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 70810238C1F for ; Tue, 22 Jul 2025 21:37:36 +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=1753220256; cv=none; b=FrRyGoEVVri3UwSL82wdw6hinb/Ti0bgug2djK7K4d0JyuJdhRQTiX7pQNi8k2GkeTT6eEi3pSJB/C45G30GkWE3v0opaBlFhGRdz44Syqi2xO2vSFT3+5EW8x9FqLBsdPWdI6z2xb+aqzfnHs+4g0JM7WSRRYxpO3B6H8zfoOs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753220256; c=relaxed/simple; bh=r68BlRkATGHtvKy1BUfT6GQJEYaYJZogOj0fm+tRIX0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=GMlrq73ltsgIozZx5JkS7WVTzjjZo/G4/1fYFx+DEtiOqi3eZ3OMqOCRgXESSMTNObUEkOjwYFxyijLZPvhiaJbquv4+pb9GfriPPA3K7r4zlzhTFNLsgAa/poas2JU5svTex7zKBf9mvh7rN5NtKxJKc4O8zeT9YIcX41CPJAU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=a3U46rpl; 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="a3U46rpl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 47D35C4CEEB; Tue, 22 Jul 2025 21:37:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753220256; bh=r68BlRkATGHtvKy1BUfT6GQJEYaYJZogOj0fm+tRIX0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=a3U46rplENcYoQv5FQhP3gnIIuJAyHWvTNTKulaMOtbdvWlSoUuVJifkrmXuNts// PEqR8F3iJy3GziELp8uPM3o0sB+z+V80FMinC71E+rzJdfYX6jdsljDlAQQQcVf3cO 6N0U3CE1uqsbu3IIkH217D3cWaIDoponnkv5Ow+ffoMi61ph1mbJLmdrejYiuz5PRN q/4lws65oSHQqnHnUyqdCKF4qyc5H0dbOSqKB4jGRc8h4NYD+STcq7bpu4lLszS7rx anyYRa12qwVdyapDQ61YDHfHh/oMKOVciumFEqbo0oZMSSwLi62W6B27giWBIONRAK 7U8v7ih4Pn6jQ== From: Sasha Levin To: stable@vger.kernel.org Cc: Ian Abbott , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH 6.6.y] comedi: comedi_test: Fix possible deletion of uninitialized timers Date: Tue, 22 Jul 2025 17:37:31 -0400 Message-Id: <20250722213731.980366-1-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <2025072153-splinter-buckshot-87f5@gregkh> References: <2025072153-splinter-buckshot-87f5@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Ian Abbott [ Upstream commit 1b98304c09a0192598d0767f1eb8c83d7e793091 ] In `waveform_common_attach()`, the two timers `&devpriv->ai_timer` and `&devpriv->ao_timer` are initialized after the allocation of the device private data by `comedi_alloc_devpriv()` and the subdevices by `comedi_alloc_subdevices()`. The function may return with an error between those function calls. In that case, `waveform_detach()` will be called by the Comedi core to clean up. The check that `waveform_detach()` uses to decide whether to delete the timers is incorrect. It only checks that the device private data was allocated, but that does not guarantee that the timers were initialized. It also needs to check that the subdevices were allocated. Fix it. Fixes: 73e0e4dfed4c ("staging: comedi: comedi_test: fix timer lock-up") Cc: stable@vger.kernel.org # 6.15+ Signed-off-by: Ian Abbott Link: https://lore.kernel.org/r/20250708130627.21743-1-abbotti@mev.co.uk Signed-off-by: Greg Kroah-Hartman [ replaced timer_delete_sync() calls with del_timer_sync() ] Signed-off-by: Sasha Levin --- drivers/comedi/drivers/comedi_test.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/comedi/drivers/comedi_test.c b/drivers/comedi/drivers/comedi_test.c index 05ae9122823f8..e713ef611434d 100644 --- a/drivers/comedi/drivers/comedi_test.c +++ b/drivers/comedi/drivers/comedi_test.c @@ -790,7 +790,7 @@ static void waveform_detach(struct comedi_device *dev) { struct waveform_private *devpriv = dev->private; - if (devpriv) { + if (devpriv && dev->n_subdevices) { del_timer_sync(&devpriv->ai_timer); del_timer_sync(&devpriv->ao_timer); } -- 2.39.5