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 763C54C74 for ; Mon, 14 Nov 2022 13:08:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C4274C433D6; Mon, 14 Nov 2022 13:08:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1668431310; bh=qL8QyZBMdKYvqS3/ujRcEC/QUg20EACA3V2/uwAqNr4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ve66lLRsMcw1LwmO1YxVjmUFehvdjfyRSrS0tNHS3hunS5dXmJrdZWJ3h29bKnLIV So376PK2zEerGb+sHB6BIkdeXFw9OV+fxlGYWyXig6x20xnVs/4LmYfjqPVzAUpTnv QwWFmoO8EdPKJgk3tTOze0gFxtSFqJhjswMqhy2Y= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Peter Rosin , Tudor Ambarus , Nicolas Ferre , Vinod Koul Subject: [PATCH 6.0 179/190] dmaengine: at_hdmac: Protect atchan->status with the channel lock Date: Mon, 14 Nov 2022 13:46:43 +0100 Message-Id: <20221114124506.710170519@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221114124458.806324402@linuxfoundation.org> References: <20221114124458.806324402@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Tudor Ambarus commit 6e5ad28d16f082efeae3d0bd2e31f24bed218019 upstream. Now that the complete callback call was removed from device_terminate_all(), we can protect the atchan->status with the channel lock. The atomic bitops on atchan->status do not substitute proper locking on the status, as one could still modify the status after the lock was dropped in atc_terminate_all() but before the atomic bitops were executed. Fixes: 078a6506141a ("dmaengine: at_hdmac: Fix deadlocks") Reported-by: Peter Rosin Signed-off-by: Tudor Ambarus Cc: stable@vger.kernel.org Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/ Acked-by: Nicolas Ferre Link: https://lore.kernel.org/r/20221025090306.297886-1-tudor.ambarus@microchip.com Link: https://lore.kernel.org/r/20221025090306.297886-7-tudor.ambarus@microchip.com Signed-off-by: Vinod Koul Signed-off-by: Greg Kroah-Hartman --- drivers/dma/at_hdmac.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/dma/at_hdmac.c +++ b/drivers/dma/at_hdmac.c @@ -1460,12 +1460,12 @@ static int atc_terminate_all(struct dma_ list_splice_tail_init(&atchan->queue, &atchan->free_list); list_splice_tail_init(&atchan->active_list, &atchan->free_list); - spin_unlock_irqrestore(&atchan->lock, flags); - clear_bit(ATC_IS_PAUSED, &atchan->status); /* if channel dedicated to cyclic operations, free it */ clear_bit(ATC_IS_CYCLIC, &atchan->status); + spin_unlock_irqrestore(&atchan->lock, flags); + return 0; }