1 //===-- guarded_pool_allocator_fuchsia.cpp ----------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "gwp_asan/guarded_pool_allocator.h" 10 #include "gwp_asan/utilities.h" 11 12 #include <assert.h> 13 #include <stdint.h> 14 #include <string.h> 15 #include <zircon/process.h> 16 #include <zircon/syscalls.h> 17 18 namespace gwp_asan { 19 void GuardedPoolAllocator::initPRNG() { 20 _zx_cprng_draw(&getThreadLocals()->RandomState, sizeof(uint32_t)); 21 } 22 23 void *GuardedPoolAllocator::map(size_t Size, const char *Name) const { 24 assert((Size % State.PageSize) == 0); 25 zx_handle_t Vmo; 26 zx_status_t Status = _zx_vmo_create(Size, 0, &Vmo); 27 Check(Status == ZX_OK, "Failed to create Vmo"); 28 _zx_object_set_property(Vmo, ZX_PROP_NAME, Name, strlen(Name)); 29 zx_vaddr_t Addr; 30 Status = _zx_vmar_map(_zx_vmar_root_self(), 31 ZX_VM_PERM_READ | ZX_VM_PERM_WRITE | ZX_VM_ALLOW_FAULTS, 32 0, Vmo, 0, Size, &Addr); 33 Check(Status == ZX_OK, "Vmo mapping failed"); 34 _zx_handle_close(Vmo); 35 return reinterpret_cast<void *>(Addr); 36 } 37 38 void GuardedPoolAllocator::unmap(void *Ptr, size_t Size) const { 39 assert((reinterpret_cast<uintptr_t>(Ptr) % State.PageSize) == 0); 40 assert((Size % State.PageSize) == 0); 41 zx_status_t Status = _zx_vmar_unmap(_zx_vmar_root_self(), 42 reinterpret_cast<zx_vaddr_t>(Ptr), Size); 43 Check(Status == ZX_OK, "Vmo unmapping failed"); 44 } 45 46 void *GuardedPoolAllocator::reserveGuardedPool(size_t Size) { 47 assert((Size % State.PageSize) == 0); 48 zx_vaddr_t Addr; 49 const zx_status_t Status = _zx_vmar_allocate( 50 _zx_vmar_root_self(), 51 ZX_VM_CAN_MAP_READ | ZX_VM_CAN_MAP_WRITE | ZX_VM_CAN_MAP_SPECIFIC, 0, 52 Size, &GuardedPagePoolPlatformData.Vmar, &Addr); 53 Check(Status == ZX_OK, "Failed to reserve guarded pool allocator memory"); 54 _zx_object_set_property(GuardedPagePoolPlatformData.Vmar, ZX_PROP_NAME, 55 kGwpAsanGuardPageName, strlen(kGwpAsanGuardPageName)); 56 return reinterpret_cast<void *>(Addr); 57 } 58 59 void GuardedPoolAllocator::unreserveGuardedPool() { 60 const zx_handle_t Vmar = GuardedPagePoolPlatformData.Vmar; 61 assert(Vmar != ZX_HANDLE_INVALID && Vmar != _zx_vmar_root_self()); 62 Check(_zx_vmar_destroy(Vmar) == ZX_OK, "Failed to destroy a vmar"); 63 Check(_zx_handle_close(Vmar) == ZX_OK, "Failed to close a vmar"); 64 GuardedPagePoolPlatformData.Vmar = ZX_HANDLE_INVALID; 65 } 66 67 void GuardedPoolAllocator::allocateInGuardedPool(void *Ptr, size_t Size) const { 68 assert((reinterpret_cast<uintptr_t>(Ptr) % State.PageSize) == 0); 69 assert((Size % State.PageSize) == 0); 70 zx_handle_t Vmo; 71 zx_status_t Status = _zx_vmo_create(Size, 0, &Vmo); 72 Check(Status == ZX_OK, "Failed to create vmo"); 73 _zx_object_set_property(Vmo, ZX_PROP_NAME, kGwpAsanAliveSlotName, 74 strlen(kGwpAsanAliveSlotName)); 75 const zx_handle_t Vmar = GuardedPagePoolPlatformData.Vmar; 76 assert(Vmar != ZX_HANDLE_INVALID && Vmar != _zx_vmar_root_self()); 77 const size_t Offset = 78 reinterpret_cast<uintptr_t>(Ptr) - State.GuardedPagePool; 79 zx_vaddr_t P; 80 Status = _zx_vmar_map(Vmar, 81 ZX_VM_PERM_READ | ZX_VM_PERM_WRITE | 82 ZX_VM_ALLOW_FAULTS | ZX_VM_SPECIFIC, 83 Offset, Vmo, 0, Size, &P); 84 Check(Status == ZX_OK, "Vmo mapping failed"); 85 _zx_handle_close(Vmo); 86 } 87 88 void GuardedPoolAllocator::deallocateInGuardedPool(void *Ptr, 89 size_t Size) const { 90 assert((reinterpret_cast<uintptr_t>(Ptr) % State.PageSize) == 0); 91 assert((Size % State.PageSize) == 0); 92 const zx_handle_t Vmar = GuardedPagePoolPlatformData.Vmar; 93 assert(Vmar != ZX_HANDLE_INVALID && Vmar != _zx_vmar_root_self()); 94 const zx_status_t Status = 95 _zx_vmar_unmap(Vmar, reinterpret_cast<zx_vaddr_t>(Ptr), Size); 96 Check(Status == ZX_OK, "Vmar unmapping failed"); 97 } 98 99 size_t GuardedPoolAllocator::getPlatformPageSize() { 100 return _zx_system_get_page_size(); 101 } 102 103 void GuardedPoolAllocator::installAtFork() {} 104 } // namespace gwp_asan 105