From 817332784c16d8659469dd2de49151f51067eb00 Mon Sep 17 00:00:00 2001
From: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Date: Tue, 14 Dec 2021 09:41:26 +0800
Subject: drm/ast: potential dereference of null pointer
Git-commit: fea3fdf975dd9f3e5248afaab8fe023db313f005
Patch-mainline: v5.16-rc6
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
The return value of kzalloc() needs to be checked.
To avoid use of null pointer '&ast_state->base' in case of the
failure of alloc.
Fixes: f0adbc382b8b ("drm/ast: Allocate initial CRTC state of the correct size")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20211214014126.2211535-1-jiasheng@iscas.ac.cn
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/ast/ast_mode.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index 1e30eaeb0e1b..d5c98f79d58d 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -1121,7 +1121,10 @@ static void ast_crtc_reset(struct drm_crtc *crtc)
if (crtc->state)
crtc->funcs->atomic_destroy_state(crtc, crtc->state);
- __drm_atomic_helper_crtc_reset(crtc, &ast_state->base);
+ if (ast_state)
+ __drm_atomic_helper_crtc_reset(crtc, &ast_state->base);
+ else
+ __drm_atomic_helper_crtc_reset(crtc, NULL);
}
static struct drm_crtc_state *
--
2.38.1