[PATCH 3/4] misc: xilinx_sdfec: Prevent a divide by zero in xsdfec_reg0_write()

From: Dan Carpenter
Date: Wed Aug 21 2019 - 03:10:15 EST


The "psize" value comes from the user so we need to verify that it's
non-zero before we check if "n % psize" or it will crash.

Fixes: 20ec628e8007 ("misc: xilinx_sdfec: Add ability to configure LDPC")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
The parentheses in this condition are a no-op. They're just confusing.
Perhaps something else was intended?

drivers/misc/xilinx_sdfec.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/misc/xilinx_sdfec.c b/drivers/misc/xilinx_sdfec.c
index 813b82c59360..3fc53d20abf3 100644
--- a/drivers/misc/xilinx_sdfec.c
+++ b/drivers/misc/xilinx_sdfec.c
@@ -460,7 +460,7 @@ static int xsdfec_reg0_write(struct xsdfec_dev *xsdfec, u32 n, u32 k, u32 psize,
{
u32 wdata;

- if (n < XSDFEC_REG0_N_MIN || n > XSDFEC_REG0_N_MAX ||
+ if (n < XSDFEC_REG0_N_MIN || n > XSDFEC_REG0_N_MAX || psize == 0 ||
(n > XSDFEC_REG0_N_MUL_P * psize) || n <= k || ((n % psize) != 0)) {
dev_dbg(xsdfec->dev, "N value is not in range");
return -EINVAL;
--
2.20.1