From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f182.google.com (mail-pf1-f182.google.com [209.85.210.182]) (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 7B3F52D63E8 for ; Wed, 6 May 2026 03:45:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778039146; cv=none; b=eeqUTLUGUniM4BHVc2AiDRUF/NbzvCvKQ3pZmekFqNKqJXZh95pu8xUPi9j4ydQQ8O5bQshNUTv9JUTquzmNE6PTdysz8rc8E3jj6Qh9ETo1+vkJoawK8az4/UtuXzEAsRcaxeSD2JhhDXflnmhp0xw2IKvEVQMPZciib0DLpm0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778039146; c=relaxed/simple; bh=e7MFWAvOrD6x55/XFyvjUmf1OBviZSxCrWEKFtCHq+o=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=STOMyjWc2jjzVYR6w6zx7KXmMw78e4vGhMgvljlJI9iwH3+VY4k26wZe5N9uMfSodXc11eTiMn0bSBJOglm0eVTiKgoVVtLsQta8hYoNAahcKOkUvQ/JN2dI9cDIo3LGtknBGsXtL4KZ6SATwbUFYXO+WbIEIl2D2bhbKjBVj6w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=l09R+GFm; arc=none smtp.client-ip=209.85.210.182 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=google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="l09R+GFm" Received: by mail-pf1-f182.google.com with SMTP id d2e1a72fcca58-8354461da74so1556886b3a.1 for ; Tue, 05 May 2026 20:45:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1778039144; x=1778643944; darn=lists.linux.dev; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=SjHOkaHu+NkO38S6EeZoMhD2GWUGazZfx6GKOrIeYZk=; b=l09R+GFm5BEQUXqeMPjig3fjUlbxXax7NIViHtFNPdn/J7vaHSd5tYXhvr5FR0lrLd Vcbo4bpUwsGv5oOW9AHkeeCiUXENAOMLyI5J+4QBqYUNaiSji3OF/FsJ62sfrCtsHep/ baLZpd430hFjPKX/VKajs19/ZurbKLWfag9DdG8rGkS1v86M9fLRYH/upBHn4uzUNrRo aWThXPnfijQSXcP7nXiOVsKP4IdtaFnM39UHj0CspucGRofwluOjVUkILpXKmm5/Ehh1 xLvSMxQ0PlfX7SLvjcSPv16VC3+dVxH6YJuM8yH1U/l6VA9zkbukSZk9M46FjLQDPxIL +raQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1778039144; x=1778643944; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=SjHOkaHu+NkO38S6EeZoMhD2GWUGazZfx6GKOrIeYZk=; b=nUP7aNqdIkwC9MHMr3mXMHLOv9U/ICotmCQ3+WBo1uzFES3nyUi1Lcy9dN01t5xOHu xeex1XC89BWugp2Tr8pYjt4ZHTiGJVt7IMe8/lDqMwiAY/qUxDYKXCR5w02LB3tHbJ7j 1Y3QSciJR7Q0B1Y7xzXcI/D07yUSeMmtpvcOlNmjBdIBrmBhDE6Bn4v6cL1AzNo+hgo4 vExIHDuVsSJlCZLNQpwTzr/PhzM5zHVTFshPuPAS7EHkiRZHGWEvFQbeO5+t2zt0gt6L O6IFixeu9mbhShY/usawb/mUA5AxZfCWeoffcX1V/xWe3KKm0FIoL2qZ9HjGNbxL7BOk CVjQ== X-Forwarded-Encrypted: i=1; AFNElJ9RO2XZZC0TK9bRRR2hNK5w2iJ9k241Cs8rS/HKP6mduX/oq6CWEsTtkHHFtB+EAHjMKToMtBNIftCmJseqUaY=@lists.linux.dev X-Gm-Message-State: AOJu0YwKsR/YxC9NQ50T1fDyai87gz0+Gj5L8CeTO77cpnVtAmOmoBUf RXCr66VkNSuBli2UV4uEt3/HP/8nlsVXuFHG+eJD4sZ0B1aOA2PBS9tUqg+vrx9epQ== X-Gm-Gg: AeBDiesCyT12vGGv0IPpCVqyMH1oBb8o5saJxyGty+ZGdNhVpemJhm2EfbCY9XUXReg YjKfPWe29F68LUjekMFJjZtUQR5XX6OcmkYJozEbYpzqiYN1+TnqRk18ydGEQVVZPwduQgYWtFv 8ATu9P4bfv5Gy04aUX/c8g0Rz4TePy5WE2C5mSJ8r8AlvL00HK+zDrwHAjBSHo0o9dKkiE7DCfN 9/R5figd8bZPXbXqU9lkFUrnyezhg96H26jAkmU5eKIeYhZLPKbEsYTkfAqpQCzmTeQ8aG3wQu5 QyKbRGKW0aLZzmWIy1YTt5zvV4WlmBIP3plFRkM+pQsDg8YIazTrfJtnrLoPMNsOP34/dVYtz0V ZifsBu02pYh1lkJL7WQ08Jyf/Datu6ehl5okNgL86jqLYNYbROODdPpdh/hRxQid7krcd5AyqtS tAmbQlrhgEshx0iEvVvd6wGcKB9g3rmmJ3ZMNxNgfLAMKLJYZg5oPzAf8sNL7o6YXZAehaoO5j1 wHLBw== X-Received: by 2002:a05:6a20:6a09:b0:398:d82c:ae6 with SMTP id adf61e73a8af0-3aa5a936bc4mr1494087637.31.1778039143093; Tue, 05 May 2026 20:45:43 -0700 (PDT) Received: from google.com (51.86.127.34.bc.googleusercontent.com. [34.127.86.51]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-c8242ba1bacsm607897a12.23.2026.05.05.20.45.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 05 May 2026 20:45:41 -0700 (PDT) Date: Wed, 6 May 2026 03:45:36 +0000 From: Benson Leung To: Andrei Kuchynski Cc: Lee Jones , Benson Leung , Sergey Senozhatsky , Guenter Roeck , Tzung-Bi Shih , Logan Gunthorpe , Greg Kroah-Hartman , chrome-platform@lists.linux.dev, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH] mfd: cros_ec: Delay dev_set_drvdata() until probe success Message-ID: References: <20260427131721.1165078-1-akuchynski@chromium.org> Precedence: bulk X-Mailing-List: chrome-platform@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="i1JlCb1XYyQceS4y" Content-Disposition: inline In-Reply-To: <20260427131721.1165078-1-akuchynski@chromium.org> --i1JlCb1XYyQceS4y Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi Andrei, On Mon, Apr 27, 2026 at 01:17:21PM +0000, Andrei Kuchynski wrote: > If ec_device_probe() fails, cros_ec_class_release releases memory for the > cros_ec_dev structure. However, because the drvdata was already set, > sub-drivers like cros_ec_typec can still retrieve the stale pointer via t= he > platform device. This leads to a use-after-free when cros_ec_typec attemp= ts > to access &typec->ec->ec->dev on a device that has already been released. > Move dev_set_drvdata() to ensure that the pointer is only made available > once all initialization steps have succeeded. >=20 > sysfs: cannot create duplicate filename '/class/chromeos/cros_ec' > Call trace: > sysfs_do_create_link_sd+0x94/0xdc > sysfs_create_link+0x30/0x44 > device_add_class_symlinks+0x90/0x13c > device_add+0xf0/0x50c > ec_device_probe+0x150/0x4f0 > platform_probe+0xa0/0xe0 > ... > BUG: KASAN: invalid-access in __memcpy+0x44/0x230 > Write at addr f5ffff809e2d33ac by task kworker/u32:5/125 > Pointer tag: [f5], memory tag: [fe] > Tainted : [W]=3DWARN, [O]=3DOOT_MODULE > Hardware name: Google Navi unprovisioned 0x7FFFFFFF/sku0 board/sku3 > Workqueue: events_unbound deferred_probe_work_func > Call trace: > __memcpy+0x44/0x230 > cros_ec_check_features+0x60/0xcc [cros_ec_proto] > cros_typec_probe+0xe8/0x6e0 [cros_ec_typec] > platform_probe+0xa0/0xe0 >=20 > Cc: stable@vger.kernel.org > Fixes: 1c1d152cc5ac ("platform/chrome: cros_ec_dev - utilize new cdev_dev= ice_add helper function") > Co-developed-by: Sergey Senozhatsky > Signed-off-by: Sergey Senozhatsky > Signed-off-by: Andrei Kuchynski Reviewed-by: Benson Leung > --- > drivers/mfd/cros_ec_dev.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) >=20 > diff --git a/drivers/mfd/cros_ec_dev.c b/drivers/mfd/cros_ec_dev.c > index 39430dd44e30c..56fb7cceafc6c 100644 > --- a/drivers/mfd/cros_ec_dev.c > +++ b/drivers/mfd/cros_ec_dev.c > @@ -195,7 +195,6 @@ static int ec_device_probe(struct platform_device *pd= ev) > if (!ec) > return retval; > =20 > - dev_set_drvdata(dev, ec); > ec->ec_dev =3D dev_get_drvdata(dev->parent); > ec->dev =3D dev; > ec->cmd_offset =3D ec_platform->cmd_offset; > @@ -237,6 +236,8 @@ static int ec_device_probe(struct platform_device *pd= ev) > if (retval) > goto failed; > =20 > + dev_set_drvdata(dev, ec); > + > /* check whether this EC is a sensor hub. */ > if (cros_ec_get_sensor_count(ec) > 0) { > retval =3D mfd_add_hotplug_devices(ec->dev, > --=20 > 2.54.0.rc2.544.gc7ae2d5bb8-goog >=20 --i1JlCb1XYyQceS4y Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQQCtZK6p/AktxXfkOlzbaomhzOwwgUCafq5YAAKCRBzbaomhzOw ws9gAP4o/Y97BIaEjbh6PIhp9H7uWtUiizV3OOo5ubeMh3h+UAEArrSpYxJLsUf7 ascjppNyslvTH/yfwtUT/0Tw00Qe1AI= =+yyJ -----END PGP SIGNATURE----- --i1JlCb1XYyQceS4y--