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From: Kui-Feng Lee <thinker.li@gmail.com>
To: bpf@vger.kernel.org, ast@kernel.org, martin.lau@linux.dev,
	song@kernel.org, kernel-team@meta.com, andrii@kernel.org
Cc: sinquersw@gmail.com, kuifeng@meta.com,
	Kui-Feng Lee <thinker.li@gmail.com>
Subject: [PATCH bpf-next 02/11] bpf: Remove unnecessary call to btf_field_type_size().
Date: Tue,  9 Apr 2024 17:41:41 -0700	[thread overview]
Message-ID: <20240410004150.2917641-3-thinker.li@gmail.com> (raw)
In-Reply-To: <20240410004150.2917641-1-thinker.li@gmail.com>

field->size has been initialized by bpf_parse_fields() with the value
returned by btf_field_type_size(). Use it instead of calling
btf_field_type_size() again.

Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
---
 kernel/bpf/btf.c      | 2 +-
 kernel/bpf/verifier.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 90c4a32d89ff..e71ea78a4db9 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -6672,7 +6672,7 @@ int btf_struct_access(struct bpf_verifier_log *log,
 		for (i = 0; i < rec->cnt; i++) {
 			struct btf_field *field = &rec->fields[i];
 			u32 offset = field->offset;
-			if (off < offset + btf_field_type_size(field->type) && offset < off + size) {
+			if (off < offset + field->size && offset < off + size) {
 				bpf_log(log,
 					"direct access to %s is disallowed\n",
 					btf_field_type_name(field->type));
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 0d44940c12d2..86adacc5f76c 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -5432,7 +5432,7 @@ static int check_map_access(struct bpf_verifier_env *env, u32 regno,
 		 * this program. To check that [x1, x2) overlaps with [y1, y2),
 		 * it is sufficient to check x1 < y2 && y1 < x2.
 		 */
-		if (reg->smin_value + off < p + btf_field_type_size(field->type) &&
+		if (reg->smin_value + off < p + field->size &&
 		    p < reg->umax_value + off + size) {
 			switch (field->type) {
 			case BPF_KPTR_UNREF:
-- 
2.34.1


  parent reply	other threads:[~2024-04-10  0:41 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-04-10  0:41 [PATCH bpf-next 00/11] Enable BPF programs to declare arrays of kptr, bpf_rb_root, and bpf_list_head Kui-Feng Lee
2024-04-10  0:41 ` [PATCH bpf-next 01/11] bpf: Remove unnecessary checks on the offset of btf_field Kui-Feng Lee
2024-04-11 22:12   ` Eduard Zingerman
2024-04-10  0:41 ` Kui-Feng Lee [this message]
2024-04-11 22:12   ` [PATCH bpf-next 02/11] bpf: Remove unnecessary call to btf_field_type_size() Eduard Zingerman
2024-04-10  0:41 ` [PATCH bpf-next 03/11] bpf: Add nelems to struct btf_field_info and btf_field Kui-Feng Lee
2024-04-10  0:41 ` [PATCH bpf-next 04/11] bpf: check_map_kptr_access() compute the offset from the reg state Kui-Feng Lee
2024-04-11 22:13   ` Eduard Zingerman
2024-04-12  4:00     ` Kui-Feng Lee
2024-04-10  0:41 ` [PATCH bpf-next 05/11] bpf: initialize/free array of btf_field(s) Kui-Feng Lee
2024-04-11 22:13   ` Eduard Zingerman
2024-04-12  3:56     ` Kui-Feng Lee
2024-04-12 15:32       ` Eduard Zingerman
2024-04-12 17:00         ` Kui-Feng Lee
2024-04-10  0:41 ` [PATCH bpf-next 06/11] bpf: Find btf_field with the knowledge of arrays Kui-Feng Lee
2024-04-11 22:14   ` Eduard Zingerman
2024-04-12  2:00     ` Kui-Feng Lee
2024-04-10  0:41 ` [PATCH bpf-next 07/11] bpf: check_map_access() " Kui-Feng Lee
2024-04-11 22:14   ` Eduard Zingerman
2024-04-12 16:32     ` Kui-Feng Lee
2024-04-12 19:08       ` Eduard Zingerman
2024-04-12 19:29         ` Kui-Feng Lee
2024-04-12 19:50           ` Eduard Zingerman
2024-04-10  0:41 ` [PATCH bpf-next 08/11] bpf: Enable and verify btf_field arrays Kui-Feng Lee
2024-04-10  0:41 ` [PATCH bpf-next 09/11] selftests/bpf: Test global kptr arrays Kui-Feng Lee
2024-04-10  0:41 ` [PATCH bpf-next 10/11] selftests/bpf: Test global bpf_rb_root arrays Kui-Feng Lee
2024-04-10  0:41 ` [PATCH bpf-next 11/11] selftests/bpf: Test global bpf_list_head arrays Kui-Feng Lee

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