Fix out of bounds memory read in add_compile_string
#165
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This PR fixes out of bounds memory read in
add_compile_string
revealed by fuzzing fluent-bit:https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=46086
The root cause is that a call to
enclen
incompile_string_node
results in a call toonigenc_mbclen_approximate
.When the value of
p
passed to the function is\xf2
even though it is the last byte in multibyte sequince (the next byte is unexpected string terminator \0) theonigenc_mbclen_approximate
returns it's size as 4. The size is added to the overall string length and results in reading past the end of the string.