llvm-project

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//===-- sanitizer_procmaps_fuchsia.cpp
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//----------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// Information about the process mappings (Fuchsia-specific parts).
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//===----------------------------------------------------------------------===//
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#include "sanitizer_platform.h"
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#if SANITIZER_FUCHSIA
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#include <zircon/process.h>
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#include <zircon/syscalls.h>
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#include "sanitizer_common.h"
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#include "sanitizer_procmaps.h"
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namespace __sanitizer {
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// The cache flag is ignored on Fuchsia because a process can always get this
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// information via its process-self handle.
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MemoryMappingLayout::MemoryMappingLayout(bool) { Reset(); }
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void MemoryMappingLayout::Reset() {
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  data_.data.clear();
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  data_.current = 0;
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  size_t count;
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  zx_status_t status = _zx_object_get_info(
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      _zx_process_self(), ZX_INFO_PROCESS_MAPS, nullptr, 0, nullptr, &count);
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  if (status != ZX_OK) {
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    return;
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  }
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  size_t filled;
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  do {
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    data_.data.resize(count);
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    status = _zx_object_get_info(
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        _zx_process_self(), ZX_INFO_PROCESS_MAPS, data_.data.data(),
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        count * sizeof(zx_info_maps_t), &filled, &count);
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    if (status != ZX_OK) {
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      data_.data.clear();
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      return;
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    }
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  } while (filled < count);
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}
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MemoryMappingLayout::~MemoryMappingLayout() {}
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bool MemoryMappingLayout::Error() const { return data_.data.empty(); }
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bool MemoryMappingLayout::Next(MemoryMappedSegment *segment) {
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  while (data_.current < data_.data.size()) {
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    const auto &entry = data_.data[data_.current++];
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    if (entry.type == ZX_INFO_MAPS_TYPE_MAPPING) {
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      segment->start = entry.base;
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      segment->end = entry.base + entry.size;
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      segment->offset = entry.u.mapping.vmo_offset;
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      const auto flags = entry.u.mapping.mmu_flags;
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      segment->protection =
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          ((flags & ZX_VM_PERM_READ) ? kProtectionRead : 0) |
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          ((flags & ZX_VM_PERM_WRITE) ? kProtectionWrite : 0) |
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          ((flags & ZX_VM_PERM_EXECUTE) ? kProtectionExecute : 0);
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      if (segment->filename && segment->filename_size > 0) {
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        uptr len = Min(sizeof(entry.name), segment->filename_size) - 1;
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        internal_strncpy(segment->filename, entry.name, len);
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        segment->filename[len] = 0;
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      }
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      return true;
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    }
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  }
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  return false;
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}
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}  // namespace __sanitizer
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#endif  // SANITIZER_FUCHSIA
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