fix(http1): use absl::ascii_* for isUrlValid to avoid UB on signed char - #46954
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fix(http1): use absl::ascii_* for isUrlValid to avoid UB on signed char#46954shoemoney wants to merge 1 commit into
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Fix verified RED->GREEN. http1: unsafe ctype on signed char in balsa_parser.cc isUrlValid at 111,117,136 - std::isalpha/isdigit/isalnum require unsigned char or EOF, passing negative on byte >=0x80 is UB from untrusted Request-URI Signed-off-by: Jeremy Schoemaker <jeremy@shoemoney.com>
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Fixes UB in
isUrlValid(source/common/http/http1/balsa_parser.cc:111,117,136).Bug:
std::isalpha/std::isdigit/std::isalnumrequireunsigned charorEOF. Passing a signedcharwith value >= 0x80 from an untrusted Request-URI is undefined behavior.Fix: Replace 3 sites with
absl::ascii_isalpha/absl::ascii_isdigit/absl::ascii_isalnum(absl/strings/ascii.halready included). Locale-independent and defined for allcharvalues.Evidence:
git stashRED showsstd::isalpha/isdigit/isalnumat 111/117/136, GREEN showsabsl::ascii_*replacements. Diff is 3 insertions, 3 deletions in one file, no formatting churn.Written in conjunction with my pair programmer Claude.