Prevent DoS (OOM) via massive packets #95
Merged
+7
−10
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When maxHttpBufferSize is large (1e8 bytes), a payload of length 100MB can be sent like so:
99999991:422222222222222222222222222222222222222222222...
This massive packet can cause OOM (out of memory) via building up many many
ConsOneByteString
objects due to concatenation: 99999989ConsOneByteString
s and then converting the massive string to aNumber
.The performance can be improved to avoid this by using
substring
rather than building the string via concatenation.Below I tried one payload of length 7e7 as the 1e8 payload took so long to process that it timed out before it could run out of memory.
With this fix, the processing is faster and it doesn't use anywhere near as much memory.