StarMirror/sandboxed-api
1
0
Fork 0
mirror of https://github.com/google/sandboxed-api.git synced 2024-03-22 13:11:30 +08:00
Code Issues Projects Releases Wiki Activity

Minielf: Use a template to load integers

Browse Source 
Different versions of the `elf.h` header define their own integer types. For
example, even on LP64 systems, a 64-bit ELF integer types may decay into
`unsigned long long` instead of `unsigned long`.

This change replaces the various overloads with a single function template
that is well-defined for all integral types.

PiperOrigin-RevId: 410746713
Change-Id: I4b560f7541802372f01ae3d6f4a56554e51d70c8
This commit is contained in:
Christian Blichmann 2021-11-18 02:15:53 -08:00 committed by Copybara-Service
parent dcfd85d74e
commit c2b7cffe78
1 changed files with 22 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
sandboxed_api/sandbox2/util/minielf.cc
View File

@ -18,6 +18,7 @@
#include <cstddef>
#include <memory>
#include <type_traits>
#include "absl/base/internal/endian.h"
#include "absl/status/status.h"
@ -133,18 +134,25 @@ class ElfParser {
void Load(unsigned char (*dst)[N], const void* src) {
memcpy(dst, src, N);
}
void Load(uint8_t* dst, const void* src) {
*dst = *reinterpret_cast<const char*>(src);
template <typename IntT>
std::enable_if_t<std::is_integral_v<IntT>, void> Load(IntT* dst,
const void* src) {
switch (sizeof(IntT)) {
case 1:
*dst = *reinterpret_cast<const char*>(src);
break;
case 2:
*dst = Load16(src);
break;
case 4:
*dst = Load32(src);
break;
case 8:
*dst = Load64(src);
break;
}
}
void Load(uint16_t* dst, const void* src) { *dst = Load16(src); }
void Load(uint32_t* dst, const void* src) { *dst = Load32(src); }
void Load(uint64_t* dst, const void* src) { *dst = Load64(src); }
void Load(int8_t* dst, const void* src) {
*dst = *reinterpret_cast<const char*>(src);
}
void Load(int16_t* dst, const void* src) { *dst = Load16(src); }
void Load(int32_t* dst, const void* src) { *dst = Load32(src); }
void Load(int64_t* dst, const void* src) { *dst = Load64(src); }
// Reads ELF file size.
absl::Status ReadFileSize();
@ -457,7 +465,9 @@ absl::Status ElfParser::ReadImportedLibrariesFromDynamic(
}
auto offset = strtab_section.sh_offset + dyn.d_un.d_val;
SAPI_RETURN_IF_ERROR(CheckedFSeek(elf_, offset, SEEK_SET));
std::string path(std::min(kMaxLibPathSize, strtab_end - offset), '\0');
std::string path(
std::min(kMaxLibPathSize, static_cast<size_t>(strtab_end - offset)),
'\0');
size_t size = std::fread(&path[0], 1, path.size(), elf_);
path.resize(size);
result_.imported_libraries_.push_back(path.substr(0, path.find('\0')));