Harden the zip cache read path against a corrupt X-Size - #493
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A tampered X-Size in a zip cache entry wrapped into an oversized malloc (an allocation-size-too-big abort under ASan). The alloc casts to int (malloct((int) r.size + 1)), so besides a negative size, any positive value at or above INT_MAX truncates negative and wraps too; reject the whole out-of-range span before the load. -#test=cache-corrupt byte-injects a real two-entry zip (bad/oversized/ negative X-Size, blanked X-In-Cache, smashed local header, garbled deflate) and checks each entry degrades to STATUSCODE_INVALID in the same read session as its intact sibling, so one corrupt entry never taints the cache. Only the live zip format is covered; the legacy .dat reader is dead and slated for removal. Re-lands the change orphaned when it was merged into its stacked base branch instead of master. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Signed-off-by: Xavier Roche <roche@httrack.com>
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* X-Size hardening rejected legit headers-only >2GB cache entries The guard from #493 bounds X-Size to [0, INT_MAX) before the header/data split, but a headers-only entry (X-In-Cache: 0) legitimately exceeds INT_MAX: every >2GB non-html file is stored that way, so updates invalidated the entry and re-fetched the file. Keep the negative check global, gate the INT_MAX half on data-in-cache (the write path asserts those fit an int), and reject oversized entries at the one remaining int-sized in-memory read. -#test=cache-corrupt gains a headers-only fixture: a forged >INT_MAX X-Size must survive a header probe with the size intact (fails on the old code) while an in-memory read of the same entry still degrades. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Signed-off-by: Xavier Roche <roche@httrack.com> * review: pin the INT_MAX boundary and the headers-only negative X-Size Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Signed-off-by: Xavier Roche <roche@httrack.com> --------- Signed-off-by: Xavier Roche <roche@httrack.com> Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
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A tampered X-Size in a zip cache entry wrapped into an oversized malloc (an allocation-size-too-big abort under ASan). The alloc casts to int, so besides a negative size, any positive value at or above INT_MAX truncates negative and wraps too; reject the whole out-of-range span before the load.
-#test=cache-corruptbyte-injects a real cache (bad/oversized/negative X-Size, blanked X-In-Cache, smashed header, garbled deflate) and checks each entry is rejected in-session without tainting its sibling.Only the live zip cache format is covered; the legacy .dat format is dead and slated for removal. This re-lands the change that was orphaned when #492 merged into its stacked base branch instead of master.