Files
linux-stable-mirror/drivers
Harry Wentland ee9cfcf77a drm/amd/display: Fix NULL deref and buffer over-read in SDP debugfs
commit adf67034b1 upstream.

[Why & How]
dp_sdp_message_debugfs_write() dereferences connector->base.state->crtc
without checking for NULL. A connector can be connected but not bound to
any CRTC (e.g. after hot-plug before the next atomic commit), causing a
kernel crash when writing to the sdp_message debugfs node.

The function also ignores the user-provided size argument and always
passes 36 bytes to copy_from_user(), reading past the user buffer when
size < 36.

Fix both issues by:
- Returning -ENODEV when connector->base.state or state->crtc is NULL
- Clamping write_size to min(size, sizeof(data))

Fixes: c7ba3653e9 ("drm/amd/display: Generic SDP message access in amdgpu")
Assisted-by: Copilot:claude-opus-4.6
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Ray Wu <ray.wu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 6ab4c36a52)
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-19 13:21:39 +02:00
..
2026-06-01 17:29:22 +02:00
2026-06-19 13:21:38 +02:00
2026-06-19 13:21:39 +02:00
2026-01-19 13:12:07 +01:00