Bugfix - Fix alloc limit#393
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farhanfarasdak wants to merge 1 commit into
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Background
a 5-byte array32 header declares up to ~4.29B elements, and decodeSliceValue pre-allocates that many before reading any data, because the cap check flags & disableAllocLimitFlag != 1 can never be true (the flag value is 8, so flags & 8 is 0 or 8, never 1). Plus the uncapped interface{} path. It can cause DoS via memory exhaustion; why a competent dev writes "read count → make(T,count)"; and the four traps when fixing it (spotting the typo, missing the interface/map paths, breaking semantics by hard-truncating, and preserving the DisableAllocLimit opt-out).