drm/i915/gvt: fix off-by-one comparison of ring_id

Browse source

The ring_id maximum boundary is being compared using the > operator
instead of >=, leading to an off-by-one error and an out of bounds
write into array vgpu->hws_pga[].  Fix this by simply using the
correct comparison operator. Also re-work another comparison that
uses the comparison > I915_NUM_ENGINES - 1 to use the >= idiom using
to keep this consistent in this code.

Detected by CoverityScan, CID#1462404 ("Out-of-bounds write")

Fixes: a2ae95af96 ("drm/i915/gvt: update CSB and CSB write pointer in virtual HWSP")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

...

This commit is contained in:

Colin Ian King 2017-12-04 17:21:06 +00:00 • committed by Zhenyu Wang

parent f745e9cc7e

commit 8e60b7f195

1 changed files with 2 additions and 2 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

4

drivers/gpu/drm/i915/gvt/handlers.c

View file