#include <lsan-virtual-address-space.h>

Inheritance diagram for v8::base::LsanVirtualAddressSpace:

Collaboration diagram for v8::base::LsanVirtualAddressSpace:

Public Member Functions
	LsanVirtualAddressSpace (std::unique_ptr< v8::VirtualAddressSpace > vas)

	~LsanVirtualAddressSpace () override=default

void	SetRandomSeed (int64_t seed) override

Address	RandomPageAddress () override

Address	AllocatePages (Address hint, size_t size, size_t alignment, PagePermissions permissions) override

void	FreePages (Address address, size_t size) override

Address	AllocateSharedPages (Address hint, size_t size, PagePermissions permissions, PlatformSharedMemoryHandle handle, uint64_t offset) override

void	FreeSharedPages (Address address, size_t size) override

bool	SetPagePermissions (Address address, size_t size, PagePermissions permissions) override

bool	RecommitPages (Address address, size_t size, PagePermissions permissions) override

bool	AllocateGuardRegion (Address address, size_t size) override

void	FreeGuardRegion (Address address, size_t size) override

bool	CanAllocateSubspaces () override

std::unique_ptr< VirtualAddressSpace >	AllocateSubspace (Address hint, size_t size, size_t alignment, PagePermissions max_page_permissions) override

bool	DiscardSystemPages (Address address, size_t size) override

bool	DecommitPages (Address address, size_t size) override

Public Member Functions inherited from v8::VirtualAddressSpace
	VirtualAddressSpace (size_t page_size, size_t allocation_granularity, Address base, size_t size, PagePermissions max_page_permissions)

virtual	~VirtualAddressSpace ()=default

size_t	page_size () const

size_t	allocation_granularity () const

Address	base () const

size_t	size () const

PagePermissions	max_page_permissions () const

bool	Contains (Address address) const

Private Attributes
std::unique_ptr< v8::VirtualAddressSpace >	vas_

Additional Inherited Members
Public Types inherited from v8::VirtualAddressSpace
using	Address = uintptr_t

Static Public Attributes inherited from v8::VirtualAddressSpace
static constexpr Address	kNoHint = 0

Detailed Description

Definition at line 20 of file lsan-virtual-address-space.h.

Constructor & Destructor Documentation

◆ LsanVirtualAddressSpace()

v8::base::LsanVirtualAddressSpace::LsanVirtualAddressSpace ( std::unique_ptr< v8::VirtualAddressSpace > vas )

explicit

Definition at line 17 of file lsan-virtual-address-space.cc.

◆ ~LsanVirtualAddressSpace()

v8::base::LsanVirtualAddressSpace::~LsanVirtualAddressSpace ( )

overridedefault

Member Function Documentation

◆ AllocateGuardRegion()

bool v8::base::LsanVirtualAddressSpace::AllocateGuardRegion	(	Address	address,
		size_t	size )

inlineoverridevirtual

Creates a guard region at the specified address.

Guard regions are guaranteed to cause a fault when accessed and generally do not count towards any memory consumption limits. Further, allocating guard regions can usually not fail in subspaces if the region does not overlap with another region, subspace, or page allocation.

Parameters

address	The start address of the guard region. Must be aligned to the allocation_granularity().
size	The size of the guard region in bytes. Must be a multiple of the allocation_granularity().

Returns: true on success, false otherwise.

Implements v8::VirtualAddressSpace.

Definition at line 55 of file lsan-virtual-address-space.h.

◆ AllocatePages()

Address v8::base::LsanVirtualAddressSpace::AllocatePages	(	Address	hint,
		size_t	size,
		size_t	alignment,
		PagePermissions	permissions )

overridevirtual

Implements v8::VirtualAddressSpace.

Definition at line 26 of file lsan-virtual-address-space.cc.

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◆ AllocateSharedPages()

Address v8::base::LsanVirtualAddressSpace::AllocateSharedPages	(	Address	hint,
		size_t	size,
		PagePermissions	permissions,
		PlatformSharedMemoryHandle	handle,
		uint64_t	offset )

overridevirtual

Allocates shared memory pages with the given permissions.

Parameters

hint	Placement hint. See AllocatePages.
size	The size of the allocation in bytes. Must be a multiple of the allocation_granularity().
permissions	The page permissions of the newly allocated pages.
handle	A platform-specific handle to a shared memory object. See the SharedMemoryHandleFromX routines above for ways to obtain these.
offset	The offset in the shared memory object at which the mapping should start. Must be a multiple of the allocation_granularity().

Returns: the start address of the allocated pages on success, zero on failure.

Implements v8::VirtualAddressSpace.

Definition at line 45 of file lsan-virtual-address-space.cc.

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◆ AllocateSubspace()

std::unique_ptr< VirtualAddressSpace > v8::base::LsanVirtualAddressSpace::AllocateSubspace	(	Address	hint,
		size_t	size,
		size_t	alignment,
		PagePermissions	max_page_permissions )

overridevirtual

Implements v8::VirtualAddressSpace.

Definition at line 65 of file lsan-virtual-address-space.cc.

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◆ CanAllocateSubspaces()

bool v8::base::LsanVirtualAddressSpace::CanAllocateSubspaces ( )

inlineoverridevirtual

Whether this instance can allocate subspaces or not.

Returns: true if subspaces can be allocated, false if not.

Implements v8::VirtualAddressSpace.

Definition at line 63 of file lsan-virtual-address-space.h.

◆ DecommitPages()

bool v8::base::LsanVirtualAddressSpace::DecommitPages	(	Address	address,
		size_t	size )

inlineoverridevirtual

Decommits any wired memory pages in the given range, allowing the OS to reclaim them, and marks the region as inacessible (kNoAccess). The address range stays reserved and can be accessed again later by changing its permissions. However, in that case the memory content is guaranteed to be zero-initialized again. The memory must have been previously allocated by a call to AllocatePages.

Returns: true on success, false otherwise.

Implements v8::VirtualAddressSpace.

Definition at line 73 of file lsan-virtual-address-space.h.

◆ DiscardSystemPages()

bool v8::base::LsanVirtualAddressSpace::DiscardSystemPages	(	Address	address,
		size_t	size )

inlineoverridevirtual

Frees memory in the given [address, address + size) range. address and size should be aligned to the page_size(). The next write to this memory area brings the memory transparently back. This should be treated as a hint to the OS that the pages are no longer needed. It does not guarantee that the pages will be discarded immediately or at all.

Returns: true on success, false otherwise. Since this method is only a hint, a successful invocation does not imply that pages have been removed.

Reimplemented from v8::VirtualAddressSpace.

Definition at line 69 of file lsan-virtual-address-space.h.

◆ FreeGuardRegion()

void v8::base::LsanVirtualAddressSpace::FreeGuardRegion	(	Address	address,
		size_t	size )

inlineoverridevirtual

Frees an existing guard region.

This function will terminate the process on failure as this implies a bug in the client. As such, there is no return value.

Parameters

address	The start address of the guard region to free. This address must have previously been used as address parameter in a successful invocation of AllocateGuardRegion.
size	The size in bytes of the guard region to free. This must match the size passed to AllocateGuardRegion when the region was created.

Implements v8::VirtualAddressSpace.

Definition at line 59 of file lsan-virtual-address-space.h.

◆ FreePages()

void v8::base::LsanVirtualAddressSpace::FreePages	(	Address	address,
		size_t	size )

overridevirtual

Frees previously allocated pages.

This function will terminate the process on failure as this implies a bug in the client. As such, there is no return value.

Parameters

address	The start address of the pages to free. This address must have been obtained through a call to AllocatePages.
size	The size in bytes of the region to free. This must match the size passed to AllocatePages when the pages were allocated.

Implements v8::VirtualAddressSpace.

Definition at line 38 of file lsan-virtual-address-space.cc.

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◆ FreeSharedPages()

void v8::base::LsanVirtualAddressSpace::FreeSharedPages	(	Address	address,
		size_t	size )

overridevirtual

Frees previously allocated shared pages.

This function will terminate the process on failure as this implies a bug in the client. As such, there is no return value.

Parameters

address	The start address of the pages to free. This address must have been obtained through a call to AllocateSharedPages.
size	The size in bytes of the region to free. This must match the size passed to AllocateSharedPages when the pages were allocated.

Implements v8::VirtualAddressSpace.

Definition at line 58 of file lsan-virtual-address-space.cc.

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◆ RandomPageAddress()

Address v8::base::LsanVirtualAddressSpace::RandomPageAddress ( )

inlineoverridevirtual

Returns a random address inside this address space, suitable for page allocations hints.

Returns: a random address aligned to allocation_granularity().

Implements v8::VirtualAddressSpace.

Definition at line 31 of file lsan-virtual-address-space.h.

◆ RecommitPages()

bool v8::base::LsanVirtualAddressSpace::RecommitPages	(	Address	address,
		size_t	size,
		PagePermissions	permissions )

inlineoverridevirtual

Recommits discarded pages in the given range with given permissions. Discarded pages must be recommitted with their original permissions before they are used again.

Parameters

address	The start address of the range. Must be aligned to page_size().
size	The size in bytes of the range. Must be a multiple of page_size().
permissions	The permissions for the range that the pages must have.

Returns: true on success, false otherwise.

Implements v8::VirtualAddressSpace.

Definition at line 50 of file lsan-virtual-address-space.h.

◆ SetPagePermissions()

bool v8::base::LsanVirtualAddressSpace::SetPagePermissions	(	Address	address,
		size_t	size,
		PagePermissions	permissions )

inlineoverridevirtual

Sets permissions of all allocated pages in the given range.

This operation can fail due to OOM, in which case false is returned. If the operation fails for a reason other than OOM, this function will terminate the process as this implies a bug in the client.

Parameters

address	The start address of the range. Must be aligned to page_size().
size	The size in bytes of the range. Must be a multiple of page_size().
permissions	The new permissions for the range.

Returns: true on success, false on OOM.

Implements v8::VirtualAddressSpace.

Definition at line 45 of file lsan-virtual-address-space.h.

◆ SetRandomSeed()

void v8::base::LsanVirtualAddressSpace::SetRandomSeed ( int64_t seed )

inlineoverridevirtual

Sets the random seed so that GetRandomPageAddress() will generate repeatable sequences of random addresses.

Parameters

The	seed for the PRNG.

Implements v8::VirtualAddressSpace.

Definition at line 27 of file lsan-virtual-address-space.h.

Member Data Documentation

◆ vas_

std::unique_ptr<v8::VirtualAddressSpace> v8::base::LsanVirtualAddressSpace::vas_

private

Definition at line 78 of file lsan-virtual-address-space.h.

The documentation for this class was generated from the following files:

src/base/sanitizer/lsan-virtual-address-space.h
src/base/sanitizer/lsan-virtual-address-space.cc

Public Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ LsanVirtualAddressSpace()

◆ ~LsanVirtualAddressSpace()

Member Function Documentation

◆ AllocateGuardRegion()

◆ AllocatePages()

◆ AllocateSharedPages()

◆ AllocateSubspace()

◆ CanAllocateSubspaces()

◆ DecommitPages()

◆ DiscardSystemPages()

◆ FreeGuardRegion()

◆ FreePages()

◆ FreeSharedPages()

◆ RandomPageAddress()

◆ RecommitPages()

◆ SetPagePermissions()

◆ SetRandomSeed()

Member Data Documentation

◆ vas_