From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f200.google.com (mail-pl1-f200.google.com [209.85.214.200]) (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 6550C41612A for ; Tue, 1 Sep 2026 03:04:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.200 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788231866; cv=none; b=YSUODcXe0wBoKR2Bu75ZrpsHieUFTbQ5KnLKA+fxcUz4cZArbQUXsG0p1PCNFr712V51qs/rvX2sxCgmN1106oCz4SqR9+OI0zEN9200JkGlrKmU8dmU8q33A+DaVg/H43jaVvkBN7iYZHlgUaJa6tBkzPGGJIXIz69lF5BXbOk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788231866; c=relaxed/simple; bh=ZVDmy6VjoBuiJ9n9p6Ad1YWPKaC9lxc9NZ2K2c+ucEM=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=Jwf3/cUoeh9kZdZCvTPKHIEfC29Y4EMM2bLIRJHz8A+460mdcx9fzaneYII2Jx9n59v6fs0r82M0gV0NdprmX+fG+mpUs1X7bkHtQvbEL1cDZmKDcHyX5AQHsmzOFd/vw0CIQ317UmoMVyssfVuH/jH4kDtnnVUMYUc+iy9paf8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--cmllamas.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=bhzRUiAt; arc=none smtp.client-ip=209.85.214.200 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--cmllamas.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="bhzRUiAt" Received: by mail-pl1-f200.google.com with SMTP id d9443c01a7336-2d7443e0f0bso14222085ad.1 for ; Mon, 31 Aug 2026 20:04:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1788231865; x=1788836665; darn=vger.kernel.org; h=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=8F8BdKyQbDU8LQ8WvhzelWDzD39wCf1FJtyBP4q/yWc=; b=bhzRUiAt8cG08SVMAC6Q9OqM3zOxPbhVYTK5Lbru9MADIq8Agqore1soqohOOrpo3y 1HlR05GOHy0V3QpzdsoXGQ5GpSxzwPxbJOtvNgoh4hFZ8LdR1Gf4MgkOOTQFA89qz4Hj ehO6XqlZP8MkLZvzNr+P3TXgekS3o7Y5Qt4DRj6oaCDUL/bTO3WPeVeRCq1VGZyrYsEq XT0STyKMqMc4zjrynImJUVOYhSDd7MOgFLxGO2qOSiyaSe10MuQnuuysROTx5AJZiJGy pk7upWX+f7ZZDqV/uwDqw/22PvXdMQ1+c8eR1ticskfzWof+xUFmtDEk6Z5oFbWAGZxX op8g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788231865; x=1788836665; h=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=8F8BdKyQbDU8LQ8WvhzelWDzD39wCf1FJtyBP4q/yWc=; b=TmnkGAY4K9MkddpbaH35jxhE6sfNgbN5Ko9grrmPCYOUMDEiioFYzHE8n4b/9n5nir RA+MWLet93P9t9n/qpHsH7U0Y39IARp2Mcg0Ax8QdtMu+IukqTTiM6oZ8b4HnyMSnEfY qn9OQfdp5zmaTLtXFGYROqLMQR23CiWt/9FJ/iAUgXZLxscWN8H4xO22oY3T8bNKFvE0 fsx4iNDscG7er6Xs3D0obY09rtImpTXTH84ywyTpEDNi1vpcHqetjYzXxcliiVj+TqTR H79vRlDN8aEowda4Z31CuhlBTomfoyK9qSi8SbWDSSiQCwjyFtlEPcIc4fySRieSy3n+ fMvA== X-Forwarded-Encrypted: i=1; AKwUvBxk3NUb4mkfN/bD5lUUT8ZMZmWIAf9EOOKsB3gwhsY2QmkmSRet6JYNPkXH8To55XvM/A39igA=@vger.kernel.org X-Gm-Message-State: AFuF++mpmOg0hlSQhhZNk8m7CeYccJlfeUesevcJMo1Vo70VaOx/1U+9 sKXO1NnOYl5WMulCcK/sXg/YAp65eg1O9pGpScbbtpbw83K5QzVKSDWcNxNNZx5UaSF+MPzOE4q CzzDk/GKdXrg5aw== X-Received: from dlbrs15.prod.google.com ([2002:a05:7022:f68f:b0:13d:1da6:85cf]) (user=cmllamas job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90a:1c08:b0:399:1b08:28de with SMTP id 98e67ed59e1d1-3991b082a7emr1620892a91.7.1788231864463; Mon, 31 Aug 2026 20:04:24 -0700 (PDT) Date: Tue, 1 Sep 2026 03:04:13 +0000 In-Reply-To: <20260901030419.470246-1-cmllamas@google.com> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260901030419.470246-1-cmllamas@google.com> X-Mailer: git-send-email 2.55.0.897.gb25b4bd76c-goog Message-ID: <20260901030419.470246-3-cmllamas@google.com> Subject: [PATCH v2 2/5] rust_binder: set VM_DONTEXPAND From: Carlos Llamas To: Greg Kroah-Hartman , "=?UTF-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?=" , Todd Kjos , Christian Brauner , Carlos Llamas , Alice Ryhl Cc: kernel-team@android.com, linux-kernel@vger.kernel.org, Suren Baghdasaryan , stable@vger.kernel.org, Sashiko Content-Type: text/plain; charset="UTF-8" Binder does not support expanding VMAs. It uses the original size to create its RangeAllocator during mmap() and expanding the VMA would only result in a wasted virtual range. Set the VM_DONTEXPAND flag to prevent the vma from being expanded via mremap(). Cc: stable@vger.kernel.org Fixes: eafedbc7c050 ("rust_binder: add Rust Binder driver") Reported-by: Sashiko Closes: https://sashiko.dev/#/patchset/20260831224145.169403-1-cmllamas%40google.com?part=1 Signed-off-by: Carlos Llamas --- drivers/android/binder/process.rs | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/android/binder/process.rs b/drivers/android/binder/process.rs index 5372bfbd93b3..9038f3d13cfd 100644 --- a/drivers/android/binder/process.rs +++ b/drivers/android/binder/process.rs @@ -1786,6 +1786,7 @@ pub(crate) fn mmap( vma.try_clear_maywrite().map_err(|_| EPERM)?; vma.set_dontcopy(); vma.set_mixedmap(); + vma.set_dontexpand(); // TODO: Set ops. We need to learn when the user unmaps so that we can stop using it. this.create_mapping(vma) -- 2.55.0.897.gb25b4bd76c-goog