From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f197.google.com (mail-pl1-f197.google.com [209.85.214.197]) (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 4692C4A4401 for ; Tue, 1 Sep 2026 20:53:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.197 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788295984; cv=none; b=HYFmRI04xRa/Yr4WOAfnGillK1veL9dtbYeQ5Ia7WvcPUvKBntDucX4ElYmLMibFdp5f5cpU4nLoPxGrGhM2VrSDcjalX+urUrtIU56ovGooCEOwNLP/tmSaZSbqLq0Im94iP4MV7HNIpw/LnVIt8pZa4tRtktYSTn7HR3RDN4c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788295984; c=relaxed/simple; bh=/gMq7w6xSnPLzuoQSCSqsUxsfxg4kXXouj2VF8DdqoQ=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=skY+TQ88bpiBYUkG2MYfBoq3mWeUSTbYIS4XwLu3OMs7Z/xoxLoo9GO+DBigf1iPAEKhrAdqbI/IjQwfTXuYNXLu5LSgQuDHv/JJVF6NTR724Lm3bGYjwCZAvY4HaeLj+onC9R9eyKUdhbjrxQPpYklLDvbxtK+ncuzhV6WH7VY= 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=f8931WG3; arc=none smtp.client-ip=209.85.214.197 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="f8931WG3" Received: by mail-pl1-f197.google.com with SMTP id d9443c01a7336-2d55d8cd938so3913495ad.1 for ; Tue, 01 Sep 2026 13:53:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1788295982; x=1788900782; 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=11XYeOadEK/aHTk3U1zKkiikckIvd/a0F9zap2SHnBg=; b=f8931WG3klFJfJqJonM45DVGjKgCo1+14iY8P4AU3WAZ5oi0FYAj28QlcFG8DdOEbL HKtqp/9fY92mdpcmsDyr33+FhjyHrZq+95mesrXaYx7Y9wDcszQ+9c0fu9F10UZhf+e2 rnelhqtQnxqTw/ZghSM+1di8Ob7xh2nYJ3YH9RkpeEl3P4YfApnDyVZxGZpx/G8+INC4 kvTy9NL1p9prRMoGRj6cQw3FZvdjzk7pQ6DoE9rmwThNEB0jFmpLLRWElzPiRVtHm1F/ RIeOPPX2rWhKKUmc1KL9yG20ZIMx578ShIPiQBvFnE0JIcn9QhMEp4awqpUv4vzjW1qo lt5w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788295982; x=1788900782; 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=11XYeOadEK/aHTk3U1zKkiikckIvd/a0F9zap2SHnBg=; b=mRWd+WVRU0gfV07jRTozExkZelPlKg8VQEkAkLnEMWT4kM8+SsWbxLZXwai5puNwDn RtslNJhJgLD7s+Ecyq5oouPiD5jkIjo4MDgRYLHBFOPEM9xMUzjXuITJ8MWpEGqAmYH2 IKtR7HVtF2LXqeiRf7LiSqA7RtfKmdc5zJV3fk93XCrDbTCFHeOfX0tG6ITyzi9IpT3i DX3EmA/XYZV62S1vSh+76K90zOIzQiAMWOiQpRKsr9ea/M0IqQiRXan/oU+XrXl0s7AI GBpifoHYMT+IP/o2hw6i3zGgslVRFSc3PE+XlaOwYWD/kGp4M/V3SC0bXXr4lCExCXgw kMug== X-Forwarded-Encrypted: i=1; AKwUvBxG6c9KWpAoCeT3Dfk3FMMhGFuChsTmp48RcR/0O+QoVh14wTShgYxX2bpGSLXe8NB9ebp2gLk=@vger.kernel.org X-Gm-Message-State: AFuF++l3iyP9/zOV9zjhPXhUktKPb3t4KrVyap4SGMWcRcM3y4iICVBy xrlY26OAXl+qWNPnbhA8WC1wYBdOyD74Ba3s9q8FyD9gUQxtHA16cRc+b76VsJt8Or7ouMaCobK VAov12dk4v4UhSg== X-Received: from dycrm6.prod.google.com ([2002:a05:693c:2a06:b0:328:58f9:d18]) (user=cmllamas job=prod-delivery.src-stubby-dispatcher) by 2002:a17:902:e74f:b0:2c6:90ec:f601 with SMTP id d9443c01a7336-2dae5e17d6emr11628295ad.8.1788295982264; Tue, 01 Sep 2026 13:53:02 -0700 (PDT) Date: Tue, 1 Sep 2026 20:52:46 +0000 In-Reply-To: <20260901205250.1638304-1-cmllamas@google.com> Precedence: bulk X-Mailing-List: stable@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: <20260901205250.1638304-7-cmllamas@google.com> Subject: [PATCH v4 6/7] binder: reject mremap() 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 mremap() as it caches the mapping address in alloc->vm_start. Moving the mapping breaks the IPC communication for the process and can temporarily leak pages during a shrinker reclaim. Fix this by explicitly rejecting the .mremap() operation. Cc: stable@vger.kernel.org Fixes: 457b9a6f09f0 ("Staging: android: add binder driver") Reported-by: Sashiko Closes: https://sashiko.dev/#/patchset/20260813193433.3318288-1-surenb@google.com?part=2 Signed-off-by: Carlos Llamas --- drivers/android/binder.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 3d359490436e..290ccfde624d 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -6040,11 +6040,17 @@ static int binder_vma_may_split(struct vm_area_struct *vma, unsigned long addr) return -EINVAL; } +static int binder_mremap(struct vm_area_struct *vma) +{ + return -EINVAL; +} + static const struct vm_operations_struct binder_vm_ops = { .open = binder_vma_open, .close = binder_vma_close, .fault = binder_vm_fault, .may_split = binder_vma_may_split, + .mremap = binder_mremap, }; static int binder_mmap(struct file *filp, struct vm_area_struct *vma) -- 2.55.0.966.g6673acef38-goog