From 36d22d82aa202bb199967e9512281e9a53db42c9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 21:33:14 +0200 Subject: Adding upstream version 115.7.0esr. Signed-off-by: Daniel Baumann --- memory/replace/phc/PHC.h | 102 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 102 insertions(+) create mode 100644 memory/replace/phc/PHC.h (limited to 'memory/replace/phc/PHC.h') diff --git a/memory/replace/phc/PHC.h b/memory/replace/phc/PHC.h new file mode 100644 index 0000000000..139a0e81c9 --- /dev/null +++ b/memory/replace/phc/PHC.h @@ -0,0 +1,102 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef PHC_h +#define PHC_h + +#include "mozilla/Assertions.h" +#include "mozilla/Maybe.h" +#include +#include + +namespace mozilla { +namespace phc { + +// Note: a stack trace may have no frames due to a collection problem. +// +// Also note: a more compact stack trace representation could be achieved with +// some effort. +struct StackTrace { + public: + static const size_t kMaxFrames = 16; + + // The number of PCs in the stack trace. + size_t mLength; + + // The PCs in the stack trace. Only the first mLength are initialized. + const void* mPcs[kMaxFrames]; + + public: + StackTrace() : mLength(0) {} +}; + +// Info from PHC about an address in memory. +class AddrInfo { + public: + enum class Kind { + // The address is not in PHC-managed memory. + Unknown = 0, + + // The address is within a PHC page that has never been allocated. A crash + // involving such an address is unlikely in practice, because it would + // require the crash to happen quite early. + NeverAllocatedPage = 1, + + // The address is within a PHC page that is in use. + InUsePage = 2, + + // The address is within a PHC page that has been allocated and then freed. + // A crash involving such an address most likely indicates a + // use-after-free. (A sufficiently wild write -- e.g. a large buffer + // overflow -- could also trigger it, but this is less likely.) + FreedPage = 3, + + // The address is within a PHC guard page. A crash involving such an + // address most likely indicates a buffer overflow. (Again, a sufficiently + // wild write could unluckily trigger it, but this is less likely.) + GuardPage = 4, + }; + + // The page kind. + Kind mKind; + + // The starting address of the allocation. + // - Unknown | NeverAllocatedPage: nullptr. + // - InUsePage | FreedPage: the address of the allocation within the page. + // - GuardPage: the mBaseAddr value from the preceding allocation page. + const void* mBaseAddr; + + // The usable size, which could be bigger than the requested size. + // - Unknown | NeverAllocatePage: 0. + // - InUsePage | FreedPage: the usable size of the allocation within the page. + // - GuardPage: the mUsableSize value from the preceding allocation page. + size_t mUsableSize; + + // The allocation stack. + // - Unknown | NeverAllocatedPage: Nothing. + // - InUsePage | FreedPage: Some. + // - GuardPage: the mAllocStack value from the preceding allocation page. + mozilla::Maybe mAllocStack; + + // The free stack. + // - Unknown | NeverAllocatedPage | InUsePage: Nothing. + // - FreedPage: Some. + // - GuardPage: the mFreeStack value from the preceding allocation page. + mozilla::Maybe mFreeStack; + + // Default to no PHC info. + AddrInfo() + : mKind(Kind::Unknown), + mBaseAddr(nullptr), + mUsableSize(0), + mAllocStack(), + mFreeStack() {} +}; + +} // namespace phc +} // namespace mozilla + +#endif /* PHC_h */ -- cgit v1.2.3