BPF List
 help / color / mirror / Atom feed
From: Andrii Nakryiko <andrii@kernel.org>
To: <bpf@vger.kernel.org>, <ast@kernel.org>, <daniel@iogearbox.net>,
	<martin.lau@kernel.org>
Cc: <andrii@kernel.org>, <kernel-team@meta.com>
Subject: [PATCH bpf-next 02/10] bpf: provide correct register name for exception callback retval check
Date: Tue, 21 Nov 2023 17:16:48 -0800	[thread overview]
Message-ID: <20231122011656.1105943-3-andrii@kernel.org> (raw)
In-Reply-To: <20231122011656.1105943-1-andrii@kernel.org>

bpf_throw() is checking R1, so let's report R1 in the log.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
---
 kernel/bpf/verifier.c                                | 12 ++++++------
 .../testing/selftests/bpf/progs/exceptions_assert.c  |  2 +-
 tools/testing/selftests/bpf/progs/exceptions_fail.c  |  2 +-
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 8c2d31aa3d31..a921dba4f603 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -11663,7 +11663,7 @@ static int fetch_kfunc_meta(struct bpf_verifier_env *env,
 	return 0;
 }
 
-static int check_return_code(struct bpf_verifier_env *env, int regno);
+static int check_return_code(struct bpf_verifier_env *env, int regno, const char *reg_name);
 
 static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
 			    int *insn_idx_p)
@@ -11799,7 +11799,7 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
 		 * to bpf_throw becomes the return value of the program.
 		 */
 		if (!env->exception_callback_subprog) {
-			err = check_return_code(env, BPF_REG_1);
+			err = check_return_code(env, BPF_REG_1, "R1");
 			if (err < 0)
 				return err;
 		}
@@ -14818,7 +14818,7 @@ static int check_ld_abs(struct bpf_verifier_env *env, struct bpf_insn *insn)
 	return 0;
 }
 
-static int check_return_code(struct bpf_verifier_env *env, int regno)
+static int check_return_code(struct bpf_verifier_env *env, int regno, const char *reg_name)
 {
 	struct tnum enforce_attach_type_range = tnum_unknown;
 	const struct bpf_prog *prog = env->prog;
@@ -14872,7 +14872,7 @@ static int check_return_code(struct bpf_verifier_env *env, int regno)
 		}
 
 		if (!tnum_in(const_0, reg->var_off)) {
-			verbose_invalid_scalar(env, reg, &const_0, "async callback", "R0");
+			verbose_invalid_scalar(env, reg, &const_0, "async callback", reg_name);
 			return -EINVAL;
 		}
 		return 0;
@@ -14972,7 +14972,7 @@ static int check_return_code(struct bpf_verifier_env *env, int regno)
 	}
 
 	if (!tnum_in(range, reg->var_off)) {
-		verbose_invalid_scalar(env, reg, &range, "program exit", "R0");
+		verbose_invalid_scalar(env, reg, &range, "program exit", reg_name);
 		if (prog->expected_attach_type == BPF_LSM_CGROUP &&
 		    prog_type == BPF_PROG_TYPE_LSM &&
 		    !prog->aux->attach_func_proto->type)
@@ -17220,7 +17220,7 @@ static int do_check(struct bpf_verifier_env *env)
 					continue;
 				}
 
-				err = check_return_code(env, BPF_REG_0);
+				err = check_return_code(env, BPF_REG_0, "R0");
 				if (err)
 					return err;
 process_bpf_exit:
diff --git a/tools/testing/selftests/bpf/progs/exceptions_assert.c b/tools/testing/selftests/bpf/progs/exceptions_assert.c
index 49efaed143fc..575e7dd719c4 100644
--- a/tools/testing/selftests/bpf/progs/exceptions_assert.c
+++ b/tools/testing/selftests/bpf/progs/exceptions_assert.c
@@ -125,7 +125,7 @@ int check_assert_generic(struct __sk_buff *ctx)
 }
 
 SEC("?fentry/bpf_check")
-__failure __msg("At program exit the register R0 has value (0x40; 0x0)")
+__failure __msg("At program exit the register R1 has value (0x40; 0x0)")
 int check_assert_with_return(void *ctx)
 {
 	bpf_assert_with(!ctx, 64);
diff --git a/tools/testing/selftests/bpf/progs/exceptions_fail.c b/tools/testing/selftests/bpf/progs/exceptions_fail.c
index 4c39e920dac2..69a8fb53ea1d 100644
--- a/tools/testing/selftests/bpf/progs/exceptions_fail.c
+++ b/tools/testing/selftests/bpf/progs/exceptions_fail.c
@@ -306,7 +306,7 @@ int reject_set_exception_cb_bad_ret1(void *ctx)
 }
 
 SEC("?fentry/bpf_check")
-__failure __msg("At program exit the register R0 has value (0x40; 0x0) should")
+__failure __msg("At program exit the register R1 has value (0x40; 0x0) should")
 int reject_set_exception_cb_bad_ret2(void *ctx)
 {
 	bpf_throw(64);
-- 
2.34.1


  parent reply	other threads:[~2023-11-22  1:17 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-11-22  1:16 [PATCH bpf-next 00/10] BPF verifier retval logic fixes Andrii Nakryiko
2023-11-22  1:16 ` [PATCH bpf-next 01/10] bpf: rearrange bpf_func_state fields to save a bit of memory Andrii Nakryiko
2023-11-22 15:12   ` Eduard Zingerman
2023-11-22  1:16 ` Andrii Nakryiko [this message]
2023-11-22 15:12   ` [PATCH bpf-next 02/10] bpf: provide correct register name for exception callback retval check Eduard Zingerman
2023-11-23  1:44   ` Alexei Starovoitov
2023-11-24  3:39     ` Andrii Nakryiko
2023-11-22  1:16 ` [PATCH bpf-next 03/10] bpf: enforce precision of R0 on callback return Andrii Nakryiko
2023-11-22 15:12   ` Eduard Zingerman
2023-11-22  1:16 ` [PATCH bpf-next 04/10] bpf: enforce exact retval range on subprog/callback exit Andrii Nakryiko
2023-11-22 15:13   ` Eduard Zingerman
2023-11-22 17:45     ` Andrii Nakryiko
2023-11-27 10:55       ` Shung-Hsi Yu
2023-11-27 18:19         ` Andrii Nakryiko
2023-11-22  1:16 ` [PATCH bpf-next 05/10] selftests/bpf: add selftest validating callback result is enforced Andrii Nakryiko
2023-11-22 15:13   ` Eduard Zingerman
2023-11-22 17:46     ` Andrii Nakryiko
2023-11-22  1:16 ` [PATCH bpf-next 06/10] bpf: enforce precise retval range on program exit Andrii Nakryiko
2023-11-22 15:13   ` Eduard Zingerman
2023-11-22  1:16 ` [PATCH bpf-next 07/10] bpf: unify async callback and program retval checks Andrii Nakryiko
2023-11-22 15:13   ` Eduard Zingerman
2023-11-22  1:16 ` [PATCH bpf-next 08/10] bpf: enforce precision of R0 on program/async callback return Andrii Nakryiko
2023-11-22 15:13   ` Eduard Zingerman
2023-11-22  1:16 ` [PATCH bpf-next 09/10] selftests/bpf: validate async callback return value check correctness Andrii Nakryiko
2023-11-22 15:13   ` Eduard Zingerman
2023-11-22  1:16 ` [PATCH bpf-next 10/10] selftests/bpf: adjust global_func15 test to validate prog exit precision Andrii Nakryiko
2023-11-22 15:13   ` Eduard Zingerman

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20231122011656.1105943-3-andrii@kernel.org \
    --to=andrii@kernel.org \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=kernel-team@meta.com \
    --cc=martin.lau@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox