From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from extorris.mess.org (extorris.mess.org [92.243.27.206]) (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 E29474DB575; Wed, 29 Jul 2026 15:23:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=92.243.27.206 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785338601; cv=none; b=KtXQpdZp/hu29scVCfeVDwrK0tI7s0m9LcX6y8DTWXpKLUp/mhlo3mLs1cF9F91I9Xr35cPn7ViytP6IG1Hb44J5Ul7IMg5v/mzrnJmOHNeKO4fxcip1E7eKIheLMiwlXKqNPRRFhw9l5UpCiIHe8GR7SGJcbZ5D32zOtK/CTIo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785338601; c=relaxed/simple; bh=xyBUi8ODCZ/afB0pcLqTLdSJP3AHZ3pkcnfLTF/XvQ0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=jbWon6SuJcxAj0K93bUBhpZ11aBRLc6YnA3cX9boQNp0HLWhggeJTxDJr4OnFay+V4ILmU+GNyXb0tamMi7LQdhS6QCX7AKcrfae0MyI+aaY6VHEj12EgLn8Eu7E8nfL/Uc5xD3l45/vH5HHfIFxgXxtQi/wETZsZ65PimaFd3Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=mess.org; spf=pass smtp.mailfrom=mess.org; dkim=pass (2048-bit key) header.d=mess.org header.i=@mess.org header.b=Qu6Hfxkp; dkim=pass (2048-bit key) header.d=mess.org header.i=@mess.org header.b=Fe4cCiXD; arc=none smtp.client-ip=92.243.27.206 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=mess.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mess.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mess.org header.i=@mess.org header.b="Qu6Hfxkp"; dkim=pass (2048-bit key) header.d=mess.org header.i=@mess.org header.b="Fe4cCiXD" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=mess.org; s=2020; t=1785338598; bh=xyBUi8ODCZ/afB0pcLqTLdSJP3AHZ3pkcnfLTF/XvQ0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Qu6HfxkpDces+Yicwsvtv5Hsykfrb3FhGLKVULi4TpK4Q99jzxAtLNg2c9LMWDQD0 vB02eeD8kvTNAhv5CmhBV9hmURcVeUPcUo2gc+OSB0ILTJ7TvZHQeoiCRftH1Ag+Yd Go8xrSd6iLb33RFMjotYqs3xPel7Xn4tlZp7l/E772vPEhjUx4q7B4N3ww09GgOm6i t2KVFMgOJx7p3CatZjsZPKJs1cqNdN0lH2nY2UZtZfmjQGkdMIpAhPryN1l9DJx1X1 gbhw5bs3wLw/zU7TmHVTIwVXC2SxVcFuZf63JEN/bdkt5sgr+kY9+Us2SJrhPjg8ML zSQAxnZhq6t6Q== Received: by extorris.mess.org (Postfix, from userid 1004) id ABA8D4253E; Wed, 29 Jul 2026 16:23:18 +0100 (BST) X-Spam-Level: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=mess.org; s=2020; t=1785338597; bh=xyBUi8ODCZ/afB0pcLqTLdSJP3AHZ3pkcnfLTF/XvQ0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Fe4cCiXDySaBFkplLn7JshvEf+6MUuaCM0CLsLdtcG7tBTR4ebh4I+4KV/NdDz26L /CV5k7tAAJwl4ggzxjoEOHGrqcL2BX+YI0Mz2r/3ELkGHv2lNWdRFdC9fGBV2/GcIG nxudmoa1CnEzwXc+RRPvp9lq51/LfHwS3ViK5o8dqcXfIWTNSuFJWwcJodsrZ4ReW0 55ly7bLx3nKhOWvLyoNFgBzIQcvDGKWiEZbolxzJRoB+3noVSrDbIugrXkn4CM3k1N t0E4NcUBgRX7dyOioGLo7Z0GPUXKB844p7s6f3jmBC44Vu7iwL+ZDnRa4d/smKxhUO or6VL4qnByjhg== Received: from maru.local (unknown [62.232.99.130]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by extorris.mess.org (Postfix) with ESMTPSA id 553D842534; Wed, 29 Jul 2026 16:23:17 +0100 (BST) From: Sean Young To: linux-media@vger.kernel.org, Sean Young , Mauro Carvalho Chehab , Patrice Chotard , Hans Verkuil Cc: stable@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5 14/15] media: rc: Use after free in ir_raw_event_handle() Date: Wed, 29 Jul 2026 16:22:52 +0100 Message-ID: X-Mailer: git-send-email 2.55.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit If rc_unregister_device() is called while IR is being processed, then ir_raw_event_handle() could call wake_up_process(dev->raw->thread) after kthread_stop(dev->raw->thread). Avoid use after free by using get_task_struct(). Fixes: dccc0c3ddf8f ("media: rc: fix race between unregister and urb/irq callbacks") Signed-off-by: Sean Young Cc: stable@vger.kernel.org --- drivers/media/rc/rc-ir-raw.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/media/rc/rc-ir-raw.c b/drivers/media/rc/rc-ir-raw.c index 46c50f423798..86de1b26731d 100644 --- a/drivers/media/rc/rc-ir-raw.c +++ b/drivers/media/rc/rc-ir-raw.c @@ -630,8 +630,13 @@ int ir_raw_event_register(struct rc_dev *dev) void ir_raw_event_free(struct rc_dev *dev) { - kfree(dev->raw); - dev->raw = NULL; + if (dev->raw) { + timer_delete_sync(&dev->raw->edge_handle); + if (dev->raw->thread) + put_task_struct(dev->raw->thread); + kfree(dev->raw); + dev->raw = NULL; + } } void ir_raw_event_unregister(struct rc_dev *dev) @@ -641,6 +646,13 @@ void ir_raw_event_unregister(struct rc_dev *dev) if (!dev || !dev->raw) return; + /* + * After ir_raw_event_unregister() is called, an sync + * call to ir_raw_event_handle() can still arrive. This function + * may call wake_up_process(dev->raw->thread). Ensure this memory + * is not freed by kthread_stop(). + */ + get_task_struct(dev->raw->thread); kthread_stop(dev->raw->thread); timer_delete_sync(&dev->raw->edge_handle); -- 2.55.0