From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 565C94432FD for ; Thu, 8 Oct 2026 08:13:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.71 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791447208; cv=none; b=f8J9tPebUgdRGce+gCKNvg1bNMuDbZtkgLpsC5mEbHY3gJPHMb0V8Iqi+WPDfzkPGrSdlCuRuKLMGU3FFly58bO+b7iRf588T7NEY+S+ifFqxQUfCH6MWSlDRN/NjTGH9Kqo3AMTMT3pwzlGbIQSI8auzNjatq4PHSQ6p1QWFE0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791447208; c=relaxed/simple; bh=sAZmrQfFRnvX1r8inqgJzOXyhociMrhtZR2BILeJs6Q=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=pe9JqhygjYRvs4wNkiy3n2YccWmG5YcDyQWRRwYs8NW3Hs5V1YFJ1CxR2B85DFD9Y7sQQhpRgrrzKfxVlez2aSnM/Ut3Ke5KcFfaKZ6nsJ5IR2zrQjKoiELbcvUKLjUNSNBSNy3pnmc6il6BcWf9zg8g/a5qN92XwsvLevoCKxQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--ardb.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=KgIe5lFH; arc=none smtp.client-ip=209.85.128.71 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--ardb.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="KgIe5lFH" Received: by mail-wm1-f71.google.com with SMTP id 5b1f17b1804b1-4a1813fea7dso20064815e9.2 for ; Thu, 08 Oct 2026 01:13:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1791447205; x=1792052005; darn=vger.kernel.org; h=content-transfer-encoding:content-type:cc:to:from:subject :message-id:references:mime-version:in-reply-to:date:from:to:cc :subject:date:message-id:reply-to:content-type; bh=16FkECH/P3PnGGILReivsLQaUXwzid4+SEzG39QlygM=; b=KgIe5lFHx/WAS1J7kIPZ7fTh/bjldsMB/DW/zw2awPIUGMvy3Py9ktEZeiIfAdGFPz A7ej0tfXYqR7Cnp04PR61YcOHFv9Wi05t6IKkkMENv+UHiwGHKpAVRBLtPtdk4EWemxj p4Bay7/E0UcKfbDu3qk85z/3lYUvIU0WWFdWEmxcl0/oAOc8CUWl907X9uwS9nJo5Elf AHYS2ZXbBsHqZeGTLTzlhJUsmp7axaCqMiiTlSr+u/BoBhh13CakEHa20pvWZwyLp6sb B16n8ddbo8kpV6KzKti2PTTOYtV8WKAqclDpOEiYuMmHTzyBGvYlUhZLMfBZjPKofBuE GXjw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1791447205; x=1792052005; h=content-transfer-encoding:content-type:cc:to:from:subject :message-id:references:mime-version:in-reply-to:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=16FkECH/P3PnGGILReivsLQaUXwzid4+SEzG39QlygM=; b=PakpWFFpqPzbVLJ9G9QwX9LkRmSrJy7/pSNapJ2QvRGR10i8gV9XUiVlLPXrVnqNZX 4Sajdwj2Mtx1x9hbELTOetWhdAhbAOfo4dYe8iQae3JXPNfUFgpsiohMp324AmeMJ7uv 5NvIEO4/F/UuN7wmKeUraNJhIC0OejvxPqRAw5uenibj6/KOJGxR0ZUpqa7Tj3BeSp0a 4qe1CEWwmZU/oGQILVLdnW/Pgiaa4ZDadwiXA/RPSBJhbqU8lGNvXOTkCx0a0TQe1Bzc Jb1iWVcJmJSCu/mE0K9J/eiaCHcQ0V1D3GmT2UEXTDrJFyLIWI3b1nAlYxeNb7CBwO7c g50A== X-Gm-Message-State: AFuF++mVLmKNc8d/tovI5W/Us0z2dY7alSg6OBXfnBLptv5HEdWbMYH0 t/s1NwhvlTrduqG2k0OZa3M30jYIZtcwL5BN5nKHP4rt9tos/L0oIduLJcxnAiaxNkJWicOQ+g= = X-Received: from wmgb18.prod.google.com ([2002:a05:600c:1512:b0:4a0:1976:e6a3]) (user=ardb job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:4e87:b0:49f:bd3c:bc18 with SMTP id 5b1f17b1804b1-4a18045565cmr81178025e9.19.1791447205382; Thu, 08 Oct 2026 01:13:25 -0700 (PDT) Date: Thu, 8 Oct 2026 10:13:20 +0200 In-Reply-To: <20261008081317.2602565-4-ardb+git@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20261008081317.2602565-4-ardb+git@google.com> X-Mailer: git-send-email 2.56.0.360.g66cac248cb-goog Message-ID: <20261008081317.2602565-6-ardb+git@google.com> Subject: [PATCH v2 2/2] efi: Use sysfs_emit() not sprintf() to generate sysfs file contents From: Ard Biesheuvel To: linux-efi@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Ard Biesheuvel , "=?UTF-8?q?Thomas=20Wei=C3=9Fschuh?=" Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable From: Ard Biesheuvel Use sysfs_emit() where appropriate to generate the contents of EFI related sysfs nodes. This is a more robust wrapper around sprintf() designed for this purpose. Reported-by: Thomas Wei=C3=9Fschuh Signed-off-by: Ard Biesheuvel --- arch/x86/platform/efi/efi.c | 2 +- drivers/firmware/efi/efi.c | 16 ++++++++-------- 2 files changed, 9 insertions(+), 9 deletions(-) diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index d8fe93770c2a..5eb96c17883e 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -893,7 +893,7 @@ bool efi_is_table_address(unsigned long phys_addr) static ssize_t name##_show(struct kobject *kobj, \ const struct kobj_attribute *attr, char *buf) \ { \ - return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \ + return sysfs_emit(buf, "0x%lx\n", EFI_FIELD(name)); \ } =20 EFI_ATTR_SHOW(fw_vendor); diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 8026264d4990..b4504542cb2c 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -133,26 +133,26 @@ struct kobject *efi_kobj; static ssize_t systab_show(struct kobject *kobj, const struct kobj_attribute *attr, char *buf) { - char *str =3D buf; + int offset =3D 0; =20 if (!kobj || !buf) return -EINVAL; =20 if (efi.acpi20 !=3D EFI_INVALID_TABLE_ADDR) - str +=3D sprintf(str, "ACPI20=3D0x%lx\n", efi.acpi20); + offset =3D sysfs_emit(buf, "ACPI20=3D0x%lx\n", efi.acpi20); if (efi.acpi !=3D EFI_INVALID_TABLE_ADDR) - str +=3D sprintf(str, "ACPI=3D0x%lx\n", efi.acpi); + offset +=3D sysfs_emit_at(buf, offset, "ACPI=3D0x%lx\n", efi.acpi); /* * If both SMBIOS and SMBIOS3 entry points are implemented, the * SMBIOS3 entry point shall be preferred, so we list it first to * let applications stop parsing after the first match. */ if (efi.smbios3 !=3D EFI_INVALID_TABLE_ADDR) - str +=3D sprintf(str, "SMBIOS3=3D0x%lx\n", efi.smbios3); + offset +=3D sysfs_emit_at(buf, offset, "SMBIOS3=3D0x%lx\n", efi.smbios3)= ; if (efi.smbios !=3D EFI_INVALID_TABLE_ADDR) - str +=3D sprintf(str, "SMBIOS=3D0x%lx\n", efi.smbios); + offset +=3D sysfs_emit_at(buf, offset, "SMBIOS=3D0x%lx\n", efi.smbios); =20 - return str - buf; + return offset; } =20 static const struct kobj_attribute efi_attr_systab =3D __KOBJ_ATTR_RO_MODE= (systab, 0400); @@ -160,7 +160,7 @@ static const struct kobj_attribute efi_attr_systab =3D = __KOBJ_ATTR_RO_MODE(systab, static ssize_t fw_platform_size_show(struct kobject *kobj, const struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32); + return sysfs_emit(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32); } =20 extern __weak const struct kobj_attribute efi_attr_fw_vendor; @@ -406,7 +406,7 @@ static ssize_t efi_runtime_show(struct kobject *kobj, const struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%d\n", efi_enabled(EFI_RUNTIME_SERVICES)); + return sysfs_emit(buf, "%d\n", efi_enabled(EFI_RUNTIME_SERVICES)); } =20 static ssize_t efi_runtime_store(struct kobject *kobj, --=20 2.56.0.360.g66cac248cb-goog