[PATCH] scsi: mpt3sas: Fix a possible divide-by-zero bug in base_mod64()
From: Tuo Li
Date: Wed Aug 11 2021 - 09:25:05 EST
The variable divisor is checked in:
if (!divisor)
This indicates that divisor can be NULL.
If so, a divide-by-zero bug will occur:
remainder = do_div(dividend, divisor);
To fix the possible bug, the function returns 0 when divisor is zero.
Reported-by: TOTE Robot <oslab@xxxxxxxxxxxxxxx>
Signed-off-by: Tuo Li <islituo@xxxxxxxxx>
---
drivers/scsi/mpt3sas/mpt3sas_base.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c
index 19b1c0cf5f2a..3550998ea38b 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_base.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
@@ -1594,8 +1594,10 @@ static u32 base_mod64(u64 dividend, u32 divisor)
{
u32 remainder;
- if (!divisor)
+ if (!divisor) {
pr_err("mpt3sas: DIVISOR is zero, in div fn\n");
+ return 0;
+ }
remainder = do_div(dividend, divisor);
return remainder;
}
--
2.25.1