fix: guard Delete against out-of-range endOffset+tokEnd on fuzz input#282
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SAY-5 wants to merge 1 commit intobuger:masterfrom
Open
fix: guard Delete against out-of-range endOffset+tokEnd on fuzz input#282SAY-5 wants to merge 1 commit intobuger:masterfrom
SAY-5 wants to merge 1 commit intobuger:masterfrom
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Delete's nested-key branch assumed that endOffset+tokEnd (the byte after the found value's closing token) always stayed inside the input buffer. Fuzz-generated or truncated input can leave the computed index one-past the buffer, and the subsequent data[endOffset+tokEnd] read panicked with 'index out of range', killing the whole process before any caller could recover - this is how Delete surfaced as a deadly signal under libFuzzer (buger#274). Bail out early and return the original buffer unchanged when the next-byte index is out of range. That is equivalent to 'there is nothing after the match to remove', which is the correct no-op semantic here: the caller gets their input back, no panic, no partial delete. Closes buger#274 Signed-off-by: SAY-5 <SAY-5@users.noreply.github.com>
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What
Fixes #274.
Delete's nested-key branch assumed thatendOffset+tokEnd(the byte after the found value's closing token) always stayed inside the input buffer. Fuzz-generated or truncated input can leave the computed index one-past the buffer, and the subsequentdata[endOffset+tokEnd]read panics with:killing the whole process before any caller could recover - this is how Delete surfaces as a deadly signal under libFuzzer / oss-fuzz.
Fix
Bail out early and return the original buffer unchanged when the next-byte index is out of range. That matches the correct no-op semantic: 'there is nothing after the match to remove', so the caller gets their input back, no panic, no partial delete. The happy path is unchanged.
Verification
Locally on macOS, go 1.26.2:
gofmt -s -l parser.go: cleango vet ./...: clean (the existingbytes_unsafe_test.go:26 reflect.StringHeadernote is pre-existing and untouched by this PR)go test -race -count=1 ./...: passCloses #274