On 10/11/2023 2:20 PM, Jani Nikula wrote:
On Wed, 11 Oct 2023, Nirmoy Das <nirmoy.das@xxxxxxxxx> wrote:
If measure_breadcrumb_dw() returns an error and bce isn't created,
this commit ensures that intel_engine_destroy_pinned_context()
is not called with a NULL bce.
So it's a potential NULL pointer dereference, not use after free like
the subject says. Please fix the subject.
ah right. I will resend.
Thanks,
Nirmoy
BR,
Jani.
Fixes: b35274993680 ("drm/i915: Create a kernel context for GGTT updates")
Cc: Oak Zeng <oak.zeng@xxxxxxxxx>
Cc: Andi Shyti <andi.shyti@xxxxxxxxxxxxxxx>
Signed-off-by: Nirmoy Das <nirmoy.das@xxxxxxxxx>
---
drivers/gpu/drm/i915/gt/intel_engine_cs.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index 179d9546865b..4a11219e560e 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -1491,7 +1491,8 @@ static int engine_init_common(struct intel_engine_cs *engine)
return 0;
err_bce_context:
- intel_engine_destroy_pinned_context(bce);
+ if (bce)
+ intel_engine_destroy_pinned_context(bce);
err_ce_context:
intel_engine_destroy_pinned_context(ce);
return ret;
