linux-kernel - [PATCH 4.19 2/2] moxart: fix potential use-after-free on remove path

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]

Date:   Wed,  9 Feb 2022 20:14:04 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Ulf Hansson <ulf.hansson@...aro.org>,
        Xiyu Yang <xiyuyang19@...an.edu.cn>,
        Xin Xiong <xiongx18@...an.edu.cn>,
        Xin Tan <tanxin.ctf@...il.com>,
        Tony Lindgren <tony@...mide.com>,
        Yang Li <yang.lee@...ux.alibaba.com>,
        linux-mmc@...r.kernel.org, whitehat002 <hackyzh002@...il.com>
Subject: [PATCH 4.19 2/2] moxart: fix potential use-after-free on remove path

From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

commit bd2db32e7c3e35bd4d9b8bbff689434a50893546 upstream.

It was reported that the mmc host structure could be accessed after it
was freed in moxart_remove(), so fix this by saving the base register of
the device and using it instead of the pointer dereference.

Cc: Ulf Hansson <ulf.hansson@...aro.org>
Cc: Xiyu Yang <xiyuyang19@...an.edu.cn>
Cc: Xin Xiong <xiongx18@...an.edu.cn>
Cc: Xin Tan <tanxin.ctf@...il.com>
Cc: Tony Lindgren <tony@...mide.com>
Cc: Yang Li <yang.lee@...ux.alibaba.com>
Cc: linux-mmc@...r.kernel.org
Cc: stable <stable@...r.kernel.org>
Reported-by: whitehat002 <hackyzh002@...il.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Link: https://lore.kernel.org/r/20220127071638.4057899-1-gregkh@linuxfoundation.org
Signed-off-by: Ulf Hansson <ulf.hansson@...aro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/mmc/host/moxart-mmc.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/mmc/host/moxart-mmc.c
+++ b/drivers/mmc/host/moxart-mmc.c
@@ -696,12 +696,12 @@ static int moxart_remove(struct platform
 		if (!IS_ERR(host->dma_chan_rx))
 			dma_release_channel(host->dma_chan_rx);
 		mmc_remove_host(mmc);
-		mmc_free_host(mmc);
 
 		writel(0, host->base + REG_INTERRUPT_MASK);
 		writel(0, host->base + REG_POWER_CONTROL);
 		writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF,
 		       host->base + REG_CLOCK_CONTROL);
+		mmc_free_host(mmc);
 	}
 	return 0;
 }