From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-183.mta0.migadu.com (out-183.mta0.migadu.com [91.218.175.183]) (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 AC00330BF79 for ; Tue, 27 Jan 2026 11:07:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.183 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769512048; cv=none; b=W9fqR+WJ7dbh/unMvldjAmq7EocGZaOHDFoSGJA7rdDklA6i4bEr3fTh9r4JrD4DpIjRVV2mWHcQsOQ/nSQx6E+37I9kK6Eh41QixrWn+vzVNWMgFtjkozRAjSlB7m5tU85L1CZsNZqWqCvPS40ItWd05FUgSUfL4vfxPYCDr/M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769512048; c=relaxed/simple; bh=p6ATcMNAqUp0P6a/xm/T027KUorW3R12cYhPE8T529s=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VG+eXANCu57l1U9BwyyLLpvVDvnAr7YN8iKwwElpSpiw4BW684njLBTUBpgq8Be8tC+2LXW3v9cfOrTBJuRuqXZvuOkSEwfjfcQIU+DjQaucucJ1V0Qa40DIDBGhKKrRv67wQ7JWiE/G4t8eWiQfTJyR4+MecBn3JrLERFqNnXU= 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=GUnq+62+; arc=none smtp.client-ip=91.218.175.183 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="GUnq+62+" 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=1769512044; 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: in-reply-to:in-reply-to:references:references; bh=nnKd7x/vUhOTzGd8FoCvZV6tIq7PhtSSkjGuWUY1hLg=; b=GUnq+62+JIvt2L6syHkyb4wlqFvKZ+plmGGr2LRmJ31JSFcdYZe8UNoVCUIGyMGFcOMizN 7RruA3EgntlZQH9DfgsHOnbyeNw47OlNL1IA1mw0t8llsJ6P2Tsrkjh6Bl5Bwcnni4SOQn stU/B0Bq56oLlp6dehK6ekQxRRewAFs= From: Thorsten Blum To: Alexander Shishkin , Maxime Coquelin , Alexandre Torgue Cc: Thorsten Blum , linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH RESEND 2/2] stm class: Replace kzalloc + copy_from_user with memdup_user_nul Date: Tue, 27 Jan 2026 12:06:53 +0100 Message-ID: <20260127110654.436657-2-thorsten.blum@linux.dev> In-Reply-To: <20260127110654.436657-1-thorsten.blum@linux.dev> References: <20260127110654.436657-1-thorsten.blum@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT Replace kzalloc() followed by copy_from_user() with memdup_user_nul() to simplify and improve stm_char_policy_set_ioctl(). Remove the obsolete comment. Signed-off-by: Thorsten Blum --- drivers/hwtracing/stm/core.c | 15 +++------------ 1 file changed, 3 insertions(+), 12 deletions(-) diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c index 5834f796e86b..335bcf749214 100644 --- a/drivers/hwtracing/stm/core.c +++ b/drivers/hwtracing/stm/core.c @@ -733,18 +733,9 @@ static int stm_char_policy_set_ioctl(struct stm_file *stmf, void __user *arg) if (size < sizeof(*id) || size >= PATH_MAX + sizeof(*id)) return -EINVAL; - /* - * size + 1 to make sure the .id string at the bottom is terminated, - * which is also why memdup_user() is not useful here - */ - id = kzalloc(size + 1, GFP_KERNEL); - if (!id) - return -ENOMEM; - - if (copy_from_user(id, arg, size)) { - ret = -EFAULT; - goto err_free; - } + id = memdup_user_nul(arg, size); + if (IS_ERR(id)) + return PTR_ERR(id); if (id->__reserved_0 || id->__reserved_1) goto err_free; -- Thorsten Blum GPG: 1D60 735E 8AEF 3BE4 73B6 9D84 7336 78FD 8DFE EAD4