From nobody Mon Feb 9 06:29:02 2026 Received: from mail-yw1-f201.google.com (mail-yw1-f201.google.com [209.85.128.201]) (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 D92DF1AD415 for ; Tue, 24 Sep 2024 18:44:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727203453; cv=none; b=fTk31mCfLf48GcgIXHB2bJXE3bhIrfkHa51CkwtlSx1SNGhY8wbAfWfBwIWV+YEw9BUZ87OqO+TL6hsRrHZ/VYsTNDp28IrnMZlVPmdldCQ85+q8l6toQU3s73F3TWpAX0T9IvKf5ma67FXs47RouTGH/Ei5rQ0qLFkvNjKO0fA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727203453; c=relaxed/simple; bh=HZ1COR0YGONUxe6LALXOBsTQqR3jecbdCznCpBgsKV4=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=rFY5ibkWWNL25phwaskSPFtBmUq1jtcvqPN0voOlQ4bmycmz6b3+bsBbrNMd3b/CKF4SpA9f07n8kjLvxCdAT6Zh3NaIu7Vfjj7UOQLubkgGGtkXqMPXjS2sBMLIh+l+Ba7WBtpd0Xn3zCiEpLh7dfZ+BHYSrAz6vy3hNc8iFa8= 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=wybKm1ld; arc=none smtp.client-ip=209.85.128.201 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="wybKm1ld" Received: by mail-yw1-f201.google.com with SMTP id 00721157ae682-6e2146737ccso14405757b3.2 for ; Tue, 24 Sep 2024 11:44:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1727203451; x=1727808251; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=opL/u+rXDPzP8jgIWM68Kz10UL7QxmAwA+KsygDZ6JA=; b=wybKm1ldf4yJzCJhqH0kNEA+NV/mnTBqNVhZ706jT0BM0sJASAX+iBeY89/sxTECgu udmKoPJiwa5UmwGYXrQ2danBJ47N8F09djOIJ30UlbBAwUniNRi5PjwnaMjfxDo1AKiW 731+veTVkdqFs5zpoTOJRw0VIG2RaNNQ7bxH/YqYLZPihWdWtJrWXp3w5/zaz+3jbEm/ ERNDNYDjCAAC6ep9IA6OwbOidwv9NLg00mYcMqNWuL72uZLqsTL5oAHXQ8G3fZkxxzB4 omiwOYntqEobr+VcECAvAWN7WJvQkkEXVWO07uH+78yT3IJarDDhlKBmfNUNnGa9XiAD hQvg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1727203451; x=1727808251; h=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; bh=opL/u+rXDPzP8jgIWM68Kz10UL7QxmAwA+KsygDZ6JA=; b=jH1yEzpJAd/Uq5S2P1jaNieByTNPvF8cE5jxFeLnInYeZStA+EUCT58TKsu99vxMNG JbvdHnpkhCkrcIT8yPD2pDm+2UOnLwWY72cn7yekrVFZTWTaNYbbeCMLIZTIw8Z99r/Y PVGH5wiTSeVDzUzWhB1M3kQM408GozQYEAkqLPUzjb2co2+lFpQvbSF6EuPk5/t2Oq8R /GfoGaFkfQx0Bs1bOI7BKt/PSUUU9O22hIlvFI/Dv2FkmdxSj9HyHesmdRSskyB+jUR0 9Cl6eYpsAFd9v7mzsuQu6f+NCOGnbYPbg4J6ZRza1ZbqSLjWeGZBZTrO/31sm41Y+U/8 azgg== X-Gm-Message-State: AOJu0YxIua9w/GmPmqRZhA0TwuzkNyiC44pBrP0AcbK2+dPnKCA/wPh9 wGFcaq6q/PBNSdaNJt69ofTsQEIHZRN+uGcUZ0qWRqQO6TlVMExu4I/YLlMvN9Jo8BDMqfjFE3C g36K8ZAjLBQ== X-Google-Smtp-Source: AGHT+IHm0uPwL+BamoIvPtwKlIEqmPJHv0+Z7rowDrFzsw5n5EgUKWZ1MOEFlvHEOZosOFgTFgCJdSpj1QLADA== X-Received: from xllamas.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5070]) (user=cmllamas job=sendgmr) by 2002:a05:690c:2892:b0:648:fc8a:cd23 with SMTP id 00721157ae682-6e21d6e1f34mr31987b3.2.1727203450911; Tue, 24 Sep 2024 11:44:10 -0700 (PDT) Date: Tue, 24 Sep 2024 18:43:55 +0000 In-Reply-To: <20240924184401.76043-1-cmllamas@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240924184401.76043-1-cmllamas@google.com> X-Mailer: git-send-email 2.46.0.792.g87dc391469-goog Message-ID: <20240924184401.76043-4-cmllamas@google.com> Subject: [PATCH 3/4] binder: fix freeze UAF in binder_release_work() From: Carlos Llamas To: Greg Kroah-Hartman , "=?UTF-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?=" , Todd Kjos , Martijn Coenen , Joel Fernandes , Christian Brauner , Carlos Llamas , Suren Baghdasaryan , Yu-Ting Tseng Cc: linux-kernel@vger.kernel.org, kernel-team@android.com, Alice Ryhl , stable@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" When a binder reference is cleaned up, any freeze work queued in the associated process should also be removed. Otherwise, the reference is freed while its ref->freeze.work is still queued in proc->work leading to a use-after-free issue as shown by the following KASAN report: =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D BUG: KASAN: slab-use-after-free in binder_release_work+0x398/0x3d0 Read of size 8 at addr ffff31600ee91488 by task kworker/5:1/211 CPU: 5 UID: 0 PID: 211 Comm: kworker/5:1 Not tainted 6.11.0-rc7-00382-gfc= 6c92196396 #22 Hardware name: linux,dummy-virt (DT) Workqueue: events binder_deferred_func Call trace: binder_release_work+0x398/0x3d0 binder_deferred_func+0xb60/0x109c process_one_work+0x51c/0xbd4 worker_thread+0x608/0xee8 Allocated by task 703: __kmalloc_cache_noprof+0x130/0x280 binder_thread_write+0xdb4/0x42a0 binder_ioctl+0x18f0/0x25ac __arm64_sys_ioctl+0x124/0x190 invoke_syscall+0x6c/0x254 Freed by task 211: kfree+0xc4/0x230 binder_deferred_func+0xae8/0x109c process_one_work+0x51c/0xbd4 worker_thread+0x608/0xee8 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D This commit fixes the issue by ensuring any queued freeze work is removed when cleaning up a binder reference. Fixes: d579b04a52a1 ("binder: frozen notification") Cc: stable@vger.kernel.org Signed-off-by: Carlos Llamas Acked-by: Todd Kjos Reviewed-by: Alice Ryhl --- drivers/android/binder.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 8bca2de6fa24..d955135ee37a 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -1225,6 +1225,12 @@ static void binder_cleanup_ref_olocked(struct binder= _ref *ref) binder_dequeue_work(ref->proc, &ref->death->work); binder_stats_deleted(BINDER_STAT_DEATH); } + + if (ref->freeze) { + binder_dequeue_work(ref->proc, &ref->freeze->work); + binder_stats_deleted(BINDER_STAT_FREEZE); + } + binder_stats_deleted(BINDER_STAT_REF); } =20 --=20 2.46.0.792.g87dc391469-goog