Fix cdn back source range size overflow

[jim3ma]

Signed-off-by: Jim Ma majinjing3@gmail.com

Description

Related Issue

Motivation and Context

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation Update (if none of the other choices apply)

Checklist:

• Code compiles correctly.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[codecov-commenter]

Codecov Report

Merging #550 (00c5c5f) into main (5286be0) will increase coverage by 0.05%.
The diff coverage is 69.23%.

@@            Coverage Diff             @@
##             main     #550      +/-   ##
==========================================
+ Coverage   39.47%   39.53%   +0.05%     
==========================================
  Files          86       86              
  Lines        6559     6562       +3     
==========================================
+ Hits         2589     2594       +5     
+ Misses       3599     3597       -2     
  Partials      371      371              

Flag	Coverage Δ
e2etests	∅ <ø> (∅)
unittests	39.53% <69.23%> (+0.05%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
cdnsystem/daemon/cdn/cache_writer.go	79.20% <69.23%> (+0.63%)	⬆️
client/daemon/peer/peertask_file.go	54.05% <0.00%> (-0.39%)	⬇️
client/daemon/peer/peertask_base.go	34.75% <0.00%> (+0.63%)	⬆️