[PATCH 4.19 187/639] drm/etnaviv: potential NULL dereference

From: Greg Kroah-Hartman
Date: Fri Jan 24 2020 - 06:09:21 EST


From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ Upstream commit 9e05352340d3a3e68c144136db9810b26ebb88c3 ]

The etnaviv_gem_prime_get_sg_table() is supposed to return error
pointers. Otherwise it can lead to a NULL dereference when it's called
from drm_gem_map_dma_buf().

Fixes: 5f4a4a73f437 ("drm/etnaviv: fix gem_prime_get_sg_table to return new SG table")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Reviewed-by: Christian Gmeiner <christian.gmeiner@xxxxxxxxx>
Signed-off-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
index 0566171f8df22..f21529e635e3d 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c
@@ -15,7 +15,7 @@ struct sg_table *etnaviv_gem_prime_get_sg_table(struct drm_gem_object *obj)
int npages = obj->size >> PAGE_SHIFT;

if (WARN_ON(!etnaviv_obj->pages)) /* should have already pinned! */
- return NULL;
+ return ERR_PTR(-EINVAL);

return drm_prime_pages_to_sg(etnaviv_obj->pages, npages);
}
--
2.20.1