[PATCH] D110365: [llvm][profile] Do not read padding when printing build IDs

[Roland McGrath via Phabricator via llvm-commits]

mcgrathr added inline comments.


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Comment at: llvm/lib/ProfileData/InstrProfReader.cpp:548
+
     // Increment by binary id length data type size.
     BI += sizeof(BinaryIdLen);
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The following code is still not robust to invalid BinaryIdLen values.
It needs to compare against Remaining (accounting for the size field just read) before using the value in arithmetic to avoid overflow risks.  Computing a pointer from untrusted input and then comparing it to another pointer is never robust.



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Comment at: llvm/lib/ProfileData/InstrProfReader.cpp:558
     // Increment by binary id data length.
     BI += BinaryIdLen;
     if (BI > (const uint8_t *)DataBuffer->getBufferEnd())
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What is the packing protocol?  It seems wise to pad after *each* ID to make the next size field naturally-aligned, rather than having the second size field be misaligned if the first build ID length is not a multiple of 8.



Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D110365/new/

https://reviews.llvm.org/D110365