goto l1_%=;					\
+"	:
+	: __imm(bpf_get_prandom_u32)
+	: __clobber_all);
+}
+
+SEC("socket")
+__description("MOV32SX, S16, range_check")
+__success __success_unpriv __retval(1)
+__naked void mov32sx_s16_range(void)
+{
+	asm volatile ("					\
+	call %[bpf_get_prandom_u32];			\
+	w1 = (s16)w0;					\
+	/* w1 with s16 range */				\
+	if w1 s> 0x7fff goto l0_%=;			\
+	if w1 s< -0x80ff goto l0_%=;			\
+	r0 = 1;						\
+l1_%=:							\
+	exit;						\
+l0_%=:							\
+	r0 = 2;						\
+	goto l1_%=;					\
+"	:
+	: __imm(bpf_get_prandom_u32)
+	: __clobber_all);
+}
+
+SEC("socket")
+__description("MOV32SX, S16, range_check 2")
+__success __success_unpriv __retval(1)
+__naked void mov32sx_s16_range_2(void)
+{
+	asm volatile ("					\
+	r1 = 65535;					\
+	w2 = (s16)w1;					\
+	r2 >>= 1;					\
+	if r2 != 0x7fffFFFF goto l0_%=;			\
+	r0 = 1;						\
+l1_%=:							\
+	exit;						\
+l0_%=:							\
+	r0 = 0;						\
+	goto l1_%=;					\
+"	:
+	: __imm(bpf_get_prandom_u32)
+	: __clobber_all);
+}
+
+SEC("socket")
+__description("MOV64SX, S8, range_check")
+__success __success_unpriv __retval(1)
+__naked void mov64sx_s8_range(void)
+{
+	asm volatile ("					\
+	call %[bpf_get_prandom_u32];			\
+	r1 = (s8)r0;					\
+	/* 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("MOV64SX, S16, range_check")
+__success __success_unpriv __retval(1)
+__naked void mov64sx_s16_range(void)
+{
+	asm volatile ("					\
+	call %[bpf_get_prandom_u32];			\
+	r1 = (s16)r0;					\
+	/* 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("MOV64SX, S32, range_check")
+__success __success_unpriv __retval(1)
+__naked void mov64sx_s32_range(void)
+{
+	asm volatile ("					\
+	call %[bpf_get_prandom_u32];			\
+	r1 = (s32)r0;					\
+	/* r1 with s32 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";