linux-kernel - [PATCH] ubi: Refuse attaching if mtd's erasesize is 0

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 for Android: free password hash cracker in your pocket

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

Message-ID: <20230423111041.684297-1-chengzhihao1@huawei.com>
Date:   Sun, 23 Apr 2023 19:10:41 +0800
From:   Zhihao Cheng <chengzhihao1@...wei.com>
To:     <richard@....at>, <miquel.raynal@...tlin.com>, <vigneshr@...com>,
        <haver@...t.ibm.com>, <s.hauer@...gutronix.de>, <yhao016@....edu>
CC:     <linux-mtd@...ts.infradead.org>, <linux-kernel@...r.kernel.org>
Subject: [PATCH] ubi: Refuse attaching if mtd's erasesize is 0

There exists mtd devices with zero erasesize, which will trigger a
divide-by-zero exception while attaching ubi device.
Fix it by refusing attaching if mtd's erasesize is 0.

Fixes: 801c135ce73d ("UBI: Unsorted Block Images")
Reported-by: Yu Hao <yhao016@....edu>
Link: https://lore.kernel.org/lkml/977347543.226888.1682011999468.JavaMail.zimbra@nod.at/T/
Signed-off-by: Zhihao Cheng <chengzhihao1@...wei.com>
---
 drivers/mtd/ubi/build.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 6a2d1ef8d43c..69e92c31ace0 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -896,6 +896,13 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
 		return -EINVAL;
 	}
 
+	/* UBI cannot work on flashes with zero erasesize. */
+	if (!mtd->erasesize) {
+		pr_err("ubi: refuse attaching mtd%d - zero erasesize flash is not supported\n",
+			mtd->index);
+		return -EINVAL;
+	}
+
 	if (ubi_num == UBI_DEV_NUM_AUTO) {
 		/* Search for an empty slot in the @ubi_devices array */
 		for (ubi_num = 0; ubi_num < UBI_MAX_DEVICES; ubi_num++)
-- 
2.31.1