freebsd-dev/tests/sys/fs/fusefs/symlink.cc
Alan Somers 0bef4927ea fusefs: handle evil servers that return illegal inode numbers
* If during FUSE_CREATE, FUSE_MKDIR, etc the server returns the same
  inode number for the new file as for its parent directory, reject it.
  Previously this would triggers a recurse-on-non-recursive lock panic.

* If during FUSE_LINK the server returns a different inode number for
  the new name as for the old one, reject it.  Obviously, that can't be
  a hard link.

* If during FUSE_LOOKUP the server returns the same inode number for the
  new file as for its parent directory, reject it.  Nothing good can
  come of this.

PR:		263662
Reported by:	Robert Morris <rtm@lcs.mit.edu>
MFC after:	2 weeks
Reviewed by:	pfg
Differential Revision: https://reviews.freebsd.org/D35128
2022-05-12 14:32:26 -06:00

203 lines
5.9 KiB
C++

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2019 The FreeBSD Foundation
*
* This software was developed by BFF Storage Systems, LLC under sponsorship
* from the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
extern "C" {
#include <unistd.h>
}
#include "mockfs.hh"
#include "utils.hh"
using namespace testing;
class Symlink: public FuseTest {
public:
void expect_symlink(uint64_t ino, const char *target, const char *relpath)
{
EXPECT_CALL(*m_mock, process(
ResultOf([=](auto in) {
const char *name = (const char*)in.body.bytes;
const char *linkname = name + strlen(name) + 1;
return (in.header.opcode == FUSE_SYMLINK &&
(0 == strcmp(linkname, target)) &&
(0 == strcmp(name, relpath)));
}, Eq(true)),
_)
).WillOnce(Invoke(ReturnImmediate([=](auto in __unused, auto& out) {
SET_OUT_HEADER_LEN(out, entry);
out.body.entry.attr.mode = S_IFLNK | 0777;
out.body.entry.nodeid = ino;
out.body.entry.entry_valid = UINT64_MAX;
out.body.entry.attr_valid = UINT64_MAX;
})));
}
};
class Symlink_7_8: public FuseTest {
public:
virtual void SetUp() {
m_kernel_minor_version = 8;
FuseTest::SetUp();
}
void expect_symlink(uint64_t ino, const char *target, const char *relpath)
{
EXPECT_CALL(*m_mock, process(
ResultOf([=](auto in) {
const char *name = (const char*)in.body.bytes;
const char *linkname = name + strlen(name) + 1;
return (in.header.opcode == FUSE_SYMLINK &&
(0 == strcmp(linkname, target)) &&
(0 == strcmp(name, relpath)));
}, Eq(true)),
_)
).WillOnce(Invoke(ReturnImmediate([=](auto in __unused, auto& out) {
SET_OUT_HEADER_LEN(out, entry_7_8);
out.body.entry.attr.mode = S_IFLNK | 0777;
out.body.entry.nodeid = ino;
out.body.entry.entry_valid = UINT64_MAX;
out.body.entry.attr_valid = UINT64_MAX;
})));
}
};
/*
* A successful symlink should clear the parent directory's attribute cache,
* because the fuse daemon should update its mtime and ctime
*/
TEST_F(Symlink, clear_attr_cache)
{
const char FULLPATH[] = "mountpoint/src";
const char RELPATH[] = "src";
const char dst[] = "dst";
const uint64_t ino = 42;
struct stat sb;
EXPECT_LOOKUP(FUSE_ROOT_ID, RELPATH)
.WillOnce(Invoke(ReturnErrno(ENOENT)));
EXPECT_CALL(*m_mock, process(
ResultOf([=](auto in) {
return (in.header.opcode == FUSE_GETATTR &&
in.header.nodeid == FUSE_ROOT_ID);
}, Eq(true)),
_)
).Times(2)
.WillRepeatedly(Invoke(ReturnImmediate([=](auto i __unused, auto& out) {
SET_OUT_HEADER_LEN(out, attr);
out.body.attr.attr.ino = FUSE_ROOT_ID;
out.body.attr.attr.mode = S_IFDIR | 0755;
out.body.attr.attr_valid = UINT64_MAX;
})));
expect_symlink(ino, dst, RELPATH);
EXPECT_EQ(0, stat("mountpoint", &sb)) << strerror(errno);
EXPECT_EQ(0, symlink(dst, FULLPATH)) << strerror(errno);
EXPECT_EQ(0, stat("mountpoint", &sb)) << strerror(errno);
}
TEST_F(Symlink, enospc)
{
const char FULLPATH[] = "mountpoint/lnk";
const char RELPATH[] = "lnk";
const char dst[] = "dst";
EXPECT_LOOKUP(FUSE_ROOT_ID, RELPATH)
.WillOnce(Invoke(ReturnErrno(ENOENT)));
EXPECT_CALL(*m_mock, process(
ResultOf([=](auto in) {
const char *name = (const char*)in.body.bytes;
const char *linkname = name + strlen(name) + 1;
return (in.header.opcode == FUSE_SYMLINK &&
(0 == strcmp(linkname, dst)) &&
(0 == strcmp(name, RELPATH)));
}, Eq(true)),
_)
).WillOnce(Invoke(ReturnErrno(ENOSPC)));
EXPECT_EQ(-1, symlink(dst, FULLPATH));
EXPECT_EQ(ENOSPC, errno);
}
TEST_F(Symlink, ok)
{
const char FULLPATH[] = "mountpoint/src";
const char RELPATH[] = "src";
const char dst[] = "dst";
const uint64_t ino = 42;
EXPECT_LOOKUP(FUSE_ROOT_ID, RELPATH)
.WillOnce(Invoke(ReturnErrno(ENOENT)));
expect_symlink(ino, dst, RELPATH);
EXPECT_EQ(0, symlink(dst, FULLPATH)) << strerror(errno);
}
/*
* Nothing bad should happen if the server returns the parent's inode number
* for the newly created symlink. Regression test for bug 263662.
* https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=263662
*/
TEST_F(Symlink, parent_ino)
{
const char FULLPATH[] = "mountpoint/parent/src";
const char PPATH[] = "parent";
const char RELPATH[] = "src";
const char dst[] = "dst";
const uint64_t ino = 42;
expect_lookup(PPATH, ino, S_IFDIR | 0755, 0, 1);
EXPECT_LOOKUP(ino, RELPATH)
.WillOnce(Invoke(ReturnErrno(ENOENT)));
expect_symlink(ino, dst, RELPATH);
EXPECT_EQ(-1, symlink(dst, FULLPATH));
EXPECT_EQ(EIO, errno);
}
TEST_F(Symlink_7_8, ok)
{
const char FULLPATH[] = "mountpoint/src";
const char RELPATH[] = "src";
const char dst[] = "dst";
const uint64_t ino = 42;
EXPECT_LOOKUP(FUSE_ROOT_ID, RELPATH)
.WillOnce(Invoke(ReturnErrno(ENOENT)));
expect_symlink(ino, dst, RELPATH);
EXPECT_EQ(0, symlink(dst, FULLPATH)) << strerror(errno);
}