linux-kernel - [PATCH 4.9 12/14] dmaengine: at_xdma: handle errors of at_xdmac_alloc

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20220711090535.887370745@linuxfoundation.org>
Date:   Mon, 11 Jul 2022 11:06:31 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Michael Walle <michael@...le.cc>,
        Vinod Koul <vkoul@...nel.org>
Subject: [PATCH 4.9 12/14] dmaengine: at_xdma: handle errors of at_xdmac_alloc_desc() correctly

From: Michael Walle <michael@...le.cc>

commit 3770d92bd5237d686e49da7b2fb86f53ee6ed259 upstream.

It seems that it is valid to have less than the requested number of
descriptors. But what is not valid and leads to subsequent errors is to
have zero descriptors. In that case, abort the probing.

Fixes: e1f7c9eee707 ("dmaengine: at_xdmac: creation of the atmel eXtended DMA Controller driver")
Signed-off-by: Michael Walle <michael@...le.cc>
Link: https://lore.kernel.org/r/20220526135111.1470926-1-michael@walle.cc
Signed-off-by: Vinod Koul <vkoul@...nel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/dma/at_xdmac.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/drivers/dma/at_xdmac.c
+++ b/drivers/dma/at_xdmac.c
@@ -1806,6 +1806,11 @@ static int at_xdmac_alloc_chan_resources
 	for (i = 0; i < init_nr_desc_per_channel; i++) {
 		desc = at_xdmac_alloc_desc(chan, GFP_ATOMIC);
 		if (!desc) {
+			if (i == 0) {
+				dev_warn(chan2dev(chan),
+					 "can't allocate any descriptors\n");
+				return -EIO;
+			}
 			dev_warn(chan2dev(chan),
 				"only %d descriptors have been allocated\n", i);
 			break;