From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f72.google.com (mail-pj1-f72.google.com [209.85.216.72]) (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 4F1454A3F2A for ; Tue, 1 Sep 2026 20:52:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.72 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788295979; cv=none; b=KIpYtsHdvOSHHae/kgBwlOt1Wfkm/RhakuVgVRZfRUeGPLN3KF9tZVPXo0SrsB0VNh8XL6pewxFOcmy147BNVD/4pO+/JjlTPNwcch4WI2RnwQTZj6k18WwedqepGdWTs/U2SZp4N9Pe307Uc6WbcWM1oBTruGrJ/qoazob4BVI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788295979; c=relaxed/simple; bh=qDxPPBiVzVIZg0bueYBv9GJ3dcl74Eqh6LmL3sW7by4=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=NbV65+LDwPK2922Q/2utGAXL9DmRr0icY11etdLVfCxY6GMRXMrZhRFV+euSaNwXZajLM4i8EN457/3wQKMaxxu/X2P0WQDyUuid8ohUaxkkocM2OFODFOLezPD2HXgqOZTMse6RItAaMvm5pQWDrwrIrT4LSGfrHMJzFbptktQ= 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=uZzhFoVv; arc=none smtp.client-ip=209.85.216.72 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="uZzhFoVv" Received: by mail-pj1-f72.google.com with SMTP id 98e67ed59e1d1-396b9ef3070so448761a91.3 for ; Tue, 01 Sep 2026 13:52:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1788295977; x=1788900777; 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=B4b9RJf/EoA9UAqTMJZs0pdFOLSykyAl2dSQSlyCXCk=; b=uZzhFoVvpFCQobtS2UZP/oJw6haDPgYW9kzWBA+S3a95dxlXmftJOubUvKjx/NmYDc CBvtwOQ7j9FJENsql8oqdMmdugkkY89Axo/B+CFYOx8kTF2YvQo7XhyRUIt8LPiu0nO/ e0kz+cAZpYcnS7+lbeVoqxf6qgjgxdb3ltVY4vDXr4f40Tqf5vrnUAi7SK3dA5G3DAdd Wx0ShhkxXDyte5R9NInT8KIGesb5ihZcWgZ7dBTGvUVVg3mWc8SAUT1TRLESp4tbsuZh HAXvSgdqE8ug4v5O2cS5hS4jJWAEcNZY/tBv6K3yhMyNYS6IWFjiDJEbsQ0R1tgxM5a0 SJWQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788295977; x=1788900777; 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=B4b9RJf/EoA9UAqTMJZs0pdFOLSykyAl2dSQSlyCXCk=; b=OMyWj1tRiELadBVkIQ7liyG41XZrTf5tvUdtGx4/i27Bz7cWJSnmBZsvfLBW8uHq0D 9Nm25acAZ9CTav9wQC5l5h5f8N2krKhHyF+7hN3ekHFIDzIokY1k84fuV4VZhG5sFnOQ n1zOQNT+5xnv+t4WyuOQ/hRKXcWdU6PI0Nr4kkpdtqJN4h2BA8khL9zSk5uNQxvHdYem a1615RGJMrnm0Mucstjy33KBzYhoL1U0H2SJe/cNYtCLU1XlZ/8zncSdyWDk60h0ztKB pJM7o5UYVPBoErOkTG1Fr5O0dRsd9Bj7UK1W8DzX2JKIic0zRIeyNm3RCkxpV87ZylGG T3ig== X-Forwarded-Encrypted: i=1; AKwUvBwA5dzVnQefTPwsfV/IYBiiIix0wpzF7VtbWTvfZV+BaERIu9127RDzv6gfZ31MhC5cmiLl46tf8gxcMks=@vger.kernel.org X-Gm-Message-State: AFuF++l9p+GNmJ0yzJeVpPFlBkKjgHRwMP7iz19kvS4KXr69UQOas0Cp /1mdylI4USDx6tJ0wa45HPxFHaKN6WhkjxUiEStAEqIokeiNFGJO+jt2IU/db6zTywZYYlatZEk dSYcpkJTOO4Xt2A== X-Received: from dltt5.prod.google.com ([2002:a05:701a:c965:b0:141:a317:d828]) (user=cmllamas job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:3903:b0:398:ba96:1afd with SMTP id 98e67ed59e1d1-39907bbe018mr15277088a91.8.1788295977354; Tue, 01 Sep 2026 13:52:57 -0700 (PDT) Date: Tue, 1 Sep 2026 20:52:42 +0000 In-Reply-To: <20260901205250.1638304-1-cmllamas@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260901205250.1638304-1-cmllamas@google.com> X-Mailer: git-send-email 2.55.0.966.g6673acef38-goog Message-ID: <20260901205250.1638304-3-cmllamas@google.com> Subject: [PATCH v4 2/7] 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@google.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) -- 2.55.0.966.g6673acef38-goog