fix(scan): stop reading C pointer casts as ReDoS - #141
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`redos-nested-quantifier` carried no `languages`, so it ran on every file the walker handed it. Its pattern looks for `(`, text, `*`, `)`, `*` — which is exactly how C spells a cast followed by a dereference. `*(char *)*p` is a nested quantifier as far as the rule is concerned. Found by scanning inspektor-gadget: across 1186 files the rule fired once, on a `bpf_probe_read_user` call in an eBPF C program. Not a regex, in a language that has no regex literals. Scoped to the languages where a regex literal can appear rather than narrowing the pattern, because no pattern helps here — there is nothing in a C file for this rule to legitimately find. `other` also covers C++, Rust and Zig, which share the cast-then-deref spelling. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
ThreatCrush Security Scan69 finding(s) HIGH/CRITICAL: 12 | MEDIUM: 56 | LOW: 1
…and 19 more. Full results in the Security tab. Snippets are redacted; ThreatCrush never prints matched credential material. |
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redos-nested-quantifiercarried nolanguages, so it ran on every file thewalker handed it. Its pattern looks for
(, text,*,),*— which isexactly how C spells a cast followed by a dereference.
Found while scanning inspektor-gadget:
across 1186 files the rule fired exactly once, on a
bpf_probe_read_usercallin an eBPF C program. Not a regex, in a language that has no regex literals.
Scoping is the fix rather than a cleverer pattern — there is nothing in a C
file for this rule to legitimately find, no matter how the pattern is written.
otheralso covers C++, Rust and Zig, which share the cast-then-derefspelling.
Verification
pnpm testinpackages/scan— 253 passed (10 files), including the new case.pnpm typecheck— clean.delta is
redos-nested-quantifieratgadgets/trace_malloc/program.bpf.c:238.Nothing else moved.
🤖 Generated with Claude Code