Re: [syzbot] BUG: unable to handle kernel NULL pointer dereference in fbcon_putcs

syzbot
2024-09-16T00:46:46Z

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Subject: BUG: unable to handle kernel NULL pointer dereference in fbcon_putcs
Author: qianqiang.liu@163.com

#syz test

diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 3f7333dca508..96c1262cc981 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -1284,7 +1284,7 @@ static void fbcon_putcs(struct vc_data *vc, const u16 *s, unsigned int count,
struct fbcon_display *p = &fb_display[vc->vc_num];
struct fbcon_ops *ops = info->fbcon_par;

- if (!fbcon_is_inactive(vc, info))
+ if (!fbcon_is_inactive(vc, info) && ops->putcs)
ops->putcs(vc, info, s, count, real_y(p, ypos), xpos,
get_color(vc, info, scr_readw(s), 1),
get_color(vc, info, scr_readw(s), 0));

--
Best,
Qianqiang Liu