From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 81C302EB84E; Sat, 19 Sep 2026 00:27:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789777642; cv=none; b=EDC6LUWETZLqlUKoBWOz7bfhPQlKvgZvxRtFLBeoB0dwqqBe2wRkStg/AHXEzKz4rUOwG07a9x+r5Zcu+uGWKgEwTjaVXq6MePYJx1uBMl0AC54QbEXs65GK+RyoAnIr8vozAxXRTvjtK5Gm0gi5y4aM3MyYnFNv6ScCLh/4iOE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789777642; c=relaxed/simple; bh=bM8pfQZ+WNZUIhOsBdyOBh8XaXJCdRjSK82ONfe5d+M=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=PAj34yjakwo549UTjng/uOUn7YopElTMmvmQ0eVSHDIq5iv02Rcx8ZZSHMSUwuj3B1UA34vZSxHe6TirNgXRE8Dk+yfVzJLkzR21yOBaR4E6wYYkodAf/boAR9fVaLGMbJWBSn5f1eG5RlKMgdUsZQEqrypva+5g2VqLHDpywWQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=XNPJ9uuR; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="XNPJ9uuR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CEC581F008A3; Sat, 19 Sep 2026 00:27:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789777634; bh=ftDDqlFj8bU4K3fZAI2KjolyAI1cAmHP/993JbsJZpk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=XNPJ9uuRW7nHkAe0zYCwlX2SunjF2FSmGpgZdg1DSUad6q05ouhfyh5UiNpDupU63 3vo8uZexVw01RHe/7NfbrnrfMzfFQb1VHrk+I39LUsK+Cd8zR46JHcPR7VM8Mxfm4C 2OrUgqs7MqHrrf65btj9O1uonyEhtrQthpoOL39X+xWcdvk+rAqB7mw8Bsy7YhQ7Nt viBoT/KJCfByM4CqQkiRfCCgPlVjVPm6VH6akheW5Qk5YGpjc4OqmlIV07IJ1ujzBw WqqIC3/dJpdB4rnusCfV7E6L15lu4xOI12IFKX8WlMefIUOoKyYWe/ZeZnRBfonxRQ 4b4s40OiOBPgA== From: Kees Cook To: Bill Wendling Cc: Kees Cook , Andy Shevchenko , "Christophe Leroy (CS GROUP)" , =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , linuxppc-dev@lists.ozlabs.org, Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Shivaprasad G Bhat , Thorsten Blum , Steven Rostedt , nikitash.mariiaw@gmail.com, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: [PATCH v2 7/9] powerpc/papr_scm: Return the string length from the sysfs show functions Date: Fri, 18 Sep 2026 17:27:05 -0700 Message-Id: <20260919002714.4060307-7-kees@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20260919002658.stay.929-kees@kernel.org> References: <20260919002658.stay.929-kees@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Developer-Signature: v=1; a=openpgp-sha256; l=1655; i=kees@kernel.org; h=from:subject; bh=bM8pfQZ+WNZUIhOsBdyOBh8XaXJCdRjSK82ONfe5d+M=; b=owGbwMvMwCVmps19z/KJym7G02pJDFlrr91q4EzZaveH25A94nRu1Y5jMxliT9oIzu2cXTjz9 JlPP39rd5SyMIhxMciKKbIE2bnHuXi8bQ93n6sIM4eVCWQIAxenAEyEo42R4ediE7YbL1Y3Lbw4 OeOHcKbwygMm7Svur7ikccVfnLFgrhEjw5R7kbH2bSXNa2cXqrzpX6b/OYTvoNXjS17vJQrMFc0 mcAEA X-Developer-Key: i=kees@kernel.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 Content-Transfer-Encoding: 8bit perf_stats_show() and flags_show() build their output with a seq_buf and return seq_buf_used(), which may include the trailing NUL byte when the seq_buf has overflowed. Use seq_buf_strlen() instead. Build tested ARCH=powerpc ppc64_defconfig with GCC powerpc64-linux-gnu 16.1.0: arch/powerpc/platforms/pseries/papr_scm.o Assisted-by: LLM Reviewed-by: Andy Shevchenko Signed-off-by: Kees Cook --- Cc: "Christophe Leroy (CS GROUP)" Cc: "Uwe Kleine-König" Cc: Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Shivaprasad G Bhat Cc: Thorsten Blum --- arch/powerpc/platforms/pseries/papr_scm.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/platforms/pseries/papr_scm.c b/arch/powerpc/platforms/pseries/papr_scm.c index 75da96c08cdd..b03cfd8528f5 100644 --- a/arch/powerpc/platforms/pseries/papr_scm.c +++ b/arch/powerpc/platforms/pseries/papr_scm.c @@ -1108,7 +1108,7 @@ static ssize_t perf_stats_show(struct device *dev, free_stats: kfree(stats); - return rc ? rc : (ssize_t)seq_buf_used(&s); + return rc ?: (ssize_t)seq_buf_strlen(&s); } static DEVICE_ATTR_ADMIN_RO(perf_stats); @@ -1150,7 +1150,7 @@ static ssize_t flags_show(struct device *dev, if (seq_buf_used(&s)) seq_buf_printf(&s, "\n"); - return seq_buf_used(&s); + return seq_buf_strlen(&s); } DEVICE_ATTR_RO(flags); -- 2.34.1