Patch "fpga: prevent integer overflow in dfl_feature_ioctl_set_irq()" has been added to the 5.10-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    fpga: prevent integer overflow in dfl_feature_ioctl_set_irq()

to the 5.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     fpga-prevent-integer-overflow-in-dfl_feature_ioctl_s.patch
and it can be found in the queue-5.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 94d5522ebb6b553ca019f5c1b76a2cace1b3523a
Author: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Date:   Thu Sep 1 08:18:45 2022 +0300

    fpga: prevent integer overflow in dfl_feature_ioctl_set_irq()
    
    [ 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>

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);