Straighten out do_mkdir
Use lstat(), and then make only the system calls needed to fix the
directory up.
Bug: 140027478
Test: boots twice, no worrying log messages.
Change-Id: I1c1445baae3ec1c1ce17626ede388aa04d5f7781
diff --git a/init/builtins.cpp b/init/builtins.cpp
index fb10a87..d6b6ee8 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -357,51 +357,64 @@
// mkdir <path> [mode] [owner] [group]
static Result<void> do_mkdir(const BuiltinArguments& args) {
mode_t mode = 0755;
- if (args.size() >= 3) {
- mode = std::strtoul(args[2].c_str(), 0, 8);
- }
+ Result<uid_t> uid = -1;
+ Result<gid_t> gid = -1;
- if (!make_dir(args[1], mode)) {
- /* chmod in case the directory already exists */
- if (errno == EEXIST) {
- if (fchmodat(AT_FDCWD, args[1].c_str(), mode, AT_SYMLINK_NOFOLLOW) == -1) {
- return ErrnoError() << "fchmodat() failed";
- }
- } else {
- return ErrnoErrorIgnoreEnoent() << "mkdir() failed";
- }
- }
-
- if (args.size() >= 4) {
- auto uid = DecodeUid(args[3]);
- if (!uid) {
- return Error() << "Unable to decode UID for '" << args[3] << "': " << uid.error();
- }
- Result<gid_t> gid = -1;
-
- if (args.size() == 5) {
+ switch (args.size()) {
+ case 5:
gid = DecodeUid(args[4]);
if (!gid) {
return Error() << "Unable to decode GID for '" << args[4] << "': " << gid.error();
}
- }
-
- if (lchown(args[1].c_str(), *uid, *gid) == -1) {
- return ErrnoError() << "lchown failed";
- }
-
- /* chown may have cleared S_ISUID and S_ISGID, chmod again */
- if (mode & (S_ISUID | S_ISGID)) {
- if (fchmodat(AT_FDCWD, args[1].c_str(), mode, AT_SYMLINK_NOFOLLOW) == -1) {
- return ErrnoError() << "fchmodat failed";
+ FALLTHROUGH_INTENDED;
+ case 4:
+ uid = DecodeUid(args[3]);
+ if (!uid) {
+ return Error() << "Unable to decode UID for '" << args[3] << "': " << uid.error();
}
+ FALLTHROUGH_INTENDED;
+ case 3:
+ mode = std::strtoul(args[2].c_str(), 0, 8);
+ FALLTHROUGH_INTENDED;
+ case 2:
+ break;
+ default:
+ return Error() << "Unexpected argument count: " << args.size();
+ }
+ std::string target = args[1];
+ struct stat mstat;
+ if (lstat(target.c_str(), &mstat) != 0) {
+ if (errno != ENOENT) {
+ return ErrnoError() << "lstat() failed on " << target;
+ }
+ if (!make_dir(target, mode)) {
+ return ErrnoErrorIgnoreEnoent() << "mkdir() failed on " << target;
+ }
+ if (lstat(target.c_str(), &mstat) != 0) {
+ return ErrnoError() << "lstat() failed on new " << target;
}
}
-
+ if (!S_ISDIR(mstat.st_mode)) {
+ return Error() << "Not a directory on " << target;
+ }
+ bool needs_chmod = (mstat.st_mode & ~S_IFMT) != mode;
+ if ((*uid != static_cast<uid_t>(-1) && *uid != mstat.st_uid) ||
+ (*gid != static_cast<gid_t>(-1) && *gid != mstat.st_gid)) {
+ if (lchown(target.c_str(), *uid, *gid) == -1) {
+ return ErrnoError() << "lchown failed on " << target;
+ }
+ // chown may have cleared S_ISUID and S_ISGID, chmod again
+ needs_chmod = true;
+ }
+ if (needs_chmod) {
+ if (fchmodat(AT_FDCWD, target.c_str(), mode, AT_SYMLINK_NOFOLLOW) == -1) {
+ return ErrnoError() << "fchmodat() failed on " << target;
+ }
+ }
if (fscrypt_is_native()) {
- if (fscrypt_set_directory_policy(args[1])) {
+ if (fscrypt_set_directory_policy(target)) {
return reboot_into_recovery(
- {"--prompt_and_wipe_data", "--reason=set_policy_failed:"s + args[1]});
+ {"--prompt_and_wipe_data", "--reason=set_policy_failed:"s + target});
}
}
return {};