From: Robin Murphy <robin.murphy@arm.com>
To: thierry.reding@gmail.com, mperttunen@nvidia.com
Cc: linux-tegra@vger.kernel.org, dri-devel@lists.freedesktop.org
Subject: [PATCH] drm/tegra: vic: Fix DMA API misuse
Date: Wed, 24 Nov 2021 19:10:07 +0000 [thread overview]
Message-ID: <2703882439344010e33bf21ecd63cf9e5e6dc00d.1637781007.git.robin.murphy@arm.com> (raw)
Upon failure, dma_alloc_coherent() returns NULL. If that does happen,
passing some uninitialised stack contents to dma_mapping_error() - which
belongs to a different API in the first place - has precious little
chance of detecting it.
Also include the correct header, because the fragile transitive
inclusion currently providing it is going to break soon.
Fixes: 20e7dce255e9 ("drm/tegra: Remove memory allocation from Falcon library")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
It also doesn't appear to handle failure of the tegra_drm_alloc() path
either, but that's a loose thread I have no desire to pull on... ;)
---
drivers/gpu/drm/tegra/vic.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/tegra/vic.c b/drivers/gpu/drm/tegra/vic.c
index c02010ff2b7f..da4af5371991 100644
--- a/drivers/gpu/drm/tegra/vic.c
+++ b/drivers/gpu/drm/tegra/vic.c
@@ -5,6 +5,7 @@
#include <linux/clk.h>
#include <linux/delay.h>
+#include <linux/dma-mapping.h>
#include <linux/host1x.h>
#include <linux/iommu.h>
#include <linux/module.h>
@@ -232,10 +233,8 @@ static int vic_load_firmware(struct vic *vic)
if (!client->group) {
virt = dma_alloc_coherent(vic->dev, size, &iova, GFP_KERNEL);
-
- err = dma_mapping_error(vic->dev, iova);
- if (err < 0)
- return err;
+ if (!virt)
+ return -ENOMEM;
} else {
virt = tegra_drm_alloc(tegra, size, &iova);
}
--
2.28.0.dirty
reply other threads:[~2021-11-24 19:10 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=2703882439344010e33bf21ecd63cf9e5e6dc00d.1637781007.git.robin.murphy@arm.com \
--to=robin.murphy@arm.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=linux-tegra@vger.kernel.org \
--cc=mperttunen@nvidia.com \
--cc=thierry.reding@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).