diff options
Diffstat (limited to 'pkg')
-rw-r--r-- | pkg/abi/linux/linux_abi_autogen_unsafe.go | 18 | ||||
-rw-r--r-- | pkg/sentry/fsimpl/gofer/gofer.go | 150 | ||||
-rw-r--r-- | pkg/sentry/fsimpl/gofer/time.go | 3 |
3 files changed, 100 insertions, 71 deletions
diff --git a/pkg/abi/linux/linux_abi_autogen_unsafe.go b/pkg/abi/linux/linux_abi_autogen_unsafe.go index 74feacefb..2ed371bcf 100644 --- a/pkg/abi/linux/linux_abi_autogen_unsafe.go +++ b/pkg/abi/linux/linux_abi_autogen_unsafe.go @@ -150,7 +150,7 @@ func (s *Statx) Packed() bool { // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe. func (s *Statx) MarshalUnsafe(dst []byte) { - if s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() && s.Atime.Packed() { + if s.Ctime.Packed() && s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() { safecopy.CopyIn(dst, unsafe.Pointer(s)) } else { // Type Statx doesn't have a packed layout in memory, fallback to MarshalBytes. @@ -171,7 +171,7 @@ func (s *Statx) UnmarshalUnsafe(src []byte) { // CopyOutN implements marshal.Marshallable.CopyOutN. //go:nosplit func (s *Statx) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) { - if !s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() { + if !s.Ctime.Packed() && s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() { // Type Statx doesn't have a packed layout in memory, fall back to MarshalBytes. buf := task.CopyScratchBuffer(s.SizeBytes()) // escapes: okay. s.MarshalBytes(buf) // escapes: fallback. @@ -227,7 +227,7 @@ func (s *Statx) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) { // WriteTo implements io.WriterTo.WriteTo. func (s *Statx) WriteTo(w io.Writer) (int64, error) { - if !s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() { + if !s.Ctime.Packed() && s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() { // Type Statx doesn't have a packed layout in memory, fall back to MarshalBytes. buf := make([]byte, s.SizeBytes()) s.MarshalBytes(buf) @@ -635,7 +635,7 @@ func (f *FUSEHeaderIn) MarshalUnsafe(dst []byte) { // UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe. func (f *FUSEHeaderIn) UnmarshalUnsafe(src []byte) { - if f.Opcode.Packed() && f.Unique.Packed() { + if f.Unique.Packed() && f.Opcode.Packed() { safecopy.CopyOut(unsafe.Pointer(f), src) } else { // Type FUSEHeaderIn doesn't have a packed layout in memory, fallback to UnmarshalBytes. @@ -676,7 +676,7 @@ func (f *FUSEHeaderIn) CopyOut(task marshal.Task, addr usermem.Addr) (int, error // CopyIn implements marshal.Marshallable.CopyIn. //go:nosplit func (f *FUSEHeaderIn) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) { - if !f.Unique.Packed() && f.Opcode.Packed() { + if !f.Opcode.Packed() && f.Unique.Packed() { // Type FUSEHeaderIn doesn't have a packed layout in memory, fall back to UnmarshalBytes. buf := task.CopyScratchBuffer(f.SizeBytes()) // escapes: okay. length, err := task.CopyInBytes(addr, buf) // escapes: okay. @@ -1712,7 +1712,7 @@ func (i *IPTEntry) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) { // WriteTo implements io.WriterTo.WriteTo. func (i *IPTEntry) WriteTo(w io.Writer) (int64, error) { - if !i.Counters.Packed() && i.IP.Packed() { + if !i.IP.Packed() && i.Counters.Packed() { // Type IPTEntry doesn't have a packed layout in memory, fall back to MarshalBytes. buf := make([]byte, i.SizeBytes()) i.MarshalBytes(buf) @@ -1818,7 +1818,7 @@ func (i *IPTIP) UnmarshalBytes(src []byte) { // Packed implements marshal.Marshallable.Packed. //go:nosplit func (i *IPTIP) Packed() bool { - return i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() + return i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() } // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe. @@ -1844,7 +1844,7 @@ func (i *IPTIP) UnmarshalUnsafe(src []byte) { // CopyOutN implements marshal.Marshallable.CopyOutN. //go:nosplit func (i *IPTIP) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) { - if !i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() { + if !i.SrcMask.Packed() && i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() { // Type IPTIP doesn't have a packed layout in memory, fall back to MarshalBytes. buf := task.CopyScratchBuffer(i.SizeBytes()) // escapes: okay. i.MarshalBytes(buf) // escapes: fallback. @@ -1900,7 +1900,7 @@ func (i *IPTIP) CopyIn(task marshal.Task, addr usermem.Addr) (int, error) { // WriteTo implements io.WriterTo.WriteTo. func (i *IPTIP) WriteTo(w io.Writer) (int64, error) { - if !i.DstMask.Packed() && i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() { + if !i.Src.Packed() && i.Dst.Packed() && i.SrcMask.Packed() && i.DstMask.Packed() { // Type IPTIP doesn't have a packed layout in memory, fall back to MarshalBytes. buf := make([]byte, i.SizeBytes()) i.MarshalBytes(buf) diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go index 6ae796c6d..59323086d 100644 --- a/pkg/sentry/fsimpl/gofer/gofer.go +++ b/pkg/sentry/fsimpl/gofer/gofer.go @@ -192,10 +192,14 @@ const ( // // - File timestamps are based on client clocks. This ensures that users of // the client observe timestamps that are coherent with their own clocks - // and consistent with Linux's semantics. However, since it is not always - // possible for clients to set arbitrary atimes and mtimes, and never - // possible for clients to set arbitrary ctimes, file timestamp changes are - // stored in the client only and never sent to the remote filesystem. + // and consistent with Linux's semantics (in particular, it is not always + // possible for clients to set arbitrary atimes and mtimes depending on the + // remote filesystem implementation, and never possible for clients to set + // arbitrary ctimes.) If a dentry containing a client-defined atime or + // mtime is evicted from cache, client timestamps will be sent to the + // remote filesystem on a best-effort basis to attempt to ensure that + // timestamps will be preserved when another dentry representing the same + // file is instantiated. InteropModeExclusive InteropMode = iota // InteropModeWritethrough is appropriate when there are read-only users of @@ -621,6 +625,12 @@ type dentry struct { // File size, protected by both metadataMu and dataMu (i.e. both must be // locked to mutate it; locking either is sufficient to access it). size uint64 + // If this dentry does not represent a synthetic file, deleted is 0, and + // atimeDirty/mtimeDirty are non-zero, atime/mtime may have diverged from the + // remote file's timestamps, which should be updated when this dentry is + // evicted. + atimeDirty uint32 + mtimeDirty uint32 // nlink counts the number of hard links to this dentry. It's updated and // accessed using atomic operations. It's not protected by metadataMu like the @@ -801,10 +811,12 @@ func (d *dentry) updateFromP9AttrsLocked(mask p9.AttrMask, attr *p9.Attr) { if attr.BlockSize != 0 { atomic.StoreUint32(&d.blockSize, uint32(attr.BlockSize)) } - if mask.ATime { + // Don't override newer client-defined timestamps with old server-defined + // ones. + if mask.ATime && atomic.LoadUint32(&d.atimeDirty) == 0 { atomic.StoreInt64(&d.atime, dentryTimestampFromP9(attr.ATimeSeconds, attr.ATimeNanoSeconds)) } - if mask.MTime { + if mask.MTime && atomic.LoadUint32(&d.mtimeDirty) == 0 { atomic.StoreInt64(&d.mtime, dentryTimestampFromP9(attr.MTimeSeconds, attr.MTimeNanoSeconds)) } if mask.CTime { @@ -901,51 +913,44 @@ func (d *dentry) setStat(ctx context.Context, creds *auth.Credentials, opts *vfs return err } defer mnt.EndWrite() - setLocalAtime := false - setLocalMtime := false + + if stat.Mask&linux.STATX_SIZE != 0 { + // Reject attempts to truncate files other than regular files, since + // filesystem implementations may return the wrong errno. + switch mode.FileType() { + case linux.S_IFREG: + // ok + case linux.S_IFDIR: + return syserror.EISDIR + default: + return syserror.EINVAL + } + } + + var now int64 if d.cachedMetadataAuthoritative() { - // Timestamp updates will be handled locally. - setLocalAtime = stat.Mask&linux.STATX_ATIME != 0 - setLocalMtime = stat.Mask&linux.STATX_MTIME != 0 - stat.Mask &^= linux.STATX_ATIME | linux.STATX_MTIME - - // Prepare for truncate. - if stat.Mask&linux.STATX_SIZE != 0 { - switch mode.FileType() { - case linux.ModeRegular: - if !setLocalMtime { - // Truncate updates mtime. - setLocalMtime = true - stat.Mtime.Nsec = linux.UTIME_NOW - } - case linux.ModeDirectory: - return syserror.EISDIR - default: - return syserror.EINVAL + // Truncate updates mtime. + if stat.Mask&(linux.STATX_SIZE|linux.STATX_MTIME) == linux.STATX_SIZE { + stat.Mask |= linux.STATX_MTIME + stat.Mtime = linux.StatxTimestamp{ + Nsec: linux.UTIME_NOW, } } + + // Use client clocks for timestamps. + now = d.fs.clock.Now().Nanoseconds() + if stat.Mask&linux.STATX_ATIME != 0 && stat.Atime.Nsec == linux.UTIME_NOW { + stat.Atime = statxTimestampFromDentry(now) + } + if stat.Mask&linux.STATX_MTIME != 0 && stat.Mtime.Nsec == linux.UTIME_NOW { + stat.Mtime = statxTimestampFromDentry(now) + } } + d.metadataMu.Lock() defer d.metadataMu.Unlock() - if stat.Mask&linux.STATX_SIZE != 0 { - // The size needs to be changed even when - // !d.cachedMetadataAuthoritative() because d.mappings has to be - // updated. - d.updateFileSizeLocked(stat.Size) - } if !d.isSynthetic() { if stat.Mask != 0 { - if stat.Mask&linux.STATX_SIZE != 0 { - // Check whether to allow a truncate request to be made. - switch d.mode & linux.S_IFMT { - case linux.S_IFREG: - // Allow. - case linux.S_IFDIR: - return syserror.EISDIR - default: - return syserror.EINVAL - } - } if err := d.file.setAttr(ctx, p9.SetAttrMask{ Permissions: stat.Mask&linux.STATX_MODE != 0, UID: stat.Mask&linux.STATX_UID != 0, @@ -967,6 +972,11 @@ func (d *dentry) setStat(ctx context.Context, creds *auth.Credentials, opts *vfs }); err != nil { return err } + if stat.Mask&linux.STATX_SIZE != 0 { + // Privatized copy-on-write mappings of truncated pages need to + // be invalidated even if InteropModeShared is in effect. + d.updateFileSizeLocked(stat.Size) + } } if d.fs.opts.interop == InteropModeShared { // There's no point to updating d's metadata in this case since @@ -976,7 +986,6 @@ func (d *dentry) setStat(ctx context.Context, creds *auth.Credentials, opts *vfs return nil } } - now := d.fs.clock.Now().Nanoseconds() if stat.Mask&linux.STATX_MODE != 0 { atomic.StoreUint32(&d.mode, d.fileType()|uint32(stat.Mode)) } @@ -986,23 +995,18 @@ func (d *dentry) setStat(ctx context.Context, creds *auth.Credentials, opts *vfs if stat.Mask&linux.STATX_GID != 0 { atomic.StoreUint32(&d.gid, stat.GID) } - if setLocalAtime { - if stat.Atime.Nsec == linux.UTIME_NOW { - atomic.StoreInt64(&d.atime, now) - } else { - atomic.StoreInt64(&d.atime, dentryTimestampFromStatx(stat.Atime)) - } - // Restore mask bits that we cleared earlier. - stat.Mask |= linux.STATX_ATIME - } - if setLocalMtime { - if stat.Mtime.Nsec == linux.UTIME_NOW { - atomic.StoreInt64(&d.mtime, now) - } else { - atomic.StoreInt64(&d.mtime, dentryTimestampFromStatx(stat.Mtime)) - } - // Restore mask bits that we cleared earlier. - stat.Mask |= linux.STATX_MTIME + // Note that stat.Atime.Nsec and stat.Mtime.Nsec can't be UTIME_NOW because + // if d.cachedMetadataAuthoritative() then we converted stat.Atime and + // stat.Mtime to client-local timestamps above, and if + // !d.cachedMetadataAuthoritative() then we returned after calling + // d.file.setAttr(). For the same reason, now must have been initialized. + if stat.Mask&linux.STATX_ATIME != 0 { + atomic.StoreInt64(&d.atime, dentryTimestampFromStatx(stat.Atime)) + atomic.StoreUint32(&d.atimeDirty, 0) + } + if stat.Mask&linux.STATX_MTIME != 0 { + atomic.StoreInt64(&d.mtime, dentryTimestampFromStatx(stat.Mtime)) + atomic.StoreUint32(&d.mtimeDirty, 0) } atomic.StoreInt64(&d.ctime, now) return nil @@ -1248,7 +1252,7 @@ func (d *dentry) destroyLocked(ctx context.Context) { // Write dirty pages back to the remote filesystem. if d.handleWritable { if err := fsutil.SyncDirtyAll(ctx, &d.cache, &d.dirty, d.size, mf, d.handle.writeFromBlocksAt); err != nil { - log.Warningf("gofer.dentry.DecRef: failed to write dirty data back: %v", err) + log.Warningf("gofer.dentry.destroyLocked: failed to write dirty data back: %v", err) } } // Discard cached data. @@ -1261,6 +1265,28 @@ func (d *dentry) destroyLocked(ctx context.Context) { d.handleMu.Unlock() if !d.file.isNil() { + if !d.isDeleted() { + // Write dirty timestamps back to the remote filesystem. + atimeDirty := atomic.LoadUint32(&d.atimeDirty) != 0 + mtimeDirty := atomic.LoadUint32(&d.mtimeDirty) != 0 + if atimeDirty || mtimeDirty { + atime := atomic.LoadInt64(&d.atime) + mtime := atomic.LoadInt64(&d.mtime) + if err := d.file.setAttr(ctx, p9.SetAttrMask{ + ATime: atimeDirty, + ATimeNotSystemTime: atimeDirty, + MTime: mtimeDirty, + MTimeNotSystemTime: mtimeDirty, + }, p9.SetAttr{ + ATimeSeconds: uint64(atime / 1e9), + ATimeNanoSeconds: uint64(atime % 1e9), + MTimeSeconds: uint64(mtime / 1e9), + MTimeNanoSeconds: uint64(mtime % 1e9), + }); err != nil { + log.Warningf("gofer.dentry.destroyLocked: failed to write dirty timestamps back: %v", err) + } + } + } d.file.close(ctx) d.file = p9file{} // Remove d from the set of syncable dentries. diff --git a/pkg/sentry/fsimpl/gofer/time.go b/pkg/sentry/fsimpl/gofer/time.go index 0eef4e16e..2cb8191b9 100644 --- a/pkg/sentry/fsimpl/gofer/time.go +++ b/pkg/sentry/fsimpl/gofer/time.go @@ -47,6 +47,7 @@ func (d *dentry) touchAtime(mnt *vfs.Mount) { now := d.fs.clock.Now().Nanoseconds() d.metadataMu.Lock() atomic.StoreInt64(&d.atime, now) + atomic.StoreUint32(&d.atimeDirty, 1) d.metadataMu.Unlock() mnt.EndWrite() } @@ -67,6 +68,7 @@ func (d *dentry) touchCMtime() { d.metadataMu.Lock() atomic.StoreInt64(&d.mtime, now) atomic.StoreInt64(&d.ctime, now) + atomic.StoreUint32(&d.mtimeDirty, 1) d.metadataMu.Unlock() } @@ -76,4 +78,5 @@ func (d *dentry) touchCMtimeLocked() { now := d.fs.clock.Now().Nanoseconds() atomic.StoreInt64(&d.mtime, now) atomic.StoreInt64(&d.ctime, now) + atomic.StoreUint32(&d.mtimeDirty, 1) } |