From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DAF193AE18C; Mon, 23 Mar 2026 14:02:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774274561; cv=none; b=KTS1Ptp0KoMMNkAK3HPkwtJXRQGrKuXzFOawY9ixWYKLMVXWOORUyuLVmTl8ImsoBenGteCiwBtMCBnzejxZQa3AMZoH7UCp9QVIKl9yKO3m0wULg7UyxkDTOSlR/y5ZsKK/8dt50O39tl7HrZvhM6bEEAP9pAmKAI2k64jF/i0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774274561; c=relaxed/simple; bh=1HkOMo5b2BHLK8kYUBIM+D/M2pfcjX0jf20tZ8t9Abs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=OUr2L3fRUpu4MOpZ02rcyAY5YmYZpMgu89QTN4C9U3msl0pK2KbOq4QMrgnbUMoTdv14ATzbpolTnG0k9ut8dRS7x/ZX9Ay9HGDeSJYWtL6A+RsHRfyyIENCslGdaBnddHzGn77Y3UuFNhxvegjOZIihw0spPAmcNMhd9aRnju0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zvTKEhzQ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="zvTKEhzQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5DAF5C2BCB7; Mon, 23 Mar 2026 14:02:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1774274561; bh=1HkOMo5b2BHLK8kYUBIM+D/M2pfcjX0jf20tZ8t9Abs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zvTKEhzQGUhpuT4TnlQ/fR2lTMsJMdYmQiaWrwCB2ahawUc1H8ILpyojVrCbreOcZ VdZGpPkjBA6AqqPmfX9in6cQXC/E+9uGJhZnVnVJlr19orGCo+4z/1per2jz92VHl/ qqvOFKAhnWXX8jfEPYs4DCnAbpVcdzOX9o95wHPs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dingisoul , Dave Jiang , Ira Weiny Subject: [PATCH 6.18 007/212] nvdimm/bus: Fix potential use after free in asynchronous initialization Date: Mon, 23 Mar 2026 14:43:48 +0100 Message-ID: <20260323134504.001502710@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260323134503.770111826@linuxfoundation.org> References: <20260323134503.770111826@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ira Weiny commit a8aec14230322ed8f1e8042b6d656c1631d41163 upstream. Dingisoul with KASAN reports a use after free if device_add() fails in nd_async_device_register(). Commit b6eae0f61db2 ("libnvdimm: Hold reference on parent while scheduling async init") correctly added a reference on the parent device to be held until asynchronous initialization was complete. However, if device_add() results in an allocation failure the ref count of the device drops to 0 prior to the parent pointer being accessed. Thus resulting in use after free. The bug bot AI correctly identified the fix. Save a reference to the parent pointer to be used to drop the parent reference regardless of the outcome of device_add(). Reported-by: Dingisoul Closes: http://lore.kernel.org/8855544b-be9e-4153-aa55-0bc328b13733@gmail.com Fixes: b6eae0f61db2 ("libnvdimm: Hold reference on parent while scheduling async init") Cc: stable@vger.kernel.org Reviewed-by: Dave Jiang Link: https://patch.msgid.link/20260306-fix-uaf-async-init-v1-1-a28fd7526723@intel.com Signed-off-by: Ira Weiny Signed-off-by: Greg Kroah-Hartman --- drivers/nvdimm/bus.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/nvdimm/bus.c +++ b/drivers/nvdimm/bus.c @@ -486,14 +486,15 @@ EXPORT_SYMBOL_GPL(nd_synchronize); static void nd_async_device_register(void *d, async_cookie_t cookie) { struct device *dev = d; + struct device *parent = dev->parent; if (device_add(dev) != 0) { dev_err(dev, "%s: failed\n", __func__); put_device(dev); } put_device(dev); - if (dev->parent) - put_device(dev->parent); + if (parent) + put_device(parent); } static void nd_async_device_unregister(void *d, async_cookie_t cookie)