SQLi: store a variable value without the leading '@', matching C - #3
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C's parse_var assigns the token value from after the '@' symbols, so the value is the name alone and the '@' count is kept separately. The port stored the '@' in the value, so the function fold that matches a variable named like PASSWORD/USER/... compared against "@password" and never fired, typing `@pasSword(` as a variable where C types it as a function. The fingerprints then diverged (`v(f(1` vs the blacklisted `f(f(1`). Assign the value from after the '@' and reconstruct the '@' prefix from `count` where the source form is printed (the token-file and folding test formatters), as C's print_var does. Found by the 2-hour fuzz campaign, about 2.8M executions in. A dedicated differential test pins it; full corpus stays at 0.
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The 2-hour differential fuzz campaign (added in the previous PR) found
this about 2.8M executions in, well beyond the per-pull-request smoke
test's reach. It is a false negative and the first divergence outside the
strchr-NUL family.The divergence
@pasSword(pasSword(2isf(f(1in C (a blacklisted pattern, so SQLi)but was
v(f(1in the port (benign). The function fold converts abareword or variable named
PASSWORD/USER/... followed by(into afunction. C's
parse_varstores the variable value from after the@(the name alone; the
@count is a separate field), so the fold comparespasSwordand fires. The port stored the@in the value, so it compared@pasSword, which never matched, and the variable kept its type.Fix
Assign the variable value from after the
@symbols, matching C. Theprinted source form is reconstructed from the
@count where it is needed(the token-file and folding test formatters), exactly as C's
print_vardoes. A dedicated differential test pins
@pasSword(.Gate
Full-corpus differential (162,963 inputs) stays at 0 on verdicts and
fingerprints. The nightly campaign continues from here.