public inbox for stable@vger.kernel.org
 help / color / mirror / Atom feed
From: Jeff Mahoney <jeffm@suse.com>
To: Wayne Lin <Wayne.Lin@amd.com>, dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org, David Airlie <airlied@gmail.com>,
	Daniel Vetter <daniel@ffwll.ch>, Jeff Mahoney <jeffm@suse.com>,
	stable@vger.kernel.org
Subject: [PATCH] drm/mst: Fix NULL pointer dereference in drm_dp_add_payload_part2 (again)
Date: Fri, 12 Apr 2024 20:22:52 -0400	[thread overview]
Message-ID: <20240413002252.30780-1-jeffm@suse.com> (raw)

Commit 54d217406afe (drm: use mgr->dev in drm_dbg_kms in
drm_dp_add_payload_part2) appears to have been accidentially reverted as
part of commit 5aa1dfcdf0a42 (drm/mst: Refactor the flow for payload
allocation/removement).

I've been seeing NULL pointer dereferences in drm_dp_add_payload_part2
due to state->dev being NULL in the debug message printed if the payload
allocation has failed.

This commit restores mgr->dev to avoid the Oops.

Fixes: 5aa1dfcdf0a42 ("drm/mst: Refactor the flow for payload allocation/removement")
Cc: stable@vger.kernel.org
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
---
 drivers/gpu/drm/display/drm_dp_mst_topology.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c
index 03d528209426..3dc966f25c0c 100644
--- a/drivers/gpu/drm/display/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c
@@ -3437,7 +3437,7 @@ int drm_dp_add_payload_part2(struct drm_dp_mst_topology_mgr *mgr,
 
 	/* Skip failed payloads */
 	if (payload->payload_allocation_status != DRM_DP_MST_PAYLOAD_ALLOCATION_DFP) {
-		drm_dbg_kms(state->dev, "Part 1 of payload creation for %s failed, skipping part 2\n",
+		drm_dbg_kms(mgr->dev, "Part 1 of payload creation for %s failed, skipping part 2\n",
 			    payload->port->connector->name);
 		return -EIO;
 	}
-- 
2.44.0


             reply	other threads:[~2024-04-13  0:32 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-04-13  0:22 Jeff Mahoney [this message]
2024-04-13  0:57 ` [PATCH] drm/mst: Fix NULL pointer dereference in drm_dp_add_payload_part2 (again) Jeff Mahoney
2024-04-15  2:53   ` Lin, Wayne

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=20240413002252.30780-1-jeffm@suse.com \
    --to=jeffm@suse.com \
    --cc=Wayne.Lin@amd.com \
    --cc=airlied@gmail.com \
    --cc=daniel@ffwll.ch \
    --cc=dri-devel@lists.freedesktop.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=stable@vger.kernel.org \
    /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