diff options
authorMatthew Wilcox <>2019-02-14 11:03:48 -0800
committerDave Airlie <>2019-02-15 13:08:08 +1000
commit69ef943dbc14b21987c79f8399ffea08f9a1b446 (patch)
parent7abbb35ba98ec52583b92898b2e37533f462d248 (diff)
drm: Use array_size() when creating leasedrm-fixes-2019-02-15-1
Passing an object_count of sufficient size will make object_count * 4 wrap around to be very small, then a later function will happily iterate off the end of the object_ids array. Using array_size() will saturate at SIZE_MAX, the kmalloc() will fail and we'll return an -ENOMEM to the norty userspace. Fixes: 62884cd386b8 ("drm: Add four ioctls for managing drm mode object leases [v7]") Signed-off-by: Matthew Wilcox <> Acked-by: Kees Cook <> Acked-by: Daniel Vetter <> Cc: <> # v4.15+ Signed-off-by: Dave Airlie <>
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/gpu/drm/drm_lease.c b/drivers/gpu/drm/drm_lease.c
index 99cba8ea5d82..5df1256618cc 100644
--- a/drivers/gpu/drm/drm_lease.c
+++ b/drivers/gpu/drm/drm_lease.c
@@ -528,7 +528,8 @@ int drm_mode_create_lease_ioctl(struct drm_device *dev,
object_count = cl->object_count;
- object_ids = memdup_user(u64_to_user_ptr(cl->object_ids), object_count * sizeof(__u32));
+ object_ids = memdup_user(u64_to_user_ptr(cl->object_ids),
+ array_size(object_count, sizeof(__u32)));
if (IS_ERR(object_ids))
return PTR_ERR(object_ids);