Commit 18cdc2b5 authored by Eduard Zingerman's avatar Eduard Zingerman Committed by Alexei Starovoitov
Browse files

selftests/bpf: verifier/raw_tp_writable.c converted to inline assembly 



Test verifier/raw_tp_writable.c automatically converted to use inline assembly.

Signed-off-by: default avatarEduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20230325025524.144043-33-eddyz87@gmail.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 5a77a01f

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

+2 −0
Original line number Diff line number Diff line
@@ -29,6 +29,7 @@ 
#include "verifier_masking.skel.h"

#include "verifier_meta_access.skel.h"

#include "verifier_raw_stack.skel.h"

#include "verifier_raw_tp_writable.skel.h"



__maybe_unused

static void run_tests_aux(const char *skel_name, skel_elf_bytes_fn elf_bytes_factory)
@@ -80,3 +81,4 @@ 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_raw_stack(void)            { RUN(verifier_raw_stack); }

void test_verifier_raw_tp_writable(void)      { RUN(verifier_raw_tp_writable); }

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

0 → 100644
+50 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/* Converted from tools/testing/selftests/bpf/verifier/raw_tp_writable.c */



#include <linux/bpf.h>

#include <bpf/bpf_helpers.h>

#include "bpf_misc.h"



struct {

	__uint(type, BPF_MAP_TYPE_HASH);

	__uint(max_entries, 1);

	__type(key, long long);

	__type(value, long long);

} map_hash_8b SEC(".maps");



SEC("raw_tracepoint.w")

__description("raw_tracepoint_writable: reject variable offset")

__failure

__msg("R6 invalid variable buffer offset: off=0, var_off=(0x0; 0xffffffff)")

__flag(BPF_F_ANY_ALIGNMENT)

__naked void tracepoint_writable_reject_variable_offset(void)

{

	asm volatile ("					\

	/* r6 is our tp buffer */			\

	r6 = *(u64*)(r1 + 0);				\

	r1 = %[map_hash_8b] ll;				\

	/* move the key (== 0) to r10-8 */		\

	w0 = 0;						\

	r2 = r10;					\

	r2 += -8;					\

	*(u64*)(r2 + 0) = r0;				\

	/* lookup in the map */				\

	call %[bpf_map_lookup_elem];			\

	/* exit clean if null */			\

	if r0 != 0 goto l0_%=;				\

	exit;						\

l0_%=:	/* shift the buffer pointer to a variable location */\

	r0 = *(u32*)(r0 + 0);				\

	r6 += r0;					\

	/* clobber whatever's there */			\

	r7 = 4242;					\

	*(u64*)(r6 + 0) = r7;				\

	r0 = 0;						\

	exit;						\

"	:

	: __imm(bpf_map_lookup_elem),

	  __imm_addr(map_hash_8b)

	: __clobber_all);

}



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

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

deleted100644 → 0
+0 −35
Original line number Diff line number Diff line 
{

	"raw_tracepoint_writable: reject variable offset",

	.insns = {

		/* r6 is our tp buffer */

		BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 0),



		BPF_LD_MAP_FD(BPF_REG_1, 0),

		/* move the key (== 0) to r10-8 */

		BPF_MOV32_IMM(BPF_REG_0, 0),

		BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),

		BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),

		BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_0, 0),

		/* lookup in the map */

		BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,

			     BPF_FUNC_map_lookup_elem),



		/* exit clean if null */

		BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),

		BPF_EXIT_INSN(),



		/* shift the buffer pointer to a variable location */

		BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_0, 0),

		BPF_ALU64_REG(BPF_ADD, BPF_REG_6, BPF_REG_0),

		/* clobber whatever's there */

		BPF_MOV64_IMM(BPF_REG_7, 4242),

		BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_7, 0),



		BPF_MOV64_IMM(BPF_REG_0, 0),

		BPF_EXIT_INSN(),

	},

	.fixup_map_hash_8b = { 1, },

	.prog_type = BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,

	.errstr = "R6 invalid variable buffer offset: off=0, var_off=(0x0; 0xffffffff)",

	.flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,

},