From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) (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 A13E6472084 for ; Tue, 1 Sep 2026 09:31:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.72 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788255099; cv=none; b=VctOBWfcDz6Jom03mclfhGh5KRBnmX+A4mkSnxVN3yUekxaKZNQTyZH0SzFFhRXYHEFuNeGdMMN4QTD73HjEk7Aoi2aDybR0CrF9AH1csKcS0AZf7ZBNAisTsInmXXVWc723Obv8CzI3Zel0PYPlomgkotOhfRyFlWYfHunJjLI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788255099; c=relaxed/simple; bh=jl9D4HbYtt0iCvxNDHgV3gzFDkORtqHa3wmJR3iNSNo=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=b4aFg+35l7wu/sstyZRvfvkj9gdAafAYQOwa1TbW5C2BQBSMW7/iUsyyAJn13CGEOEZ2ze1RyuDTRYXxJkE8YzyyFffi+rN+G4CsCQ/3HB/OpGbgOWf38CNCUuTeYz4PkRfzVu4xIooodRLPJt/hXEibfNWJZ4gJNmvc2WjiugM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--aliceryhl.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=YgqCR5n0; arc=none smtp.client-ip=209.85.128.72 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--aliceryhl.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="YgqCR5n0" Received: by mail-wm1-f72.google.com with SMTP id 5b1f17b1804b1-49ccf17d3b0so16430125e9.3 for ; Tue, 01 Sep 2026 02:31:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1788255088; x=1788859888; 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=s/fiWQ63WImRaHU5MSJK0Js7QMO+oBpUYF5cl556nCw=; b=YgqCR5n09fBrW7zpDuji28fP8w1S3eHOxZzo4QVSz6U4fz1x+GnNUtF6rr74E2yD5H vsrdpoecqPHozyDmJyPWRVAIA51JS9tXUXRyzJttCyZEEK0dW0z4kUT+tN+ajxwhnrFg dITmEN/by07cVGJCqb/O0T7G7vlCIUq61hL/8LKR7Z7glwqCoPhnFrmFbR6zaorTs112 UNlVglqR+au9cWvX7sAbH8WqtrLwhmThapJvJUjwm5P+I1PGL1Vd70Fb7bN4ZwH+qDYZ O2Qc8gb0LeakJLqi91CHZgqqHFwthbt2gndvFAvGhdrKSrZ02RQcWCwJt8nU9CB7w3V4 npsA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788255088; x=1788859888; 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=s/fiWQ63WImRaHU5MSJK0Js7QMO+oBpUYF5cl556nCw=; b=B2LfL/1U37c/h6fxrcJWFpdHlo6LAJqebzh1fST4V0/14Ft/gHWKbBsadBHxEtPeML oFzQo6UhJ2WAewEaxIhiUetPB29XOonolpwUNIFWNF+4dgfRiOqPFRDX/Mqv/ZrgYD2X ospsliuIjnlr3IF10i7CX7hd1IeaGamzubt+Me+toti70PCR0Ubp/CShBO+zkn+4zLDR 0ei7+qgOGaIcH5ozWuR0JM+CDIoNPmMW6B0Pc88KdVh9GWhxBjnYtXUi3MKFb8URG38X ZJ+jQFv1+5XOiEzO4hLIukAj67ds9reoFat1/jAivZX65heJSJVK98tlrnsS0SrqIiCY lKBg== X-Forwarded-Encrypted: i=1; AHgh+RoqCYztLCjTbdKx1X8uifYFeh6bfEoYck/N7DNuimxTUUvIW6TwuBKOkRWXEl7yO6JJwZFcaOk=@vger.kernel.org X-Gm-Message-State: AFuF++m2BHhEMW822uymBgtEHUTjPDWUkW4XFDKdOrcbrRIEjNepEw0p Mf3Sz7cUeaUmTzRReVoarfSbri+gS1bLMDbqAD6+Y5l0VEGupHBZ8sH/H5v7f22aZ1R6D5M+pYy ZEOEWl27e9kOBcw0LTw== X-Received: from wmpo25.prod.google.com ([2002:a05:600c:3399:b0:499:610e:c4b7]) (user=aliceryhl job=prod-delivery.src-stubby-dispatcher) by 2002:a05:600c:1d99:b0:49c:cee0:e7c0 with SMTP id 5b1f17b1804b1-49cdc560282mr146000615e9.16.1788255088208; Tue, 01 Sep 2026 02:31:28 -0700 (PDT) Date: Tue, 1 Sep 2026 09:31:27 +0000 In-Reply-To: <20260901030419.470246-4-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> <20260901030419.470246-4-cmllamas@google.com> Message-ID: Subject: Re: [PATCH v2 3/5] binder: check vma->vm_start in binder_vma_close() From: Alice Ryhl To: Carlos Llamas Cc: Greg Kroah-Hartman , "Arve =?utf-8?B?SGrDuG5uZXbDpWc=?=" , Todd Kjos , Christian Brauner , kernel-team@android.com, linux-kernel@vger.kernel.org, Suren Baghdasaryan , stable@vger.kernel.org, Sashiko Content-Type: text/plain; charset="utf-8" On Tue, Sep 01, 2026 at 03:04:14AM +0000, Carlos Llamas wrote: > Certain operations like a failed mremap() might trigger vm_ops->close() > on temporary mappings. To avoid tearing-down the main binder mapping on > these, let's verify that the VMA matches the expected starting address. > > Cc: stable@vger.kernel.org > Fixes: 457b9a6f09f0 ("Staging: android: add binder driver") > Reported-by: Sashiko > Closes: https://sashiko.dev/#/patchset/20260831224145.169403-1-cmllamas%40google.com?part=1 > Signed-off-by: Carlos Llamas I don't quite understand this. You explicitly made sure mremap() can't happen to begin with, so when is this called? Alice