[PATCH AUTOSEL 4.19 56/57] drm/amdgpu: fix integer overflow test in amdgpu_bo_list_create()

Sasha Levin
2018-11-04T14:04:52Z

From: Dan Carpenter <dan.carpenter@oracle.com>

[ Upstream commit ff30e9e8509cb877dc7cbc776b36c70f5bdd290f ]

We accidentally left out the size of the amdgpu_bo_list struct. It
could lead to memory corruption on 32 bit systems. You'd have to
pick the absolute maximum and set "num_entries == 59652323" then size
would wrap to 16 bytes.

Fixes: 920990cb080a ("drm/amdgpu: allocate the bo_list array after the list")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Reviewed-by: Bas Nieuwenhuizen <basni@chromium.org>
Signed-off-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
index d472a2c8399f..b80243d3972e 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
@@ -67,7 +67,8 @@ int amdgpu_bo_list_create(struct amdgpu_device *adev, struct drm_file *filp,
unsigned i;
int r;

- if (num_entries > SIZE_MAX / sizeof(struct amdgpu_bo_list_entry))
+ if (num_entries > (SIZE_MAX - sizeof(struct amdgpu_bo_list))
+ / sizeof(struct amdgpu_bo_list_entry))
return -EINVAL;

size = sizeof(struct amdgpu_bo_list);
--
2.17.1