From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-174.mta0.migadu.com (out-174.mta0.migadu.com [91.218.175.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DA7273FE651 for ; Wed, 13 May 2026 11:58:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778673500; cv=none; b=lG8CCSAT/f/pF4BYddFA0sxO1bJQBhNlFuGC7BS8kA8UwVhkXoUiSu2ADJH9ltr7cZRUy8c0CmFP6zhewvwBVFaIhEnR7U5G15K8RNgOwY7O/kWkgBj+GXmsFpeJidXrHCXZETV5b2XoJxUHVKWuwaJaCGQCCnPnHjH/+esUxn0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778673500; c=relaxed/simple; bh=86KR6ysRrOFZZ3Ztz7ike1WiQ1Qtx2XB5IZuIv60m1c=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=kbybh5Etj+ti6E5Nc5cGiKRJHBtVlbtKInaXcU9KRUKtIFVR6fUOSIPX9AySgYDhMxFLZP7AUfNhfDsYB4x3h17soLsVI4DbVKVFFjl4XeFrCIoi1a7ueLJRmgJZaPfH0Y5kImTAes55krho1UexgPxn9wamtgj2ffXlNwi3ps4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=VrdfOcau; arc=none smtp.client-ip=91.218.175.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="VrdfOcau" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1778673495; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=BWkCz+DqFTW7wt2D8of+2AGF26ajnxS3iJv9/ADODgY=; b=VrdfOcauiFN5qDLFCLBeLAA6nq75l8wwLg5R7Bic6nYZqEnjZcSNYnxweNnKkHhRvcZ8ZB A1c8ZOy/pHTwCFaLNekV2WDAD3HqjCRnDduPSn3IJTfQ8iSNtjLpJCYy+UtpHXJ1XO3Dsz YsTrGvHO//YRJm3XFpSDGU53PpNOhBA= From: Thorsten Blum To: Catalin Marinas , Will Deacon , shechenglong , Zenghui Yu , Kuninori Morimoto , Jonathan Marek , Jinqian Yang Cc: Thorsten Blum , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH] arm64: proton-pack: use sysfs_emit in sysfs show functions Date: Wed, 13 May 2026 13:57:55 +0200 Message-ID: <20260513115756.447661-2-thorsten.blum@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2798; i=thorsten.blum@linux.dev; h=from:subject; bh=86KR6ysRrOFZZ3Ztz7ike1WiQ1Qtx2XB5IZuIv60m1c=; b=owGbwMvMwCUWt7pQ4caZUj3G02pJDFks6S4ZXmUl/y7EP3hgvcZNyuJkylw9xffrKq4eSrx/h PvT58eGHaUsDGJcDLJiiiwPZv2Y4VtaU7nJJGInzBxWJpAhDFycAjCRe22MDAfXnbzFvUbKcn+I Xdbx++G+bteDL6VdXeItuarowS7fIwEM/5N2T9kQIDgp+7+L3WNLt607ck+JvQ65vENf1P1o64T aTywA X-Developer-Key: i=thorsten.blum@linux.dev; a=openpgp; fpr=1D60735E8AEF3BE473B69D84733678FD8DFEEAD4 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT Replace sprintf() with sysfs_emit() in sysfs show functions, which is preferred for formatting sysfs output because it provides safer bounds checking. While the current code only emits fixed strings that fit easily within PAGE_SIZE, use sysfs_emit() to follow secure coding best practices. Signed-off-by: Thorsten Blum --- arch/arm64/kernel/proton-pack.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/arch/arm64/kernel/proton-pack.c b/arch/arm64/kernel/proton-pack.c index b3801f532b10..7bb6553fec08 100644 --- a/arch/arm64/kernel/proton-pack.c +++ b/arch/arm64/kernel/proton-pack.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include @@ -61,7 +62,7 @@ static void update_mitigation_state(enum mitigation_state *oldp, ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, char *buf) { - return sprintf(buf, "Mitigation: __user pointer sanitization\n"); + return sysfs_emit(buf, "Mitigation: __user pointer sanitization\n"); } /* @@ -126,7 +127,7 @@ ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, switch (spectre_v2_state) { case SPECTRE_UNAFFECTED: if (bhb_state == SPECTRE_UNAFFECTED) - return sprintf(buf, "Not affected\n"); + return sysfs_emit(buf, "Not affected\n"); /* * Platforms affected by Spectre-BHB can't report @@ -136,13 +137,13 @@ ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, fallthrough; case SPECTRE_MITIGATED: if (bhb_state == SPECTRE_MITIGATED && _unprivileged_ebpf_enabled()) - return sprintf(buf, "Vulnerable: Unprivileged eBPF enabled\n"); + return sysfs_emit(buf, "Vulnerable: Unprivileged eBPF enabled\n"); - return sprintf(buf, "Mitigation: %s%s\n", v2_str, bhb_str); + return sysfs_emit(buf, "Mitigation: %s%s\n", v2_str, bhb_str); case SPECTRE_VULNERABLE: fallthrough; default: - return sprintf(buf, "Vulnerable\n"); + return sysfs_emit(buf, "Vulnerable\n"); } } @@ -438,13 +439,13 @@ ssize_t cpu_show_spec_store_bypass(struct device *dev, { switch (spectre_v4_state) { case SPECTRE_UNAFFECTED: - return sprintf(buf, "Not affected\n"); + return sysfs_emit(buf, "Not affected\n"); case SPECTRE_MITIGATED: - return sprintf(buf, "Mitigation: Speculative Store Bypass disabled via prctl\n"); + return sysfs_emit(buf, "Mitigation: Speculative Store Bypass disabled via prctl\n"); case SPECTRE_VULNERABLE: fallthrough; default: - return sprintf(buf, "Vulnerable\n"); + return sysfs_emit(buf, "Vulnerable\n"); } }