Merge "init: more unique_fd, less goto" am: 401c9cb330 am: 0908ca721a am: 613fd13dc2
am: bb0c02c06e
Change-Id: I72fe94758c651684fd9edcf7d657bd2c3096596b
diff --git a/init/init.cpp b/init/init.cpp
index 5693b0f..4cd2e2b 100644
--- a/init/init.cpp
+++ b/init/init.cpp
@@ -73,6 +73,7 @@
using android::base::boot_clock;
using android::base::GetProperty;
using android::base::Timer;
+using android::base::unique_fd;
namespace android {
namespace init {
@@ -291,65 +292,49 @@
* time. We do not reboot or halt on failures, as this is a best-effort
* attempt.
*/
-static int mix_hwrng_into_linux_rng_action(const std::vector<std::string>& args)
-{
- int result = -1;
- int hwrandom_fd = -1;
- int urandom_fd = -1;
- char buf[512];
- ssize_t chunk_size;
- size_t total_bytes_written = 0;
-
- hwrandom_fd = TEMP_FAILURE_RETRY(
- open("/dev/hw_random", O_RDONLY | O_NOFOLLOW | O_CLOEXEC));
+static int mix_hwrng_into_linux_rng_action(const std::vector<std::string>& args) {
+ unique_fd hwrandom_fd(
+ TEMP_FAILURE_RETRY(open("/dev/hw_random", O_RDONLY | O_NOFOLLOW | O_CLOEXEC)));
if (hwrandom_fd == -1) {
if (errno == ENOENT) {
- LOG(ERROR) << "/dev/hw_random not found";
+ LOG(INFO) << "/dev/hw_random not found";
// It's not an error to not have a Hardware RNG.
- result = 0;
- } else {
- PLOG(ERROR) << "Failed to open /dev/hw_random";
+ return 0;
}
- goto ret;
+ PLOG(ERROR) << "Failed to open /dev/hw_random";
+ return -1;
}
- urandom_fd = TEMP_FAILURE_RETRY(
- open("/dev/urandom", O_WRONLY | O_NOFOLLOW | O_CLOEXEC));
+ unique_fd urandom_fd(
+ TEMP_FAILURE_RETRY(open("/dev/urandom", O_WRONLY | O_NOFOLLOW | O_CLOEXEC)));
if (urandom_fd == -1) {
PLOG(ERROR) << "Failed to open /dev/urandom";
- goto ret;
+ return -1;
}
+ char buf[512];
+ size_t total_bytes_written = 0;
while (total_bytes_written < sizeof(buf)) {
- chunk_size = TEMP_FAILURE_RETRY(
- read(hwrandom_fd, buf, sizeof(buf) - total_bytes_written));
+ ssize_t chunk_size =
+ TEMP_FAILURE_RETRY(read(hwrandom_fd, buf, sizeof(buf) - total_bytes_written));
if (chunk_size == -1) {
PLOG(ERROR) << "Failed to read from /dev/hw_random";
- goto ret;
+ return -1;
} else if (chunk_size == 0) {
LOG(ERROR) << "Failed to read from /dev/hw_random: EOF";
- goto ret;
+ return -1;
}
chunk_size = TEMP_FAILURE_RETRY(write(urandom_fd, buf, chunk_size));
if (chunk_size == -1) {
PLOG(ERROR) << "Failed to write to /dev/urandom";
- goto ret;
+ return -1;
}
total_bytes_written += chunk_size;
}
LOG(INFO) << "Mixed " << total_bytes_written << " bytes from /dev/hw_random into /dev/urandom";
- result = 0;
-
-ret:
- if (hwrandom_fd != -1) {
- close(hwrandom_fd);
- }
- if (urandom_fd != -1) {
- close(urandom_fd);
- }
- return result;
+ return 0;
}
static void security_failure() {
@@ -425,45 +410,40 @@
* ec9ee4acd97c drivers: char: random: add get_random_long()
* 5ef11c35ce86 mm: ASLR: use get_random_long()
*/
-static int set_mmap_rnd_bits_action(const std::vector<std::string>& args)
-{
- int ret = -1;
-
- /* values are arch-dependent */
+static int set_mmap_rnd_bits_action(const std::vector<std::string>& args) {
+/* values are arch-dependent */
#if defined(USER_MODE_LINUX)
/* uml does not support mmap_rnd_bits */
- ret = 0;
+ return 0;
#elif defined(__aarch64__)
/* arm64 supports 18 - 33 bits depending on pagesize and VA_SIZE */
if (set_mmap_rnd_bits_min(33, 24, false)
&& set_mmap_rnd_bits_min(16, 16, true)) {
- ret = 0;
+ return 0;
}
#elif defined(__x86_64__)
/* x86_64 supports 28 - 32 bits */
if (set_mmap_rnd_bits_min(32, 32, false)
&& set_mmap_rnd_bits_min(16, 16, true)) {
- ret = 0;
+ return 0;
}
#elif defined(__arm__) || defined(__i386__)
/* check to see if we're running on 64-bit kernel */
bool h64 = !access(MMAP_RND_COMPAT_PATH, F_OK);
/* supported 32-bit architecture must have 16 bits set */
if (set_mmap_rnd_bits_min(16, 16, h64)) {
- ret = 0;
+ return 0;
}
#elif defined(__mips__) || defined(__mips64__)
// TODO: add mips support b/27788820
- ret = 0;
+ return 0;
#else
LOG(ERROR) << "Unknown architecture";
#endif
- if (ret == -1) {
- LOG(ERROR) << "Unable to set adequate mmap entropy value!";
- security_failure();
- }
- return ret;
+ LOG(ERROR) << "Unable to set adequate mmap entropy value!";
+ security_failure();
+ return -1;
}
#define KPTR_RESTRICT_PATH "/proc/sys/kernel/kptr_restrict"