Remove unused code

This commit is contained in:
topjohnwu 2024-03-30 21:03:51 -07:00
parent 2cb0af1ff3
commit 2051836a73
4 changed files with 0 additions and 386 deletions

View File

@ -1,144 +0,0 @@
// This file implements all missing symbols that should exist in normal API 23
// libc.a but missing in our extremely lean libc.a replacements.
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/syscall.h>
#include <sys/xattr.h>
extern "C" {
#if !defined(__LP64__)
// Add "hacky" libc.a missing symbols back
// All symbols in this file are weak, so a vanilla NDK should still link properly
#include "fortify.hpp"
// Original source: https://github.com/freebsd/freebsd/blob/master/contrib/file/src/getline.c
// License: BSD, full copyright notice please check original source
[[gnu::weak]]
ssize_t getdelim(char **buf, size_t *bufsiz, int delimiter, FILE *fp) {
char *ptr, *eptr;
if (*buf == nullptr || *bufsiz == 0) {
*bufsiz = BUFSIZ;
if ((*buf = (char *) malloc(*bufsiz)) == nullptr)
return -1;
}
for (ptr = *buf, eptr = *buf + *bufsiz;;) {
int c = fgetc(fp);
if (c == -1) {
if (feof(fp))
return ptr == *buf ? -1 : ptr - *buf;
else
return -1;
}
*ptr++ = c;
if (c == delimiter) {
*ptr = '\0';
return ptr - *buf;
}
if (ptr + 2 >= eptr) {
char *nbuf;
size_t nbufsiz = *bufsiz * 2;
ssize_t d = ptr - *buf;
if ((nbuf = (char *) realloc(*buf, nbufsiz)) == nullptr)
return -1;
*buf = nbuf;
*bufsiz = nbufsiz;
eptr = nbuf + nbufsiz;
ptr = nbuf + d;
}
}
}
[[gnu::weak]]
ssize_t getline(char **buf, size_t *bufsiz, FILE *fp) {
return getdelim(buf, bufsiz, '\n', fp);
}
// Missing system call wrappers
[[gnu::weak]]
ssize_t readlinkat(int dirfd, const char *pathname, char *buf, size_t bufsiz) {
return syscall(__NR_readlinkat, dirfd, pathname, buf, bufsiz);
}
[[gnu::weak]]
int symlinkat(const char *target, int newdirfd, const char *linkpath) {
return syscall(__NR_symlinkat, target, newdirfd, linkpath);
}
[[gnu::weak]]
int linkat(int olddirfd, const char *oldpath,
int newdirfd, const char *newpath, int flags) {
return syscall(__NR_linkat, olddirfd, oldpath, newdirfd, newpath, flags);
}
[[gnu::weak]]
int faccessat(int dirfd, const char *pathname, int mode, int flags) {
return syscall(__NR_faccessat, dirfd, pathname, mode, flags);
}
[[gnu::weak]]
int mkfifo(const char *path, mode_t mode) {
return mknod(path, (mode & ~S_IFMT) | S_IFIFO, 0);
}
[[gnu::weak]]
int fsetxattr(int fd, const char *name, const void *value, size_t size, int flags) {
return syscall(__NR_fsetxattr, fd, name, value, size, flags);
}
[[gnu::weak]]
int lsetxattr(const char *path, const char *name, const void *value, size_t size, int flags) {
return syscall(__NR_lsetxattr, path, name, value, size, flags);
}
#define SPLIT_64(v) (unsigned)((v) & 0xFFFFFFFF), (unsigned)((v) >> 32)
#if defined(__arm__)
// Why the additional 0 is required: https://man7.org/linux/man-pages/man2/syscall.2.html
[[gnu::weak]]
int ftruncate64(int fd, off64_t length) {
return syscall(__NR_ftruncate64, fd, 0, SPLIT_64(length));
}
#elif defined(__i386__)
[[gnu::weak]]
int ftruncate64(int fd, off64_t length) {
return syscall(__NR_ftruncate64, fd, SPLIT_64(length));
}
#endif
[[gnu::weak]]
void android_set_abort_message(const char *) {}
extern FILE __sF[];
[[gnu::weak]] FILE* stdin = &__sF[0];
[[gnu::weak]] FILE* stdout = &__sF[1];
[[gnu::weak]] FILE* stderr = &__sF[2];
#endif // !defined(__LP64__)
[[maybe_unused]]
int __wrap_renameat(int old_dir_fd, const char *old_path, int new_dir_fd, const char *new_path) {
long out = syscall(__NR_renameat, old_dir_fd, old_path, new_dir_fd, new_path);
if (out == -1 && errno == ENOSYS) {
out = syscall(__NR_renameat2, old_dir_fd, old_path, new_dir_fd, new_path, 0);
}
return static_cast<int>(out);
}
[[maybe_unused]]
int __wrap_rename(const char *old_path, const char *new_path) {
return __wrap_renameat(AT_FDCWD, old_path, AT_FDCWD, new_path);
}
} // extern "C"

View File

@ -1,144 +0,0 @@
// Original source: https://android.googlesource.com/platform/bionic/+/master/libc/bionic/fortify.cpp
// License: AOSP, full copyright notice please check original source
#include <sys/stat.h>
#include <fcntl.h>
#undef _FORTIFY_SOURCE
extern void __vloge(const char* fmt, va_list ap);
static inline __noreturn __printflike(1, 2) void __fortify_fatal(const char* fmt, ...) {
va_list args;
va_start(args, fmt);
__vloge(fmt, args);
va_end(args);
abort();
}
static inline void __check_count(const char* fn, const char* identifier, size_t value) {
if (__predict_false(value > SSIZE_MAX)) {
__fortify_fatal("%s: %s %zu > SSIZE_MAX", fn, identifier, value);
}
}
static inline void __check_buffer_access(const char* fn, const char* action,
size_t claim, size_t actual) {
if (__predict_false(claim > actual)) {
__fortify_fatal("%s: prevented %zu-byte %s %zu-byte buffer", fn, claim, action, actual);
}
}
[[gnu::weak]]
void* __memcpy_chk(void* dst, const void* src, size_t count, size_t dst_len) {
__check_count("memcpy", "count", count);
__check_buffer_access("memcpy", "write into", count, dst_len);
return __call_bypassing_fortify(memcpy)(dst, src, count);
}
[[gnu::weak]]
char* __strcpy_chk(char* dst, const char* src, size_t dst_len) {
// TODO: optimize so we don't scan src twice.
size_t src_len = __builtin_strlen(src) + 1;
__check_buffer_access("strcpy", "write into", src_len, dst_len);
return __builtin_strcpy(dst, src);
}
[[gnu::weak]]
size_t __strlcpy_chk(char* dst, const char* src,
size_t supplied_size, size_t dst_len_from_compiler) {
__check_buffer_access("strlcpy", "write into", supplied_size, dst_len_from_compiler);
return __call_bypassing_fortify(strlcpy)(dst, src, supplied_size);
}
[[gnu::weak]]
char* __strchr_chk(const char* p, int ch, size_t s_len) {
for (;; ++p, s_len--) {
if (__predict_false(s_len == 0)) {
__fortify_fatal("strchr: prevented read past end of buffer");
}
if (*p == static_cast<char>(ch)) {
return const_cast<char*>(p);
}
if (*p == '\0') {
return nullptr;
}
}
}
[[gnu::weak]]
char* __strcat_chk(char* dst, const char* src, size_t dst_buf_size) {
char* save = dst;
size_t dst_len = __strlen_chk(dst, dst_buf_size);
dst += dst_len;
dst_buf_size -= dst_len;
while ((*dst++ = *src++) != '\0') {
dst_buf_size--;
if (__predict_false(dst_buf_size == 0)) {
__fortify_fatal("strcat: prevented write past end of %zu-byte buffer", dst_buf_size);
}
}
return save;
}
[[gnu::weak]]
size_t __strlen_chk(const char* s, size_t s_len) {
// TODO: "prevented" here would be a lie because this strlen can run off the end.
// strlen is too important to be expensive, so we wanted to be able to call the optimized
// implementation, but I think we need to implement optimized assembler __strlen_chk routines.
size_t ret = __builtin_strlen(s);
if (__predict_false(ret >= s_len)) {
__fortify_fatal("strlen: detected read past end of buffer");
}
return ret;
}
[[gnu::weak]]
int __vsprintf_chk(char* dst, int /*flags*/,
size_t dst_len_from_compiler, const char* format, va_list va) {
// The compiler uses SIZE_MAX to mean "no idea", but our vsnprintf rejects sizes that large.
int result = __call_bypassing_fortify(vsnprintf)(dst,
dst_len_from_compiler == SIZE_MAX ? SSIZE_MAX : dst_len_from_compiler,
format, va);
// Try to catch failures after the fact...
__check_buffer_access("vsprintf", "write into", result + 1, dst_len_from_compiler);
return result;
}
[[gnu::weak]]
mode_t __umask_chk(mode_t mode) {
if (__predict_false((mode & 0777) != mode)) {
__fortify_fatal("umask: called with invalid mask %o", mode);
}
return __umask_real(mode);
}
[[gnu::weak]]
ssize_t __read_chk(int fd, void* buf, size_t count, size_t buf_size) {
__check_count("read", "count", count);
__check_buffer_access("read", "write into", count, buf_size);
return __call_bypassing_fortify(read)(fd, buf, count);
}
static inline bool needs_mode(int flags) {
return ((flags & O_CREAT) == O_CREAT) || ((flags & O_TMPFILE) == O_TMPFILE);
}
static inline int force_O_LARGEFILE(int flags) {
return flags | O_LARGEFILE;
}
[[gnu::weak]]
int __open_2(const char* pathname, int flags) {
if (needs_mode(flags)) __fortify_fatal("open: called with O_CREAT/O_TMPFILE but no mode");
return __openat_real(AT_FDCWD, pathname, force_O_LARGEFILE(flags), 0);
}
[[gnu::weak]]
int __openat_2(int fd, const char* pathname, int flags) {
if (needs_mode(flags)) __fortify_fatal("open: called with O_CREAT/O_TMPFILE but no mode");
return __openat_real(fd, pathname, force_O_LARGEFILE(flags), 0);
}
[[gnu::weak]]
int __vsnprintf_chk(char* dst, size_t supplied_size, int /*flags*/,
size_t dst_len_from_compiler, const char* format, va_list va) {
__check_buffer_access("vsnprintf", "write into", supplied_size, dst_len_from_compiler);
return __call_bypassing_fortify(vsnprintf)(dst, supplied_size, format, va);
}

View File

@ -101,86 +101,6 @@ void parse_prop_file(const char *file, const function<bool(string_view, string_v
parse_prop_file(fp.get(), fn);
}
std::vector<mount_info> parse_mount_info(const char *pid) {
char buf[PATH_MAX] = {};
ssprintf(buf, sizeof(buf), "/proc/%s/mountinfo", pid);
std::vector<mount_info> result;
file_readline(buf, [&result](string_view line) -> bool {
int root_start = 0, root_end = 0;
int target_start = 0, target_end = 0;
int vfs_option_start = 0, vfs_option_end = 0;
int type_start = 0, type_end = 0;
int source_start = 0, source_end = 0;
int fs_option_start = 0, fs_option_end = 0;
int optional_start = 0, optional_end = 0;
unsigned int id, parent, maj, min;
sscanf(line.data(),
"%u " // (1) id
"%u " // (2) parent
"%u:%u " // (3) maj:min
"%n%*s%n " // (4) mountroot
"%n%*s%n " // (5) target
"%n%*s%n" // (6) vfs options (fs-independent)
"%n%*[^-]%n - " // (7) optional fields
"%n%*s%n " // (8) FS type
"%n%*s%n " // (9) source
"%n%*s%n", // (10) fs options (fs specific)
&id, &parent, &maj, &min, &root_start, &root_end, &target_start,
&target_end, &vfs_option_start, &vfs_option_end,
&optional_start, &optional_end, &type_start, &type_end,
&source_start, &source_end, &fs_option_start, &fs_option_end);
auto root = line.substr(root_start, root_end - root_start);
auto target = line.substr(target_start, target_end - target_start);
auto vfs_option =
line.substr(vfs_option_start, vfs_option_end - vfs_option_start);
++optional_start;
--optional_end;
auto optional = line.substr(
optional_start,
optional_end - optional_start > 0 ? optional_end - optional_start : 0);
auto type = line.substr(type_start, type_end - type_start);
auto source = line.substr(source_start, source_end - source_start);
auto fs_option =
line.substr(fs_option_start, fs_option_end - fs_option_start);
unsigned int shared = 0;
unsigned int master = 0;
unsigned int propagate_from = 0;
if (auto pos = optional.find("shared:"); pos != std::string_view::npos) {
shared = parse_int(optional.substr(pos + 7));
}
if (auto pos = optional.find("master:"); pos != std::string_view::npos) {
master = parse_int(optional.substr(pos + 7));
}
if (auto pos = optional.find("propagate_from:");
pos != std::string_view::npos) {
propagate_from = parse_int(optional.substr(pos + 15));
}
result.emplace_back(mount_info {
.id = id,
.parent = parent,
.device = static_cast<dev_t>(makedev(maj, min)),
.root {root},
.target {target},
.vfs_option {vfs_option},
.optional {
.shared = shared,
.master = master,
.propagate_from = propagate_from,
},
.type {type},
.source {source},
.fs_option {fs_option},
});
return true;
});
return result;
}
sDIR make_dir(DIR *dp) {
return sDIR(dp, [](DIR *dp){ return dp ? closedir(dp) : 1; });
}

View File

@ -20,23 +20,6 @@ static inline T align_padding(T v, int a) {
return align_to(v, a) - v;
}
struct mount_info {
unsigned int id;
unsigned int parent;
dev_t device;
std::string root;
std::string target;
std::string vfs_option;
struct {
unsigned int shared;
unsigned int master;
unsigned int propagate_from;
} optional;
std::string type;
std::string source;
std::string fs_option;
};
struct mmap_data : public byte_data {
static_assert((sizeof(void *) == 8 && BLKGETSIZE64 == 0x80081272) ||
(sizeof(void *) == 4 && BLKGETSIZE64 == 0x80041272));
@ -77,7 +60,6 @@ void file_readline(const char *file, const std::function<bool(std::string_view)>
void parse_prop_file(FILE *fp, const std::function<bool(std::string_view, std::string_view)> &fn);
void parse_prop_file(const char *file,
const std::function<bool(std::string_view, std::string_view)> &fn);
std::vector<mount_info> parse_mount_info(const char *pid);
std::string resolve_preinit_dir(const char *base_dir);
using sFILE = std::unique_ptr<FILE, decltype(&fclose)>;