Fix panic on malformed LCM packets#1230
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mohammadmseet-hue wants to merge 1 commit intogoogle:masterfrom
Open
Fix panic on malformed LCM packets#1230mohammadmseet-hue wants to merge 1 commit intogoogle:masterfrom
mohammadmseet-hue wants to merge 1 commit intogoogle:masterfrom
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Add bounds checking for fragmented LCM header fields and fingerprint read. Malformed packets with truncated fragmented headers or missing fingerprint data caused slice bounds panics.
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Summary
Add bounds checking in
LCM.DecodeFromBytesfor fragmented header fields and fingerprint read.Root cause: Fragmented LCM packets read 12 additional bytes (PayloadSize, FragmentOffset, FragmentNumber, TotalFragments) after the initial 8-byte check, but the minimum check only validates 8 bytes. After the channel name loop, the fingerprint read accesses
data[offset:offset+8]without bounds checking.Fix: Check
len(data) >= 20for fragmented headers. Checkoffset+8 <= len(data)before fingerprint read.All existing tests pass.