drm/gud: don't keep a connector without a CRTC as connector_state

If the 'for_each_new_connector_in_state()' loop finishes without
hitting the break, connector_state is left pointing at the last
con

drm/gud: don't keep a connector without a CRTC as connector_state

If the 'for_each_new_connector_in_state()' loop finishes without
hitting the break, connector_state is left pointing at the last
connector visited, which has no CRTC, instead of
staying NULL.

That skips the "if (!connector_state)" fallback below the loop, which
looks up the active connector when the state contains none. The
function then carries on with a connector that is not driven.

Fix by resetting connector_state to NULL for each connector visited that
has no CRTC, so that it is NULL when none was found and the fallback runs.

Fixes: 40e1a70b4aed ("drm: Add GUD USB Display driver")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260902123254.36987-1-sajal2005gupta@gmail.com?part=1
Signed-off-by: Sajal Gupta <sajal2005gupta@gmail.com>
Acked-by: Ruben Wauters <rubenru09@aol.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Ruben Wauters <rubenru09@aol.com>
Link: https://patch.msgid.link/20260922084026.15481-1-sajal2005gupta@gmail.com

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drm/gud: fix out-of-bounds write in gud_plane_atomic_check()

The plane property loop uses req->properties[num_properties + i] as write
index while simultaneously incrementing `num_properties` inside

drm/gud: fix out-of-bounds write in gud_plane_atomic_check()

The plane property loop uses req->properties[num_properties + i] as write
index while simultaneously incrementing `num_properties` inside the loop.
At iteration i, num_properties has also incremented by i, so the write
is done at `initial_num_properties + 2*i`, skipping every other index and
advancing by 2 per iteration.

With just 2 connector and 32 plane properties the last write happens at
index 64, one slot past the end of the 64-slot (indices 0–63)
allocation. A USB device can trigger OOB by advertising the maximum
number of properties.

Fix by dropping the redundant `+ i`; num_properties is already the correct
running index, as gud_connector_fill_properties() fills the preceding
slots.

Fixes: 40e1a70b4aed ("drm: Add GUD USB Display driver")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260821071812.16500-1-sajal2005gupta%40gmail.com?part=1
Signed-off-by: Sajal Gupta <sajal2005gupta@gmail.com>
Cc: <stable@vger.kernel.org>
Acked-by: Ruben Wauters <rubenru09@aol.com>
Signed-off-by: Ruben Wauters <rubenru09@aol.com>
Link: https://patch.msgid.link/20260902123254.36987-1-sajal2005gupta@gmail.com

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drm/gud: Ignore damage clips in full update mode

When running in full update mode, previously small updates (such as
moving the mouse across the screen) would cause many full frames to be
generated.

drm/gud: Ignore damage clips in full update mode

When running in full update mode, previously small updates (such as
moving the mouse across the screen) would cause many full frames to be
generated. This would bog down the bus and lower the effective framerate
significantly - I was seeing a drop from 60 FPS to 2 FPS.

Set ignore_damage_clips in full update mode so the damage iterator
yields a single full-plane rectangle instead of one per clip.

Fixes: 73cfd166e045 ("drm/gud: Replace simple display pipe with DRM atomic helpers")
Cc: <stable@vger.kernel.org> # 6.18.x
Signed-off-by: Sophie D <patches@scd31.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Ruben Wauters <rubenru09@aol.com>
Signed-off-by: Ruben Wauters <rubenru09@aol.com>
Link: https://patch.msgid.link/20260910014910.8564-1-patches@scd31.com

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