[PATCH v2 0/2] drm/nouveau: avoid usage of list iterator after loop

From: Jakob Koschel
Date: Mon Mar 13 2023 - 09:55:17 EST


This patch set includes two instances where the list iterator variable
'pstate' is implicitly assumed to be valid after the iterator loop.
While in pratice that is most likely the case (if
'pstatei'/'args->v0.state' is <= the elements in clk->states), we should
explicitly only allow 'pstate' to always point to correct 'nvkm_pstate'
structs.

That allows catching potential bugs with WARN_ON(!pstate) that otherwise
would be completely undetectable.

It also helps the greater mission to hopefully move the list iterator
variable into the iterating macro directly [1].

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@xxxxxxxxxxxxxx/ [1]
Signed-off-by: Jakob Koschel <jkl820.git@xxxxxxxxx>
---
Changes in v2:
- convert BUG_ON() into WARN_ON()
- Link to v1: https://lore.kernel.org/r/20230301-drm-nouveau-avoid-iter-after-loop-v1-0-0702ec23f970@xxxxxxxxx

---
Jakob Koschel (2):
drm/nouveau/device: avoid usage of list iterator after loop
drm/nouveau/clk: avoid usage of list iterator after loop

drivers/gpu/drm/nouveau/nvkm/engine/device/ctrl.c | 11 ++++++++---
drivers/gpu/drm/nouveau/nvkm/subdev/clk/base.c | 10 +++++++---
2 files changed, 15 insertions(+), 6 deletions(-)
---
base-commit: c0927a7a5391f7d8e593e5e50ead7505a23cadf9
change-id: 20230301-drm-nouveau-avoid-iter-after-loop-4bff97166efa

Best regards,
--
Jakob Koschel <jkl820.git@xxxxxxxxx>