Properly detect 2SI init

Fix #2994
This commit is contained in:
topjohnwu 2020-09-02 21:20:00 -07:00
parent b73d5753f2
commit f32a29911b
3 changed files with 26 additions and 15 deletions

View File

@ -178,3 +178,10 @@ void load_kernel_info(cmdline *cmd) {
LOGD("hardware=[%s]\n", cmd->hardware);
LOGD("hardware.platform=[%s]\n", cmd->hardware_plat);
}
bool check_two_stage() {
if (access("/apex", F_OK) == 0)
return true;
auto init = raw_data::mmap_ro("/init");
return init.find("selinux_setup");
}

View File

@ -40,6 +40,14 @@ int data_holder::patch(str_pairs list) {
return count;
}
bool data_holder::find(string_view pattern) {
for (uint8_t *p = buf, *eof = buf + sz; p < eof; ++p) {
if (memcmp(p, pattern.data(), pattern.length() + 1) == 0)
return true;
}
return false;
}
void data_holder::consume(data_holder &other) {
buf = other.buf;
sz = other.sz;
@ -47,16 +55,6 @@ void data_holder::consume(data_holder &other) {
other.sz = 0;
}
template <>
auto_data<MMAP>::~auto_data<MMAP>() {
if (buf) munmap(buf, sz);
}
template <>
auto_data<HEAP>::~auto_data<HEAP>() {
free(buf);
}
auto_data<HEAP> raw_data::read(int fd) {
auto_data<HEAP> data;
fd_full_read(fd, data.buf, data.sz);
@ -75,9 +73,11 @@ auto_data<MMAP> raw_data::mmap_rw(const char *name) {
return data;
}
// Explicit instantiation
template struct auto_data<HEAP>;
template struct auto_data<MMAP>;
auto_data<MMAP> raw_data::mmap_ro(const char *name) {
auto_data<MMAP> data;
::mmap_ro(name, data.buf, data.sz);
return data;
}
static bool unxz(int fd, const uint8_t *buf, size_t size) {
uint8_t out[8192];
@ -229,7 +229,7 @@ int main(int argc, char *argv[]) {
// This will also mount /sys and /proc
load_kernel_info(&cmd);
bool two_stage = access("/apex", F_OK) == 0;
bool two_stage = check_two_stage();
if (cmd.skip_initramfs) {
if (two_stage)
init = new SARFirstStageInit(argv, &cmd);

View File

@ -21,12 +21,12 @@ struct data_holder {
size_t sz = 0;
using str_pairs = std::initializer_list<std::pair<std::string_view, std::string_view>>;
int patch(str_pairs list);
bool find(std::string_view pattern);
protected:
void consume(data_holder &other);
};
enum data_type { HEAP, MMAP };
template <data_type T>
struct auto_data : public data_holder {
auto_data<T>() = default;
@ -35,11 +35,14 @@ struct auto_data : public data_holder {
~auto_data<T>() {}
auto_data<T>& operator=(auto_data<T> &&other) { consume(other); return *this; }
};
template <> inline auto_data<MMAP>::~auto_data<MMAP>() { if (buf) munmap(buf, sz); }
template <> inline auto_data<HEAP>::~auto_data<HEAP>() { free(buf); }
namespace raw_data {
auto_data<HEAP> read(const char *name);
auto_data<HEAP> read(int fd);
auto_data<MMAP> mmap_rw(const char *name);
auto_data<MMAP> mmap_ro(const char *name);
}
struct fstab_entry {
@ -59,6 +62,7 @@ struct fstab_entry {
#define DEFAULT_DT_DIR "/proc/device-tree/firmware/android"
void load_kernel_info(cmdline *cmd);
bool check_two_stage();
int dump_magisk(const char *path, mode_t mode);
int magisk_proxy_main(int argc, char *argv[]);
void setup_klog();