linux-kernel - [PATCHv2] Check whether divisor is non-zero before division

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-next>] [day] [month] [year] [list]

Date: Thu, 23 May 2024 17:26:08 +0800
From: Shichao Lai <shichaorai@...il.com>
To: stern@...land.harvard.edu,
	gregkh@...uxfoundation.org,
	oneukum@...e.com
Cc: linux-usb@...r.kernel.org,
	usb-storage@...ts.one-eyed-alien.net,
	linux-kernel@...r.kernel.org,
	Shichao Lai <shichaorai@...il.com>,
	xingwei lee <xrivendell7@...il.com>,
	yue sun <samsun1006219@...il.com>
Subject: [PATCHv2] Check whether divisor is non-zero before division

Since uzonesize may be zero, so judgements for non-zero are nessesary in both place.
Previous check is moved out of loop, and one more check is added in alauda_write_lba.

Reported-by: xingwei lee <xrivendell7@...il.com>
Reported-by: yue sun <samsun1006219@...il.com>
Signed-off-by: Shichao Lai <shichaorai@...il.com>
---
 drivers/usb/storage/alauda.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/usb/storage/alauda.c b/drivers/usb/storage/alauda.c
index 115f05a6201a..a6e60ef5cb0d 100644
--- a/drivers/usb/storage/alauda.c
+++ b/drivers/usb/storage/alauda.c
@@ -818,6 +818,8 @@ static int alauda_write_lba(struct us_data *us, u16 lba,
 	unsigned int blocksize = MEDIA_INFO(us).blocksize;
 	unsigned int lba_offset = lba % uzonesize;
 	unsigned int new_pba_offset;
+	if (!uzonesize)
+		return USB_STOR_TRANSPORT_ERROR;
 	unsigned int zone = lba / uzonesize;
 
 	alauda_ensure_map_for_zone(us, zone);
@@ -923,6 +925,8 @@ static int alauda_read_data(struct us_data *us, unsigned long address,
 	unsigned int uzonesize = MEDIA_INFO(us).uzonesize;
 	struct scatterlist *sg;
 	int result;
+	if (!uzonesize)
+		return USB_STOR_TRANSPORT_ERROR;
 
 	/*
 	 * Since we only read in one block at a time, we have to create
-- 
2.34.1