From 2bbe6ab2be53858507f11f99f856846d04765ae3 Mon Sep 17 00:00:00 2001 From: Luben Tuikov Date: Wed, 22 Nov 2023 23:58:53 -0500 Subject: drm/sched: Fix bounds limiting when given a malformed entity MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If we're given a malformed entity in drm_sched_entity_init()--shouldn't happen, but we verify--with out-of-bounds priority value, we set it to an allowed value. Fix the expression which sets this limit. Signed-off-by: Luben Tuikov Fixes: 56e449603f0ac5 ("drm/sched: Convert the GPU scheduler to variable number of run-queues") Link: https://patchwork.freedesktop.org/patch/msgid/20231123122422.167832-2-ltuikov89@gmail.com Reviewed-by: Christian König Link: https://lore.kernel.org/r/dbb91dbe-ef77-4d79-aaf9-2adb171c1d7a@amd.com --- drivers/gpu/drm/scheduler/sched_entity.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c index 4d42b1e4daa6..ee645d38e98d 100644 --- a/drivers/gpu/drm/scheduler/sched_entity.c +++ b/drivers/gpu/drm/scheduler/sched_entity.c @@ -81,12 +81,15 @@ int drm_sched_entity_init(struct drm_sched_entity *entity, */ pr_warn("%s: called with uninitialized scheduler\n", __func__); } else if (num_sched_list) { - /* The "priority" of an entity cannot exceed the number - * of run-queues of a scheduler. + /* The "priority" of an entity cannot exceed the number of run-queues of a + * scheduler. Protect against num_rqs being 0, by converting to signed. */ - if (entity->priority >= sched_list[0]->num_rqs) - entity->priority = max_t(u32, sched_list[0]->num_rqs, - DRM_SCHED_PRIORITY_MIN); + if (entity->priority >= sched_list[0]->num_rqs) { + drm_err(sched_list[0], "entity with out-of-bounds priority:%u num_rqs:%u\n", + entity->priority, sched_list[0]->num_rqs); + entity->priority = max_t(s32, (s32) sched_list[0]->num_rqs - 1, + (s32) DRM_SCHED_PRIORITY_MIN); + } entity->rq = sched_list[0]->sched_rq[entity->priority]; } -- cgit