On Mon, Mar 18, 2019 at 05:45:20PM +0200, Nikolay Borisov wrote:
> qgroup_rsv_size is calculated as the product of
> outstanding_extent * fs_info->nodesize. The product is calculated with
> 32 bith precision since both variables are defined as u32. Yet
> qgroup_rsv_size expects a 64 bit result.
>
> Avoid possible multiplication overflow by casting outstanding_extent to
> u64.
>
> Fixes-coverity-id: 1435101
> ff6bc37eb7f6 ("btrfs: qgroup: Use independent and accurate per inode qgroup
> rsv")
Fixes: hash ("subject")
I've added a note about the worst case when the overflow would happen,
which is 65536 outstanding extents with 64K nodesize. Unlikely to
happen.
