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 8063419885B; Wed, 5 Jun 2024 11:50:15 +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=1717588215; cv=none; b=tJotDGLEoeeTqFrV5pvGZz6gBlLqyplKrTWt43ArGZPpA4FwVIUtKeNL/Yh4jc9CK6tm+WaNY6jqwcpgAi/wm0nw5+FV/LO6Hf6HuphlXoCo33Ht+d8QPuvKz8KsiYLusy7h8VEx0i/YqH2Q2VlNRfn1tw4ECuVtth0Jc/+oKOA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717588215; c=relaxed/simple; bh=F7cpV+a+C7Mbpd4Oog7sdLoU5k2L8t8xst9Mf7jNOQc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=CkymNMycWoAqaNyJhVzFiHuFDzUB35RedBqzxDDlAywkOUgLP4gnCcRPusTIyWkebVu8pJK4b87QJi1uqDOe6NKTcXgxmMKVvzcNJdMRUP2C6Bea1+gHvVoeMSk+Pe9N30UQzZy00FiFpd+fnZRF4dkwCkdZUkLX2rMHuZd7lwo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jz3sn4f6; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="jz3sn4f6" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 909BCC4AF07; Wed, 5 Jun 2024 11:50:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1717588215; bh=F7cpV+a+C7Mbpd4Oog7sdLoU5k2L8t8xst9Mf7jNOQc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jz3sn4f6NJBNWErnpXXRXslCw3AzEvQ+DPaKcqtAx1CvCFuCaK6we4qHZX+Nf838u HlbmOUHzXl+HjAKOEMzCnRkXwNUW7+nFnTqRhHawsdIwhiTSsgS58NIPOIL1NtiG8h 7cgoUutJt9/8CEX8oJ3jiW7UqhpmDMOgDs8WPOrGbdRYUiiQ02p9y64d1uHQ28bRAM 0DXhFuZGW6bN/aMplomyNqse9JidLQW7SsMScWkm/IFHXxhtRbtCTgFyKdzYuKbZHR 3RT7VgXcnvo70Zr4OTZfeWBlWqPV3LXqlBVS9tij5EUN+EHHRcZjLO0VAiLMWSNXc7 VEtQbiJPd0BJQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Sicong Huang , Greg Kroah-Hartman , Sasha Levin , johan@kernel.org, greybus-dev@lists.linaro.org Subject: [PATCH AUTOSEL 6.9 20/28] greybus: Fix use-after-free bug in gb_interface_release due to race condition. Date: Wed, 5 Jun 2024 07:48:49 -0400 Message-ID: <20240605114927.2961639-20-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240605114927.2961639-1-sashal@kernel.org> References: <20240605114927.2961639-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.9.3 Content-Transfer-Encoding: 8bit From: Sicong Huang [ Upstream commit 5c9c5d7f26acc2c669c1dcf57d1bb43ee99220ce ] In gb_interface_create, &intf->mode_switch_completion is bound with gb_interface_mode_switch_work. Then it will be started by gb_interface_request_mode_switch. Here is the relevant code. if (!queue_work(system_long_wq, &intf->mode_switch_work)) { ... } If we call gb_interface_release to make cleanup, there may be an unfinished work. This function will call kfree to free the object "intf". However, if gb_interface_mode_switch_work is scheduled to run after kfree, it may cause use-after-free error as gb_interface_mode_switch_work will use the object "intf". The possible execution flow that may lead to the issue is as follows: CPU0 CPU1 | gb_interface_create | gb_interface_request_mode_switch gb_interface_release | kfree(intf) (free) | | gb_interface_mode_switch_work | mutex_lock(&intf->mutex) (use) Fix it by canceling the work before kfree. Signed-off-by: Sicong Huang Link: https://lore.kernel.org/r/20240416080313.92306-1-congei42@163.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/greybus/interface.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/greybus/interface.c b/drivers/greybus/interface.c index fd58a86b0888d..d022bfb5e95d7 100644 --- a/drivers/greybus/interface.c +++ b/drivers/greybus/interface.c @@ -693,6 +693,7 @@ static void gb_interface_release(struct device *dev) trace_gb_interface_release(intf); + cancel_work_sync(&intf->mode_switch_work); kfree(intf); } -- 2.43.0