From: Yonatan Maman <Ymaman@xxxxxxxxxx>
A copy push command might fail, causing `migrate_to_ram` to return a
dirty HIGH_USER page to the user.
This exposes a security vulnerability in the nouveau driver. To prevent
memory leaks in `migrate_to_ram` upon a copy error, allocate a zero
page for the destination page.
Fixes: 5be73b690875 ("drm/nouveau/dmem: device memory helpers for SVM")
Signed-off-by: Yonatan Maman <Ymaman@xxxxxxxxxx>
Signed-off-by: Gal Shalom <GalShalom@xxxxxxxxxx>
Reviewed-by: Ben Skeggs <bskeggs@xxxxxxxxxx>
---
drivers/gpu/drm/nouveau/nouveau_dmem.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/nouveau/nouveau_dmem.c b/drivers/gpu/drm/nouveau/nouveau_dmem.c
index 6fb65b01d778..097bd3af0719 100644
--- a/drivers/gpu/drm/nouveau/nouveau_dmem.c
+++ b/drivers/gpu/drm/nouveau/nouveau_dmem.c
@@ -193,7 +193,7 @@ static vm_fault_t nouveau_dmem_migrate_to_ram(struct vm_fault *vmf)
if (!spage || !(src & MIGRATE_PFN_MIGRATE))
goto done;
- dpage = alloc_page_vma(GFP_HIGHUSER, vmf->vma, vmf->address);
+ dpage = alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO, vmf->vma, vmf->address);
if (!dpage)
goto done;
--
2.34.1
