[PATCH 5.10 213/390] fpga: prevent integer overflow in dfl_feature_ioctl_set_irq()

From: Greg Kroah-Hartman
Date: Mon Oct 24 2022 - 09:16:30 EST


From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ Upstream commit 939bc5453b8cbdde9f1e5110ce8309aedb1b501a ]

The "hdr.count * sizeof(s32)" multiplication can overflow on 32 bit
systems leading to memory corruption. Use array_size() to fix that.

Fixes: 322b598be4d9 ("fpga: dfl: introduce interrupt trigger setting API")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Acked-by: Xu Yilun <yilun.xu@xxxxxxxxx>
Link: https://lore.kernel.org/r/YxBAtYCM38dM7yzI@kili
Signed-off-by: Xu Yilun <yilun.xu@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/fpga/dfl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
index b450870b75ed..eb8a6e329af9 100644
--- a/drivers/fpga/dfl.c
+++ b/drivers/fpga/dfl.c
@@ -1857,7 +1857,7 @@ long dfl_feature_ioctl_set_irq(struct platform_device *pdev,
return -EINVAL;

fds = memdup_user((void __user *)(arg + sizeof(hdr)),
- hdr.count * sizeof(s32));
+ array_size(hdr.count, sizeof(s32)));
if (IS_ERR(fds))
return PTR_ERR(fds);

--
2.35.1