From: Ma Ke <make_ruc2021@163.com>
Date: Fri, 13 Oct 2023 01:53:43 +0000 (+0800)
Subject: drm/amdgpu/vkms: fix a possible null pointer dereference
X-Git-Tag: v5.15.140~257
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=eaa03ea366c85ae3cb69c8d4bbc67c8bc2167a27;p=thirdparty%2Fkernel%2Fstable.git

drm/amdgpu/vkms: fix a possible null pointer dereference

[ Upstream commit cd90511557fdfb394bb4ac4c3b539b007383914c ]

In amdgpu_vkms_conn_get_modes(), the return value of drm_cvt_mode()
is assigned to mode, which will lead to a NULL pointer dereference
on failure of drm_cvt_mode(). Add a check to avoid null pointer
dereference.

Signed-off-by: Ma Ke <make_ruc2021@163.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c
index 4e8274de8fc0c..083f9c637a82e 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vkms.c
@@ -238,6 +238,8 @@ static int amdgpu_vkms_conn_get_modes(struct drm_connector *connector)
 
 	for (i = 0; i < ARRAY_SIZE(common_modes); i++) {
 		mode = drm_cvt_mode(dev, common_modes[i].w, common_modes[i].h, 60, false, false, false);
+		if (!mode)
+			continue;
 		drm_mode_probed_add(connector, mode);
 	}