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 1B17428688A for ; Tue, 22 Jul 2025 21:45:06 +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=1753220707; cv=none; b=EloUBv/YWhx+9ZA3POYivykQsv3qgijaHO53FYUbU4LDRdAnocpUGPWCz95oaDmY40ieuiqwMhQszOwsOb25WfbMyEvQm6N8CAcHMUpJqaBD1PbueDSPbw6HQ+1wmLfEyF0NfwupzINwAz7hboS9inMvSoKlk6Lt0Q2a8iaFOL0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753220707; c=relaxed/simple; bh=zbNk8C/UQcIDtO8uLawdB2ZCHiTKynSjS+BM5kU29sw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=fq4R+f5y1wvnvg6nSxbN+Y0FQ/FGBvrZaxJrvVBT7BEc0ScsGg6MU/ArkS2SCOncMtKF3ajKBLy/uGlWtODZRE4/te790kem6frN3GLqz8K+Thy/p0jGbxSsGUaMLiRlX30hQ1XuwvIioYLu9Q47kvDuun5BTMXSp9XFW2oT7Is= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DfSBq7qo; 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="DfSBq7qo" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8D58DC4CEEB; Tue, 22 Jul 2025 21:45:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753220706; bh=zbNk8C/UQcIDtO8uLawdB2ZCHiTKynSjS+BM5kU29sw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DfSBq7qouHw3m4FG7OAdoZBvzWSDEcKfhHMeyGzR1ZG1E/IEsEh31Qgn60Dpt7KPa x/8IhhbbnfGqmK8Qz+XUPYtimbQuXJWE2LzCzMgrdPFM+GELo8SsEP4Mg15njVrrby 8t7OdmkNf1ZWdhyZCmom3LGI2OA7zkwKHVv/E2sCWZ/Ek0uaUcwwF5nH84QaaoHwjT XrFJVclXQP4JmWtUQCt49PVqsxq1Jk69L4qERxAfOAIKKmf7Y0U5iIDa39way4np1L rQOWqbgE+5ryLDmS72SDRdH7qgG6V+acf5r0IE/TANmwpsE7XFrHmA91odPkjf7NLP QAHupfvtz0DiA== From: Sasha Levin To: stable@vger.kernel.org Cc: Ian Abbott , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH 5.15.y] comedi: comedi_test: Fix possible deletion of uninitialized timers Date: Tue, 22 Jul 2025 17:45:01 -0400 Message-Id: <20250722214501.981060-1-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <2025072155-catering-series-cf00@gregkh> References: <2025072155-catering-series-cf00@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 [ changed del_timer_sync() calls to timer_delete_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 bea9a3adf08c8..f5199474c0e93 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