From: Wang Jun <1742789905@qq.com>
Date: Tue, 10 Mar 2026 01:14:20 +0000 (+0800)
Subject: fbdev: viafb: check ioremap return value in viafb_lcd_get_mobile_state
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f044788088ef55e9855b17b7984ffe522c40c093;p=thirdparty%2Flinux.git

fbdev: viafb: check ioremap return value in viafb_lcd_get_mobile_state

The function viafb_lcd_get_mobile_state() calls ioremap() without
checking the return value. If ioremap() fails (returns NULL), the
subsequent readw() will cause a NULL pointer dereference.

Signed-off-by: Wang Jun <1742789905@qq.com>
Signed-off-by: Helge Deller <deller@gmx.de>
---

diff --git a/drivers/video/fbdev/via/lcd.c b/drivers/video/fbdev/via/lcd.c
index 8673fced87492..3fa2304fbda7e 100644
--- a/drivers/video/fbdev/via/lcd.c
+++ b/drivers/video/fbdev/via/lcd.c
@@ -954,6 +954,9 @@ bool viafb_lcd_get_mobile_state(bool *mobile)
 	u16 start_pattern;
 
 	biosptr = ioremap(romaddr, 0x10000);
+	if (!biosptr)
+		return false;
+
 	start_pattern = readw(biosptr);
 
 	/* Compare pattern */