linux-kernel - [PATCH 5.13 001/127] mtd: cfi_cmdset_0002: fix crash when erasing/writing AMD cards

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: <20210824165607.709387-2-sashal@kernel.org>
Date:   Tue, 24 Aug 2021 12:54:01 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Andreas Persson <andreasp56@...look.com>,
        Miquel Raynal <miquel.raynal@...tlin.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: [PATCH 5.13 001/127] mtd: cfi_cmdset_0002: fix crash when erasing/writing AMD cards

From: Andreas Persson <andreasp56@...look.com>

commit 2394e628738933aa014093d93093030f6232946d upstream.

Erasing an AMD linear flash card (AM29F016D) crashes after the first
sector has been erased. Likewise, writing to it crashes after two bytes
have been written. The reason is a missing check for a null pointer -
the cmdset_priv field is not set for this type of card.

Fixes: 4844ef80305d ("mtd: cfi_cmdset_0002: Add support for polling status register")
Signed-off-by: Andreas Persson <andreasp56@...look.com>
Signed-off-by: Miquel Raynal <miquel.raynal@...tlin.com>
Link: https://lore.kernel.org/linux-mtd/DB6P189MB05830B3530B8087476C5CFE4C1159@DB6P189MB0583.EURP189.PROD.OUTLOOK.COM
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 drivers/mtd/chips/cfi_cmdset_0002.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index 3097e93787f7..a761134fd3be 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -119,7 +119,7 @@ static int cfi_use_status_reg(struct cfi_private *cfi)
 	struct cfi_pri_amdstd *extp = cfi->cmdset_priv;
 	u8 poll_mask = CFI_POLL_STATUS_REG | CFI_POLL_DQ;
 
-	return extp->MinorVersion >= '5' &&
+	return extp && extp->MinorVersion >= '5' &&
 		(extp->SoftwareFeatures & poll_mask) == CFI_POLL_STATUS_REG;
 }
 
-- 
2.30.2