linux-kernel - [PATCH 5.15 738/913] video: fbdev: w100fb: Reset global state

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20220405070401.956283853@linuxfoundation.org>
Date:   Tue,  5 Apr 2022 09:30:00 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Evgeny Novikov <novikov@...ras.ru>,
        Kirill Shilimanov <kirill.shilimanov@...wei.com>,
        Helge Deller <deller@....de>, Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.15 738/913] video: fbdev: w100fb: Reset global state

From: Evgeny Novikov <novikov@...ras.ru>

[ Upstream commit 8738ddcac644964ae128ccd3d80d48773c8d528e ]

w100fb_probe() did not reset the global state to its initial state. This
can result in invocation of iounmap() even when there was not the
appropriate successful call of ioremap(). For instance, this may be the
case if first probe fails after two successful ioremap() while second
probe fails when first ioremap() fails. The similar issue is with
w100fb_remove(). The patch fixes both bugs.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Evgeny Novikov <novikov@...ras.ru>
Co-developed-by: Kirill Shilimanov <kirill.shilimanov@...wei.com>
Signed-off-by: Kirill Shilimanov <kirill.shilimanov@...wei.com>
Signed-off-by: Helge Deller <deller@....de>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/video/fbdev/w100fb.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/video/fbdev/w100fb.c b/drivers/video/fbdev/w100fb.c
index d96ab28f8ce4..4e641a780726 100644
--- a/drivers/video/fbdev/w100fb.c
+++ b/drivers/video/fbdev/w100fb.c
@@ -770,12 +770,18 @@ static int w100fb_probe(struct platform_device *pdev)
 		fb_dealloc_cmap(&info->cmap);
 		kfree(info->pseudo_palette);
 	}
-	if (remapped_fbuf != NULL)
+	if (remapped_fbuf != NULL) {
 		iounmap(remapped_fbuf);
-	if (remapped_regs != NULL)
+		remapped_fbuf = NULL;
+	}
+	if (remapped_regs != NULL) {
 		iounmap(remapped_regs);
-	if (remapped_base != NULL)
+		remapped_regs = NULL;
+	}
+	if (remapped_base != NULL) {
 		iounmap(remapped_base);
+		remapped_base = NULL;
+	}
 	if (info)
 		framebuffer_release(info);
 	return err;
@@ -795,8 +801,11 @@ static int w100fb_remove(struct platform_device *pdev)
 	fb_dealloc_cmap(&info->cmap);
 
 	iounmap(remapped_base);
+	remapped_base = NULL;
 	iounmap(remapped_regs);
+	remapped_regs = NULL;
 	iounmap(remapped_fbuf);
+	remapped_fbuf = NULL;
 
 	framebuffer_release(info);
 
-- 
2.34.1