Ensure readdir(2) returns consistent (and unique) inode numbers. (Closes: #898287) (39e29c4e) · Commits · Reproducible Builds / disorderfs

disorderfs.cpp

+8 −5

Original line number	Diff line number	Diff line
		@@ -68,7 +68,7 @@ namespace {
		}

		int wrap (int retval) { return retval == -1 ? -errno : 0; }
		using Dirents = std::vector<std::string>;
		using Dirents = std::vector<std::pair<std::string, ino_t>>;

		// The libc versions of seteuid, etc. set the credentials for all threads.
		// We need to set credentials for a single thread only, so call the syscalls directly.
		@@ -270,7 +270,7 @@ int main (int argc, char** argv)

		// Add some of our own hard-coded FUSE options:
		fuse_opt_add_arg(&fargs, "-o");
		fuse_opt_add_arg(&fargs, "atomic_o_trunc,default_permissions"); // XXX: other mount options?
		fuse_opt_add_arg(&fargs, "atomic_o_trunc,default_permissions,use_ino"); // XXX: other mount options?
		if (config.multi_user) {
		fuse_opt_add_arg(&fargs, "-o");
		fuse_opt_add_arg(&fargs, "allow_other");
		@@ -429,7 +429,7 @@ int main (int argc, char** argv)
		struct dirent* dirent_p;
		int res;
		while ((res = readdir_r(d, &dirent_storage, &dirent_p)) == 0 && dirent_p) {
		dirents->emplace_back(dirent_p->d_name);
		dirents->emplace_back(std::make_pair(dirent_p->d_name, dirent_p->d_ino));
		}
		if (config.sort_dirents) {
		std::sort(dirents->begin(), dirents->end());
		@@ -447,14 +447,17 @@ int main (int argc, char** argv)
		};
		disorderfs_fuse_operations.readdir = [] (const char* path, void* buf, fuse_fill_dir_t filler, off_t offset, struct fuse_file_info* info) {
		Dirents& dirents = get_fuse_data<Dirents>(info);
		struct stat st;
		memset(&st, 0, sizeof(st));
		if (config.shuffle_dirents) {
		std::random_device rd;
		std::mt19937 g(rd());
		std::shuffle(dirents.begin(), dirents.end(), g);
		}

		for (const std::string& dirent : dirents) {
		if (filler(buf, dirent.c_str(), nullptr, 0) != 0) {
		for (const auto dirent : dirents) {
		st.st_ino = dirent.second;
		if (filler(buf, dirent.first.c_str(), &st, 0) != 0) {
		return -ENOMEM;
		}
		}

tests/inodes

0 → 100755

+87 −0

Original line number	Diff line number	Diff line
		#!/bin/sh

		. ./common

		TEMPDIR="$(mktemp -d -t inodes.XXXXXXXXXX)"

		trap "Unmount 2>/dev/null; rm -rf ${TEMPDIR}" EXIT

		Setup () {
		cat >${TEMPDIR}/inodes.cpp <<EOF
		#include <dirent.h>
		#include <fcntl.h>
		#include <stdio.h>
		#include <unistd.h>
		#include <stdlib.h>
		#include <string.h>
		#include <sys/stat.h>
		#include <sys/syscall.h>

		#include <map>
		#include <iostream>

		struct linux_dirent {
		unsigned long d_ino;
		off_t d_off;
		unsigned short d_reclen;
		char d_name[];
		};

		#define BUF_SIZE 1024

		void perror_and_die (const char* s)
		{
		std::perror(s);
		std::abort();
		}

		int
		main(int argc, char *argv[])
		{
		int fd, nread, ret = EXIT_SUCCESS;
		char buf[BUF_SIZE];
		struct stat st;
		const std::string dirname = argc > 1 ? argv[1] : ".";
		struct linux_dirent *d;
		std::map<ino_t, std::string> inodes;

		if ((fd = open(dirname.c_str(), O_RDONLY \| O_DIRECTORY)) == -1)
		perror_and_die("open");

		while ((nread = syscall(SYS_getdents, fd, buf, BUF_SIZE)) > 0) {
		for (int pos = 0; pos < nread; pos += d->d_reclen) {
		d = (struct linux_dirent *) (buf + pos);

		std::string filename = dirname + "/" + std::string(d->d_name);
		if (stat(filename.c_str(), &st) == -1)
		perror_and_die("stat");

		if (d->d_ino != st.st_ino) {
		std::cerr << filename << ": inode from getdents does not match stat: "
		<< d->d_ino << " != " << st.st_ino << std::endl;
		ret = EXIT_FAILURE;
		}

		if (inodes.find(d->d_ino) == inodes.end()) {
		inodes[d->d_ino] = filename;
		} else {
		std::cerr << filename << ": duplicate inode: " << d->d_ino
		<< " used by " << inodes[d->d_ino] << std::endl;
		ret = EXIT_FAILURE;
		}
		}
		}

		if (nread == -1)
		perror_and_die("open");

		exit(ret);
		}
		EOF
		g++ -Wall -o${TEMPDIR}/inodes ${TEMPDIR}/inodes.cpp \|\| Fail "Could not compile testcase"
		}

		Setup
		Mount
		${TEMPDIR}/inodes target \|\| Fail "inodes"
		Unmount