tree 6c836ad06b2468d86c9d87e50fcc452239cabe57
parent b21fe4d3c6b5fb890bd888b0d27ecc9cfae2904b
author Matt Morehouse <mascasa@google.com> 1636469552 -0800
committer Copybara-Service <copybara-worker@google.com> 1636470354 -0800

[HWASan] Ensure RNG is initialized in GenerateRandomTag

Fixes a CHECK-failure caused by glibc's pthread_getattr_np
implementation calling realloc.  Essentially, Thread::GenerateRandomTag
gets called during Thread::Init and before Thread::InitRandomState:

  HWAddressSanitizer: CHECK failed: hwasan_thread.cpp:134 "((random_buffer_)) != (0)" (0x0, 0x0) (tid=314)
    #0 0x55845475a662 in __hwasan::CheckUnwind()
    #1 0x558454778797 in __sanitizer::CheckFailed(char const*, int, char const*, unsigned long long, unsigned long long)
    #2 0x558454766461 in __hwasan::Thread::GenerateRandomTag(unsigned long)
    #3 0x55845475c58b in __hwasan::HwasanAllocate(__sanitizer::StackTrace*, unsigned long, unsigned long, bool)
    #4 0x55845475c80a in __hwasan::hwasan_realloc(void*, unsigned long, __sanitizer::StackTrace*)
    #5 0x5584547608aa in realloc
    #6 0x7f6f3a3d8c2c in pthread_getattr_np
    #7 0x5584547790dc in __sanitizer::GetThreadStackTopAndBottom(bool, unsigned long*, unsigned long*)
    #8 0x558454779651 in __sanitizer::GetThreadStackAndTls(bool, unsigned long*, unsigned long*, unsigned long*, unsigned long*)
    #9 0x558454761bca in __hwasan::Thread::InitStackAndTls(__hwasan::Thread::InitState const*)
    #10 0x558454761e5c in __hwasan::HwasanThreadList::CreateCurrentThread(__hwasan::Thread::InitState const*)
    #11 0x55845476184f in __hwasan_thread_enter
    #12 0x558454760def in HwasanThreadStartFunc(void*)
    #13 0x7f6f3a3d6fa2 in start_thread
    #14 0x7f6f3a15b4ce in __clone

Also reverts 7a3fb71c3cbdd80666335fa8f6f071b43f0b922a, as it's now
unneeded.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D113045

GitOrigin-RevId: 846ec2c3ccbc8e6fb5cbbaa207b93941af16f434