From 788568fad4015406fa84fc86cefbef7c470c7c1f Mon Sep 17 00:00:00 2001 From: John Harrison Date: Wed, 2 Aug 2023 11:49:40 -0700 Subject: [PATCH] drm/i915/guc: Fix potential null pointer deref in GuC 'steal id' test It was noticed that if the very first 'stealing' request failed to create for some reason then the 'steal all ids' loop would immediately exit with 'last' still being NULL. The test would attempt to continue but using a null pointer. Fix that by aborting the test if it fails to create any requests at all. Signed-off-by: John Harrison Reviewed-by: Andi Shyti Link: https://patchwork.freedesktop.org/patch/msgid/20230802184940.911753-1-John.C.Harrison@Intel.com --- drivers/gpu/drm/i915/gt/uc/selftest_guc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/uc/selftest_guc.c b/drivers/gpu/drm/i915/gt/uc/selftest_guc.c index 1fd760539f77..bfb72143566f 100644 --- a/drivers/gpu/drm/i915/gt/uc/selftest_guc.c +++ b/drivers/gpu/drm/i915/gt/uc/selftest_guc.c @@ -204,9 +204,9 @@ static int intel_guc_steal_guc_ids(void *arg) if (IS_ERR(rq)) { ret = PTR_ERR(rq); rq = NULL; - if (ret != -EAGAIN) { - guc_err(guc, "Failed to create request %d: %pe\n", - context_index, ERR_PTR(ret)); + if ((ret != -EAGAIN) || !last) { + guc_err(guc, "Failed to create %srequest %d: %pe\n", + last ? "" : "first ", context_index, ERR_PTR(ret)); goto err_spin_rq; } } else { -- 2.11.0