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

From: Shichao Lai
Date: Thu May 23 2024 - 05:26:52 EST


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@xxxxxxxxx>
Reported-by: yue sun <samsun1006219@xxxxxxxxx>
Signed-off-by: Shichao Lai <shichaorai@xxxxxxxxx>
---
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