From 01faae5193d6190b7b3aa93dae43f514e866d652 Mon Sep 17 00:00:00 2001
From: Du Cheng <ducheng2@gmail.com>
Date: Fri, 12 Mar 2021 16:14:21 +0800
Subject: [PATCH] drivers: video: fbcon: fix NULL dereference in fbcon_cursor()
Git-commit: 01faae5193d6190b7b3aa93dae43f514e866d652
Patch-mainline: v5.12-rc6
References: git-fixes
add null-check on function pointer before dereference on ops->cursor
Reported-by: syzbot+b67aaae8d3a927f68d20@syzkaller.appspotmail.com
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Du Cheng <ducheng2@gmail.com>
Link: https://lore.kernel.org/r/20210312081421.452405-1-ducheng2@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/video/fbdev/core/fbcon.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 44a5cd2f54cc..3406067985b1 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -1333,6 +1333,9 @@ static void fbcon_cursor(struct vc_data *vc, int mode)
ops->cursor_flash = (mode == CM_ERASE) ? 0 : 1;
+ if (!ops->cursor)
+ return;
+
ops->cursor(vc, info, mode, get_color(vc, info, c, 1),
get_color(vc, info, c, 0));
}
--
2.26.2