diff options
| -rw-r--r-- | pkg/abi/linux/fuse.go | 131 | ||||
| -rw-r--r-- | pkg/sentry/fsimpl/fuse/connection.go | 8 | ||||
| -rw-r--r-- | pkg/sentry/fsimpl/fuse/directory.go | 54 | ||||
| -rw-r--r-- | pkg/sentry/fsimpl/fuse/file.go | 6 | ||||
| -rw-r--r-- | pkg/sentry/fsimpl/kernfs/kernfs.go | 2 | ||||
| -rw-r--r-- | pkg/sentry/vfs/file_description_impl_util.go | 2 | ||||
| -rw-r--r-- | test/fuse/BUILD | 6 | ||||
| -rw-r--r-- | test/fuse/linux/BUILD | 14 | ||||
| -rw-r--r-- | test/fuse/linux/readdir_test.cc | 188 |
9 files changed, 403 insertions, 8 deletions
diff --git a/pkg/abi/linux/fuse.go b/pkg/abi/linux/fuse.go index c75debb8c..e7b5f45de 100644 --- a/pkg/abi/linux/fuse.go +++ b/pkg/abi/linux/fuse.go @@ -14,7 +14,10 @@ package linux -import "gvisor.dev/gvisor/tools/go_marshal/marshal" +import ( + "gvisor.dev/gvisor/tools/go_marshal/marshal" + "gvisor.dev/gvisor/tools/go_marshal/primitive" +) // +marshal type FUSEOpcode uint32 @@ -186,9 +189,9 @@ const ( // Constants relevant to FUSE operations. const ( - FUSE_NAME_MAX = 1024 - FUSE_PAGE_SIZE = 4096 - FUSE_DIRENT_ALIGN = 8 + FUSE_NAME_MAX = 1024 + FUSE_PAGE_SIZE = 4096 + FUSE_DIRENT_ALIGN = 8 ) // FUSEInitIn is the request sent by the kernel to the daemon, @@ -595,3 +598,123 @@ func (r *FUSERmDirIn) SizeBytes() int { func (r *FUSERmDirIn) UnmarshalUnsafe(src []byte) { r.Name = string(src) } + +// FUSEDirents is a list of Dirents received from the FUSE daemon server. +// It is used for FUSE_READDIR. +// +// Dynamically-sized objects cannot be marshalled. +type FUSEDirents struct { + marshal.StubMarshallable + + Dirents []*FUSEDirent +} + +// FUSEDirent is a Dirent received from the FUSE daemon server. +// It is used for FUSE_READDIR. +// +// Dynamically-sized objects cannot be marshalled. +type FUSEDirent struct { + marshal.StubMarshallable + + // Meta contains all the static fields of FUSEDirent. + Meta FUSEDirentMeta + + // Name is the filename of the dirent. + Name string +} + +// FUSEDirentMeta contains all the static fields of FUSEDirent. +// It is used for FUSE_READDIR. +// +// +marshal +type FUSEDirentMeta struct { + // Inode of the dirent. + Ino uint64 + + // Offset of the dirent. + Off uint64 + + // NameLen is the length of the dirent name. + NameLen uint32 + + // Type of the dirent. + Type uint32 +} + +// MarshalUnsafe serializes FUSEDirents to the dst buffer. +func (r *FUSEDirents) MarshalUnsafe(dst []byte) { + for _, dirent := range r.Dirents { + dirent.MarshalUnsafe(dst) + dst = dst[dirent.SizeBytes():] + } +} + +// SizeBytes is the size of the memory representation of FUSEDirents. +func (r *FUSEDirents) SizeBytes() int { + var sizeBytes int + for _, dirent := range r.Dirents { + sizeBytes += dirent.SizeBytes() + } + + return sizeBytes +} + +// UnmarshalUnsafe deserializes FUSEDirents from the src buffer. +func (r *FUSEDirents) UnmarshalUnsafe(src []byte) { + for { + if len(src) <= (*FUSEDirentMeta)(nil).SizeBytes() { + break + } + + // Its unclear how many dirents there are in src. Each dirent is dynamically + // sized and so we can't make assumptions about how many dirents we can allocate. + if r.Dirents == nil { + r.Dirents = make([]*FUSEDirent, 0) + } + + // We have to allocate a struct for each dirent - there must be a better way + // to do this. Linux allocates 1 page to store all the dirents and then + // simply reads them from the page. + var dirent FUSEDirent + dirent.UnmarshalUnsafe(src) + r.Dirents = append(r.Dirents, &dirent) + + src = src[dirent.SizeBytes():] + } +} + +// MarshalUnsafe serializes FUSEDirent to the dst buffer. +func (r *FUSEDirent) MarshalUnsafe(dst []byte) { + r.Meta.MarshalUnsafe(dst) + dst = dst[r.Meta.SizeBytes():] + + name := primitive.ByteSlice(r.Name) + name.MarshalUnsafe(dst) +} + +// SizeBytes is the size of the memory representation of FUSEDirent. +func (r *FUSEDirent) SizeBytes() int { + dataSize := r.Meta.SizeBytes() + len(r.Name) + + // Each Dirent must be padded such that its size is a multiple + // of FUSE_DIRENT_ALIGN. Similar to the fuse dirent alignment + // in linux/fuse.h. + return (dataSize + (FUSE_DIRENT_ALIGN - 1)) & ^(FUSE_DIRENT_ALIGN - 1) +} + +// UnmarshalUnsafe deserializes FUSEDirent from the src buffer. +func (r *FUSEDirent) UnmarshalUnsafe(src []byte) { + r.Meta.UnmarshalUnsafe(src) + src = src[r.Meta.SizeBytes():] + + if r.Meta.NameLen > FUSE_NAME_MAX { + // The name is too long and therefore invalid. We don't + // need to unmarshal the name since it'll be thrown away. + return + } + + buf := make([]byte, r.Meta.NameLen) + name := primitive.ByteSlice(buf) + name.UnmarshalUnsafe(src[:r.Meta.NameLen]) + r.Name = string(name) +} diff --git a/pkg/sentry/fsimpl/fuse/connection.go b/pkg/sentry/fsimpl/fuse/connection.go index 236165652..133306158 100644 --- a/pkg/sentry/fsimpl/fuse/connection.go +++ b/pkg/sentry/fsimpl/fuse/connection.go @@ -21,6 +21,8 @@ import ( "sync/atomic" "syscall" + "gvisor.dev/gvisor/tools/go_marshal/marshal" + "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/log" @@ -352,6 +354,12 @@ func (r *Response) UnmarshalPayload(m marshal.Marshallable) error { return fmt.Errorf("payload too small. Minimum data lenth required: %d, but got data length %d", wantDataLen, haveDataLen) } + // The response data is empty unless there is some payload. And so, doesn't + // need to be unmarshalled. + if r.data == nil { + return nil + } + m.UnmarshalUnsafe(r.data[hdrLen:]) return nil } diff --git a/pkg/sentry/fsimpl/fuse/directory.go b/pkg/sentry/fsimpl/fuse/directory.go index 44d41712a..8c59680e8 100644 --- a/pkg/sentry/fsimpl/fuse/directory.go +++ b/pkg/sentry/fsimpl/fuse/directory.go @@ -15,7 +15,12 @@ package fuse import ( + "sync/atomic" + + "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/usermem" @@ -49,3 +54,52 @@ func (directoryFD) PWrite(ctx context.Context, src usermem.IOSequence, offset in func (directoryFD) Write(ctx context.Context, src usermem.IOSequence, opts vfs.WriteOptions) (int64, error) { return 0, syserror.EISDIR } + +// IterDirents implements FileDescriptionImpl.IterDirents. +func (dir *directoryFD) IterDirents(ctx context.Context, callback vfs.IterDirentsCallback) error { + fusefs := dir.inode().fs + task, creds := kernel.TaskFromContext(ctx), auth.CredentialsFromContext(ctx) + + in := linux.FUSEReadIn{ + Fh: dir.Fh, + Offset: uint64(atomic.LoadInt64(&dir.off)), + Size: linux.FUSE_PAGE_SIZE, + Flags: dir.statusFlags(), + } + + /// TODO(gVisor.dev/issue/3404): Support FUSE_READDIRPLUS. + req, err := fusefs.conn.NewRequest(creds, uint32(task.ThreadID()), dir.inode().NodeID, linux.FUSE_READDIR, &in) + if err != nil { + return err + } + + res, err := fusefs.conn.Call(task, req) + if err != nil { + return err + } + if err := res.Error(); err != nil { + return err + } + + var out linux.FUSEDirents + if err := res.UnmarshalPayload(&out); err != nil { + return err + } + + for _, fuseDirent := range out.Dirents { + nextOff := int64(fuseDirent.Meta.Off) + 1 + dirent := vfs.Dirent{ + Name: fuseDirent.Name, + Type: uint8(fuseDirent.Meta.Type), + Ino: fuseDirent.Meta.Ino, + NextOff: nextOff, + } + + if err := callback.Handle(dirent); err != nil { + return err + } + atomic.StoreInt64(&dir.off, nextOff) + } + + return nil +} diff --git a/pkg/sentry/fsimpl/fuse/file.go b/pkg/sentry/fsimpl/fuse/file.go index 01d20caf6..186ec2362 100644 --- a/pkg/sentry/fsimpl/fuse/file.go +++ b/pkg/sentry/fsimpl/fuse/file.go @@ -42,6 +42,9 @@ type fileDescription struct { // OpenFlag is the flag returned by open. OpenFlag uint32 + + // off is the file offset. + off int64 } func (fd *fileDescription) dentry() *kernfs.Dentry { @@ -119,5 +122,6 @@ func (fd *fileDescription) Stat(ctx context.Context, opts vfs.StatOptions) (linu // SetStat implements FileDescriptionImpl.SetStat. func (fd *fileDescription) SetStat(ctx context.Context, opts vfs.SetStatOptions) error { - return nil + creds := auth.CredentialsFromContext(ctx) + return fd.inode().SetStat(ctx, fd.inode().fs.VFSFilesystem(), creds, opts) } diff --git a/pkg/sentry/fsimpl/kernfs/kernfs.go b/pkg/sentry/fsimpl/kernfs/kernfs.go index f656e2a8b..61189af25 100644 --- a/pkg/sentry/fsimpl/kernfs/kernfs.go +++ b/pkg/sentry/fsimpl/kernfs/kernfs.go @@ -425,7 +425,7 @@ type inodeDynamicLookup interface { Valid(ctx context.Context) bool // IterDirents is used to iterate over dynamically created entries. It invokes - // cb on each entry in the directory represented by the FileDescription. + // cb on each entry in the directory represented by the Inode. // 'offset' is the offset for the entire IterDirents call, which may include // results from the caller (e.g. "." and ".."). 'relOffset' is the offset // inside the entries returned by this IterDirents invocation. In other words, diff --git a/pkg/sentry/vfs/file_description_impl_util.go b/pkg/sentry/vfs/file_description_impl_util.go index 68b80a951..2b668fd89 100644 --- a/pkg/sentry/vfs/file_description_impl_util.go +++ b/pkg/sentry/vfs/file_description_impl_util.go @@ -107,7 +107,7 @@ func (FileDescriptionDefaultImpl) Write(ctx context.Context, src usermem.IOSeque // file_operations::iterate == file_operations::iterate_shared == NULL in // Linux. func (FileDescriptionDefaultImpl) IterDirents(ctx context.Context, cb IterDirentsCallback) error { - return syserror.ENOTDIR + return syserror.ENOSYS } // Seek implements FileDescriptionImpl.Seek analogously to diff --git a/test/fuse/BUILD b/test/fuse/BUILD index 30d2a871f..a1b29aa33 100644 --- a/test/fuse/BUILD +++ b/test/fuse/BUILD @@ -43,7 +43,11 @@ syscall_test( ) syscall_test( + fuse = "True", test = "//test/fuse/linux:rmdir_test", - vfs2 = "True", +) + +syscall_test( fuse = "True", + test = "//test/fuse/linux:readdir_test", ) diff --git a/test/fuse/linux/BUILD b/test/fuse/linux/BUILD index 159428fce..23c9fba31 100644 --- a/test/fuse/linux/BUILD +++ b/test/fuse/linux/BUILD @@ -112,6 +112,20 @@ cc_binary( ], ) +cc_binary( + name = "readdir_test", + testonly = 1, + srcs = ["readdir_test.cc"], + deps = [ + gtest, + ":fuse_base", + "//test/util:fs_util", + "//test/util:fuse_util", + "//test/util:test_main", + "//test/util:test_util", + ], +) + cc_library( name = "fuse_base", testonly = 1, diff --git a/test/fuse/linux/readdir_test.cc b/test/fuse/linux/readdir_test.cc new file mode 100644 index 000000000..17fb630ee --- /dev/null +++ b/test/fuse/linux/readdir_test.cc @@ -0,0 +1,188 @@ +// 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/fuse_util.h" +#include "test/util/test_util.h" + +#define FUSE_NAME_OFFSET offsetof(struct fuse_dirent, name) +#define FUSE_DIRENT_ALIGN(x) \ + (((x) + sizeof(uint64_t) - 1) & ~(sizeof(uint64_t) - 1)) +#define FUSE_DIRENT_SIZE(d) FUSE_DIRENT_ALIGN(FUSE_NAME_OFFSET + (d)->namelen) + +namespace gvisor { +namespace testing { + +namespace { + +class ReaddirTest : public FuseTest { + public: + void fill_fuse_dirent(char *buf, const char *name) { + size_t namelen = strlen(name); + size_t entlen = FUSE_NAME_OFFSET + namelen; + size_t entlen_padded = FUSE_DIRENT_ALIGN(entlen); + struct fuse_dirent *dirent; + + dirent = reinterpret_cast<struct fuse_dirent *>(buf); + dirent->namelen = namelen; + memcpy(dirent->name, name, namelen); + memset(dirent->name + namelen, 0, entlen_padded - entlen); + } + + protected: + const std::string test_dir_name_ = "test_dir"; +}; + +TEST_F(ReaddirTest, SingleEntry) { + const std::string test_dir_path = + JoinPath(mount_point_.path().c_str(), test_dir_name_); + + // We need to make sure the test dir is a directory that can be found. + mode_t expected_mode = + S_IFDIR | S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH; + struct fuse_attr dir_attr = { + .ino = 1, + .size = 512, + .blocks = 4, + .mode = expected_mode, + .blksize = 4096, + }; + struct fuse_out_header stat_header = { + .len = sizeof(struct fuse_out_header) + sizeof(struct fuse_attr_out), + }; + + struct fuse_attr_out stat_payload = { + .attr_valid_nsec = 2, + .attr = dir_attr, + }; + + // We need to make sure the test dir is a directory that can be found. + struct fuse_out_header lookup_header = { + .len = sizeof(struct fuse_out_header) + sizeof(struct fuse_entry_out), + }; + struct fuse_entry_out lookup_payload = { + .nodeid = 1, + .entry_valid = true, + .attr_valid = true, + .attr = dir_attr, + }; + + struct fuse_out_header open_header = { + .len = sizeof(struct fuse_out_header) + sizeof(struct fuse_open_out), + }; + struct fuse_open_out open_payload = { + .fh = 1, + }; + auto iov_out = FuseGenerateIovecs(lookup_header, lookup_payload); + SetServerResponse(FUSE_LOOKUP, iov_out); + + iov_out = FuseGenerateIovecs(open_header, open_payload); + SetServerResponse(FUSE_OPENDIR, iov_out); + + iov_out = FuseGenerateIovecs(stat_header, stat_payload); + SetServerResponse(FUSE_GETATTR, iov_out); + + DIR *dir = opendir(test_dir_path.c_str()); + + // The opendir command makes three syscalls. Lookup the dir file, stat it and + // open. + // We don't need to inspect those headers in this test. + SkipServerActualRequest(); // LOOKUP. + SkipServerActualRequest(); // GETATTR. + SkipServerActualRequest(); // OPENDIR. + + // Readdir test code. + std::string dot = "."; + std::string dot_dot = ".."; + std::string test_file = "testFile"; + + // Figure out how many dirents to send over and allocate them appropriately. + // Each dirent has a dynamic name and a static metadata part. The dirent size + // is aligned to being a multiple of 8. + size_t dot_file_dirent_size = + FUSE_DIRENT_ALIGN(dot.length() + FUSE_NAME_OFFSET); + size_t dot_dot_file_dirent_size = + FUSE_DIRENT_ALIGN(dot_dot.length() + FUSE_NAME_OFFSET); + size_t test_file_dirent_size = + FUSE_DIRENT_ALIGN(test_file.length() + FUSE_NAME_OFFSET); + + // Create an appropriately sized payload. + size_t readdir_payload_size = + test_file_dirent_size + dot_file_dirent_size + dot_dot_file_dirent_size; + char readdir_payload[readdir_payload_size]; + + fill_fuse_dirent(readdir_payload, dot.c_str()); + fill_fuse_dirent(readdir_payload + dot_file_dirent_size, dot_dot.c_str()); + fill_fuse_dirent( + readdir_payload + dot_file_dirent_size + dot_dot_file_dirent_size, + test_file.c_str()); + + std::vector<char> readdir_payload_vec(readdir_payload, + readdir_payload + readdir_payload_size); + struct fuse_out_header readdir_header = { + .len = uint32_t(sizeof(struct fuse_out_header) + sizeof(readdir_payload)), + }; + struct fuse_out_header readdir_header_break = { + .len = uint32_t(sizeof(struct fuse_out_header)), + }; + + iov_out = FuseGenerateIovecs(readdir_header, readdir_payload_vec); + SetServerResponse(FUSE_READDIR, iov_out); + + iov_out = FuseGenerateIovecs(readdir_header_break); + SetServerResponse(FUSE_READDIR, iov_out); + + struct dirent *entry; + entry = readdir(dir); + EXPECT_EQ(std::string(entry->d_name), dot); + + entry = readdir(dir); + EXPECT_EQ(std::string(entry->d_name), dot_dot); + + entry = readdir(dir); + EXPECT_EQ(std::string(entry->d_name), test_file); + + entry = readdir(dir); + EXPECT_TRUE((entry == NULL)); + + SkipServerActualRequest(); // READDIR. + SkipServerActualRequest(); // READDIR with no data. + + // Clean up. + closedir(dir); + + struct fuse_in_header in_header; + struct fuse_release_in in_payload; + + auto iov_in = FuseGenerateIovecs(in_header, in_payload); + GetServerActualRequest(iov_in); + EXPECT_EQ(in_header.len, sizeof(in_header) + sizeof(in_payload)); + EXPECT_EQ(in_header.opcode, FUSE_RELEASEDIR); +} + +} // namespace + +} // namespace testing +} // namespace gvisor
\ No newline at end of file |