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 ACA7A4A4410 for ; Tue, 1 Sep 2026 20:53:04 +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=1788295986; cv=none; b=JmssjA7bMJV4djfZTjQrtYkxValVknLwSrbkeZrqHmh6ZCA4bTOP/rnM2MKhy6A3HlKzQURx5JP1sN6idsTvvcUImAUiQkQFlG+h75ZHQJqcpSFAsoSXfcwOuY1JBOYjH0QZV4f4XKfs9MYrSFjmeyfrwhYu+w5FxW0YD2ddneU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788295986; c=relaxed/simple; bh=QlZ8bwAY9neKKHezVtvtUAl90mGSvbr/T2WPNJJtduo=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=r9y5IzPurDJQkOYrxNCAvYzBFyZQ4tSx5Z4Lbi4TJiPxXsccCLxV+O/3s8x7StMp5+h6g0AIIyh8NY/D1p6uzZBL4RV+QOUCz377ovtIJXhCkeqBVGhQDRvpJRcg2CSJMv8FaBoXznqaJ55/SUgkJgeWnzURVlUjb95uJ34MGus= 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=FYqTJLOz; 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="FYqTJLOz" Received: by mail-pl1-f200.google.com with SMTP id d9443c01a7336-2ccb687f82eso2979345ad.3 for ; Tue, 01 Sep 2026 13:53:04 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1788295984; x=1788900784; 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=EyvdbyrwWKUxEUT3K6aHYWOVvt2Ms0Td9F6k6Xd72tY=; b=FYqTJLOzU27ADUxg6lvT0ymOoh99oi1suhtDCJo42vITNZ1LofNuIaDIJvzDikSYkl THb/2EJhodntsntoB9hduUrNffL/1jKcSaBcD1xSlSm5V9sIDf2WkxjIejMd9Ckjg7kE eV+bmOUpeSw6riC9MQFzSjmsDZ5tu1R7cJOWg5+NitxuTdJDT+pu3Eq2rYSfFo+2etLG +8uk7mn+lAAQn5R6QcjUIE4xrq5o6FJqqgJSzOftOFIqhYmOZBUUwlPLSg/FcYsldrIs 1CIumiU/i4G/mVpW/mbIh+BzvDeIkXfmVeDrfmfp5x3wYrKj5iFJZQZTFPB56/0Hz5OZ fy9A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788295984; x=1788900784; 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=EyvdbyrwWKUxEUT3K6aHYWOVvt2Ms0Td9F6k6Xd72tY=; b=aWYEFC2PsNGVKesUFt4+6x9dvxG/IMnJnVk0nr+epj+Hvd+lMDE9RRAn6qfolgzlT8 lOC8BrGaaUIPjuHP3IKq5vUz0y6afBfjD4NX1+MPJiRQRPToFgEFjTRCK9akqYDKqJHH 1kw+qnz3ITM50l5XsQ7s+DWNRLBp95pLXuPPBUTGg+Ysr6jXhgWw8d6qVbruytc/T3cI YpMIY9h5f1/NRdT19obbqCyYdmBv3uVkoxtPJApmaOnrdHfJ1AzZAP4uheewaF2iEBM/ 7oVNwMbQQWK3EVlgV5TMBjd5TXJM+gXdw3r53ZtiFcnKQDoxUAevFpr2WA6T/IagOlEA T9jA== X-Forwarded-Encrypted: i=1; AKwUvBwe6kpCz2lJTFaDVzGx1HVdylztycmY+P9Yjl2lA2EtJUuI0l55bCV0b2iZctBa+TWR6JP8qBrodJlfMj4=@vger.kernel.org X-Gm-Message-State: AFuF++mC+rZAoE7ikB+Vid2Tan+Q+fxqx/+Upd9Ihf5GBrU5QYok5fAJ fXtY0wSyZw4jTyv+HfLsMvAI/jlXe7q3nLAXegElabiy2hJ7nkBpu84GS4Uc8bd3PHQfII4QVCK MeE1B8VuBfAAPpQ== X-Received: from dybnj33.prod.google.com ([2002:a05:7300:d0a1:b0:32e:56c:c1dd]) (user=cmllamas job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:5745:b0:38e:fea2:df53 with SMTP id 98e67ed59e1d1-39ae8219104mr1343490a91.4.1788295983615; Tue, 01 Sep 2026 13:53:03 -0700 (PDT) Date: Tue, 1 Sep 2026 20:52:47 +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: <20260901205250.1638304-8-cmllamas@google.com> Subject: [PATCH v4 7/7] rust_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 , Benno Lossin , Gary Guo Cc: kernel-team@android.com, linux-kernel@vger.kernel.org, Suren Baghdasaryan , stable@vger.kernel.org, Sashiko , "open list:RUST [PIN-INIT]:Keyword:bpin-initb|pin_initb|PinInit" Content-Type: text/plain; charset="UTF-8" Binder does not support mremap() as it caches the mapping address in Inner::vma_addr. 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: eafedbc7c050 ("rust_binder: add Rust 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/page_range.rs | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/android/binder/page_range.rs b/drivers/android/binder/page_range.rs index d260b009c184..c6247ba03313 100644 --- a/drivers/android/binder/page_range.rs +++ b/drivers/android/binder/page_range.rs @@ -148,9 +148,14 @@ pub(crate) struct ShrinkablePageRange { EINVAL.to_errno() } +unsafe extern "C" fn binder_mremap(_: *mut bindings::vm_area_struct) -> c_int { + EINVAL.to_errno() +} + static BINDER_VM_OPS: AssertSync = { let ops = bindings::vm_operations_struct { may_split: Some(binder_vma_may_split), + mremap: Some(binder_mremap), ..pin_init::zeroed() }; AssertSync(ops) -- 2.55.0.966.g6673acef38-goog