diff options
| -rw-r--r-- | pkg/abi/linux/fuse.go | 42 | ||||
| -rw-r--r-- | pkg/sentry/fsimpl/fuse/fusefs.go | 18 | ||||
| -rw-r--r-- | test/fuse/BUILD | 4 | ||||
| -rw-r--r-- | test/fuse/linux/BUILD | 17 | ||||
| -rw-r--r-- | test/fuse/linux/create_test.cc | 128 |
5 files changed, 208 insertions, 1 deletions
diff --git a/pkg/abi/linux/fuse.go b/pkg/abi/linux/fuse.go index ed40df564..adc04dbcc 100644 --- a/pkg/abi/linux/fuse.go +++ b/pkg/abi/linux/fuse.go @@ -445,6 +445,48 @@ type FUSEReleaseIn struct { LockOwner uint64 } +// FUSECreateMeta contains all the static fields of FUSECreateIn, +// which is used for FUSE_CREATE. +// +// +marshal +type FUSECreateMeta struct { + // Flags of the creating file. + Flags uint32 + + // Mode is the mode of the creating file. + Mode uint32 + + // Umask is the current file mode creation mask. + Umask uint32 + _ uint32 +} + +// FUSECreateIn contains all the arguments sent by the kernel to the daemon, to +// atomically create and open a new regular file. +// +// Dynamically-sized objects cannot be marshalled. +type FUSECreateIn struct { + marshal.StubMarshallable + + // CreateMeta contains mode, rdev and umash field for FUSE_MKNODS. + CreateMeta FUSECreateMeta + + // Name is the name of the node to create. + Name string +} + +// MarshalBytes serializes r.CreateMeta and r.Name to the dst buffer. +func (r *FUSECreateIn) MarshalBytes(buf []byte) { + r.CreateMeta.MarshalBytes(buf[:r.CreateMeta.SizeBytes()]) + copy(buf[r.CreateMeta.SizeBytes():], r.Name) +} + +// SizeBytes is the size of the memory representation of FUSECreateIn. +// 1 extra byte for null-terminated string. +func (r *FUSECreateIn) SizeBytes() int { + return r.CreateMeta.SizeBytes() + len(r.Name) + 1 +} + // FUSEMknodMeta contains all the static fields of FUSEMknodIn, // which is used for FUSE_MKNOD. // diff --git a/pkg/sentry/fsimpl/fuse/fusefs.go b/pkg/sentry/fsimpl/fuse/fusefs.go index e1bbb4b52..cfae9ed0d 100644 --- a/pkg/sentry/fsimpl/fuse/fusefs.go +++ b/pkg/sentry/fsimpl/fuse/fusefs.go @@ -392,6 +392,24 @@ func (inode) Valid(ctx context.Context) bool { return true } +// NewFile implements kernfs.Inode.NewFile. +func (i *inode) NewFile(ctx context.Context, name string, opts vfs.OpenOptions) (*vfs.Dentry, error) { + kernelTask := kernel.TaskFromContext(ctx) + if kernelTask == nil { + log.Warningf("fusefs.Inode.NewFile: couldn't get kernel task from context", i.NodeID) + return nil, syserror.EINVAL + } + in := linux.FUSECreateIn{ + CreateMeta: linux.FUSECreateMeta{ + Flags: opts.Flags, + Mode: uint32(opts.Mode) | linux.S_IFREG, + Umask: uint32(kernelTask.FSContext().Umask()), + }, + Name: name, + } + return i.newEntry(ctx, name, linux.S_IFREG, linux.FUSE_CREATE, &in) +} + // NewNode implements kernfs.Inode.NewNode. func (i *inode) NewNode(ctx context.Context, name string, opts vfs.MknodOptions) (*vfs.Dentry, error) { in := linux.FUSEMknodIn{ diff --git a/test/fuse/BUILD b/test/fuse/BUILD index 02498b3a1..1a6b5b516 100644 --- a/test/fuse/BUILD +++ b/test/fuse/BUILD @@ -52,6 +52,10 @@ syscall_test( test = "//test/fuse/linux:readdir_test", ) +syscall_test( + fuse = "True", + test = "//test/fuse/linux:create_test", +) syscall_test( size = "large", diff --git a/test/fuse/linux/BUILD b/test/fuse/linux/BUILD index 23c9fba31..2bb956af9 100644 --- a/test/fuse/linux/BUILD +++ b/test/fuse/linux/BUILD @@ -152,4 +152,19 @@ cc_binary( "//test/util:test_main", "//test/util:test_util", ], -)
\ No newline at end of file +) + +cc_binary( + name = "create_test", + testonly = 1, + srcs = ["create_test.cc"], + deps = [ + gtest, + ":fuse_base", + "//test/util:fs_util", + "//test/util:fuse_util", + "//test/util:temp_umask", + "//test/util:test_main", + "//test/util:test_util", + ], +) diff --git a/test/fuse/linux/create_test.cc b/test/fuse/linux/create_test.cc new file mode 100644 index 000000000..9a0219a58 --- /dev/null +++ b/test/fuse/linux/create_test.cc @@ -0,0 +1,128 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +#include <errno.h> +#include <fcntl.h> +#include <linux/fuse.h> +#include <sys/stat.h> +#include <sys/statfs.h> +#include <sys/types.h> +#include <unistd.h> + +#include <string> + +#include "gtest/gtest.h" +#include "test/fuse/linux/fuse_base.h" +#include "test/util/fs_util.h" +#include "test/util/fuse_util.h" +#include "test/util/temp_umask.h" +#include "test/util/test_util.h" + +namespace gvisor { +namespace testing { + +namespace { + +class CreateTest : public FuseTest { + protected: + const std::string test_file_name_ = "test_file"; + const mode_t mode = S_IFREG | S_IRWXU | S_IRWXG | S_IRWXO; +}; + +TEST_F(CreateTest, CreateFile) { + const std::string test_file_path = + JoinPath(mount_point_.path().c_str(), test_file_name_); + + // Ensure the file doesn't exist. + struct fuse_out_header out_header = { + .len = sizeof(struct fuse_out_header), + .error = -ENOENT, + }; + auto iov_out = FuseGenerateIovecs(out_header); + SetServerResponse(FUSE_LOOKUP, iov_out); + + // creat(2) is equal to open(2) with open_flags O_CREAT | O_WRONLY | O_TRUNC. + const mode_t new_mask = S_IWGRP | S_IWOTH; + const int open_flags = O_CREAT | O_WRONLY | O_TRUNC; + out_header.error = 0; + out_header.len = sizeof(struct fuse_out_header) + + sizeof(struct fuse_entry_out) + sizeof(struct fuse_open_out); + struct fuse_entry_out entry_payload = DefaultEntryOut(mode & ~new_mask, 2); + struct fuse_open_out out_payload = { + .fh = 1, + .open_flags = open_flags, + }; + iov_out = FuseGenerateIovecs(out_header, entry_payload, out_payload); + SetServerResponse(FUSE_CREATE, iov_out); + + // kernfs generates a successive FUSE_OPEN after the file is created. Linux's + // fuse kernel module will not send this FUSE_OPEN after creat(2). + out_header.len = + sizeof(struct fuse_out_header) + sizeof(struct fuse_open_out); + iov_out = FuseGenerateIovecs(out_header, out_payload); + SetServerResponse(FUSE_OPEN, iov_out); + + int fd; + TempUmask mask(new_mask); + EXPECT_THAT(fd = creat(test_file_path.c_str(), mode), SyscallSucceeds()); + EXPECT_THAT(fcntl(fd, F_GETFL), + SyscallSucceedsWithValue(open_flags & O_ACCMODE)); + + struct fuse_in_header in_header; + struct fuse_create_in in_payload; + std::vector<char> name(test_file_name_.size() + 1); + auto iov_in = FuseGenerateIovecs(in_header, in_payload, name); + + // Skip the request of FUSE_LOOKUP. + SkipServerActualRequest(); + + // Get the first FUSE_CREATE. + GetServerActualRequest(iov_in); + EXPECT_EQ(in_header.len, sizeof(in_header) + sizeof(in_payload) + + test_file_name_.size() + 1); + EXPECT_EQ(in_header.opcode, FUSE_CREATE); + EXPECT_EQ(in_payload.flags, open_flags); + EXPECT_EQ(in_payload.mode, mode & ~new_mask); + EXPECT_EQ(in_payload.umask, new_mask); + EXPECT_EQ(std::string(name.data()), test_file_name_); + + // Get the successive FUSE_OPEN. + struct fuse_open_in in_payload_open; + iov_in = FuseGenerateIovecs(in_header, in_payload_open); + GetServerActualRequest(iov_in); + EXPECT_EQ(in_header.len, sizeof(in_header) + sizeof(in_payload_open)); + EXPECT_EQ(in_header.opcode, FUSE_OPEN); + EXPECT_EQ(in_payload_open.flags, open_flags & O_ACCMODE); + + EXPECT_THAT(close(fd), SyscallSucceeds()); + // Skip the FUSE_RELEASE. + SkipServerActualRequest(); +} + +TEST_F(CreateTest, CreateFileAlreadyExists) { + const std::string test_file_path = + JoinPath(mount_point_.path().c_str(), test_file_name_); + + const int open_flags = O_CREAT | O_EXCL; + + SetServerInodeLookup(test_file_name_); + + EXPECT_THAT(open(test_file_path.c_str(), mode, open_flags), + SyscallFailsWithErrno(EEXIST)); +} + +} // namespace + +} // namespace testing +} // namespace gvisor |