From nobody Sun Oct 5 00:09:24 2025 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 6652929BDB8; Mon, 11 Aug 2025 17:25:13 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754933114; cv=none; b=jV8f4+wNWc78enIhYCJod/1ODDyk+zPibjnMCmEWQz2CYO1innAlLWu2irnHyMjuf0sV8DSWI7DBWBn5kZ1A1/4z6hehfqawy4PZLAuTUnjVXC4lZKkfzBHlUpXnH3dHYbzdQNmBstmM6VneYF9+ZQZdZLgaJhezh3JmAOW31Kg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754933114; c=relaxed/simple; bh=lvhkMu0W1b5OC5e9sXMMahIDxfFt5PSt4ywN015JGAo=; h=Date:From:To:Subject:Cc:In-Reply-To:References:MIME-Version: Message-ID:Content-Type; b=Ju5HAEXEFVs8QJHegO/vejNm5aGUd2S3ZqYuTY2NpEUKbLmg6YVRMiel1GFEVt4PnfNiMsDdBH62AaT+CTo4vQKmRJtZTZZiSJRuzJxs7593mGy3NoKo4AS5pRDTHiG2q23LudtZpxrzIyAyXLgYBybxHLPxUyMh+Q4qdQSZYUE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=Ll2i+Ebo; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=q9+7FIYv; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="Ll2i+Ebo"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="q9+7FIYv" Date: Mon, 11 Aug 2025 15:58:01 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1754933111; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=eicc9bv7E8hw8eiH/Xiu7qBfBTipp6bu/QoYdC/hMDU=; b=Ll2i+Ebo2Lb5AOqf/R12xnnuYKrfQIn0U14py/nhpLCWtL+pmdPS7CGllxcSDbBk/kmUOR NCq/dOmp5gZi8iTUbL9uFfUHYQH83V5GQvNF1tVdNVFGVC/+oWkicumCD92tEEjNBaHwBr HqQkVSlhd7WTodiNlfwkKRAlVqLc380BAkkHQ/NYErmlv2ZpvHI8OWZ4MTbvlVmV3c3LYT dGFgteDaxh4CVf3XcaJedAg8z6BEkLr4FmLCO6YF3BIzs6Vl5WD0vUpwr7k58ZBbcFJN5G vzu9Dw6uQVhLeIn/ykCNXhaPYSLoceW2bOadhA7dqnsdq3dbUzpgOGk8iIyLKw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1754933111; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=eicc9bv7E8hw8eiH/Xiu7qBfBTipp6bu/QoYdC/hMDU=; b=q9+7FIYvqWxZNaL3T+Eak4sUeZNlVfK4n4bU6jMtw1adDE02TIpjrve75IW0zrSd/YKaEV 6QZ5aFRZClw9gTCw== From: "tip-bot2 for Waiman Long" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: locking/urgent] futex: Use user_write_access_begin/_end() in futex_put_value() Cc: Waiman Long , Thomas Gleixner , stable@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20250811141147.322261-1-longman@redhat.com> References: <20250811141147.322261-1-longman@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <175492788185.1420.501184708577751287.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the locking/urgent branch of tip: Commit-ID: dfb36e4a8db0cd56f92d4cb445f54e85a9b40897 Gitweb: https://git.kernel.org/tip/dfb36e4a8db0cd56f92d4cb445f54e85a= 9b40897 Author: Waiman Long AuthorDate: Mon, 11 Aug 2025 10:11:47 -04:00 Committer: Thomas Gleixner CommitterDate: Mon, 11 Aug 2025 17:53:21 +02:00 futex: Use user_write_access_begin/_end() in futex_put_value() Commit cec199c5e39b ("futex: Implement FUTEX2_NUMA") introduced the futex_put_value() helper to write a value to the given user address. However, it uses user_read_access_begin() before the write. For architectures that differentiate between read and write accesses, like PowerPC, futex_put_value() fails with -EFAULT. Fix that by using the user_write_access_begin/user_write_access_end() pair instead. Fixes: cec199c5e39b ("futex: Implement FUTEX2_NUMA") Signed-off-by: Waiman Long Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20250811141147.322261-1-longman@redhat.com --- kernel/futex/futex.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h index c74eac5..2cd5709 100644 --- a/kernel/futex/futex.h +++ b/kernel/futex/futex.h @@ -319,13 +319,13 @@ static __always_inline int futex_put_value(u32 val, u= 32 __user *to) { if (can_do_masked_user_access()) to =3D masked_user_access_begin(to); - else if (!user_read_access_begin(to, sizeof(*to))) + else if (!user_write_access_begin(to, sizeof(*to))) return -EFAULT; unsafe_put_user(val, to, Efault); - user_read_access_end(); + user_write_access_end(); return 0; Efault: - user_read_access_end(); + user_write_access_end(); return -EFAULT; } =20