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 867B230ACE6; Mon, 13 Apr 2026 16:27:59 +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=1776097679; cv=none; b=rxveL9Fg92nQtdYIjtQct07/NftCUrEV9/Fwonsr6WexywGSb4amR3UKUZMQr51hanwLMFsg9z66/OMLHADNDfxKXsNOXhVXTwru36Ly8AcoL85X9wUZZVAD3Lr9InXUX7sSIAhSgDPAgw35urWYj/omW1s79BakFyalDSIwsko= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776097679; c=relaxed/simple; bh=8txmi2MCyvqx4Evu5bDVHEbSxR5oFI0jznIf586Yqn4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=HJzEfFbSFVB9ScwYvuqnydzK7N0ink77eMdnomkZQKIwvtzLqn4EuYLFI66UFJm9NAfEVVSsPxFdU6pAyC9DAkp1CBzBXdld9aKVIgxP8xYiZMQK50ZeZwIn0kzK4j3bOLhbZ76tDpU1oLB7r2RRLHD0xCpVRfBuDt2+ieoyXek= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=NDoWuand; 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="NDoWuand" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1BA32C2BCAF; Mon, 13 Apr 2026 16:27:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1776097679; bh=8txmi2MCyvqx4Evu5bDVHEbSxR5oFI0jznIf586Yqn4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NDoWuandJ4vZfm/yMHehmH4Nswiv4ANmvB00lzZaygsy5ldf3cLhLzliTlPRc09rk 5DRnhzu/h7f66/Wlo4RoHYJ65WEEmh5Kx5l4/N+DhgQc++L2O7dFdA7KG7UxIJsc3t yqs9Mv+jaOBHdQhxwwm7GCIwACSesg8FiD81B/fA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dingisoul , Dave Jiang , Ira Weiny Subject: [PATCH 5.15 198/570] nvdimm/bus: Fix potential use after free in asynchronous initialization Date: Mon, 13 Apr 2026 17:55:29 +0200 Message-ID: <20260413155837.875795642@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260413155830.386096114@linuxfoundation.org> References: <20260413155830.386096114@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-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 @@ -492,14 +492,15 @@ 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)