diff options
Diffstat (limited to 'pkg/sentry/fsimpl/verity/verity.go')
| -rw-r--r-- | pkg/sentry/fsimpl/verity/verity.go | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/pkg/sentry/fsimpl/verity/verity.go b/pkg/sentry/fsimpl/verity/verity.go index ffc8f019d..2227b542a 100644 --- a/pkg/sentry/fsimpl/verity/verity.go +++ b/pkg/sentry/fsimpl/verity/verity.go @@ -39,6 +39,7 @@ import ( "encoding/json" "fmt" "math" + "sort" "strconv" "strings" "sync/atomic" @@ -509,6 +510,7 @@ func (fstype FilesystemType) GetFilesystem(ctx context.Context, vfsObj *vfs.Virt if err := fs.verifyStatAndChildrenLocked(ctx, d, stat); err != nil { return nil, nil, err } + d.generateChildrenList() } d.vfsd.Init(d) @@ -565,6 +567,11 @@ type dentry struct { // populated by enableVerity. childrenNames is also protected by dirMu. childrenNames map[string]struct{} + // childrenList is a complete sorted list of childrenNames. This list + // is generated when verity is enabled, or the first time the file is + // verified in non runtime enable mode. + childrenList []string + // lowerVD is the VirtualDentry in the underlying file system. It is // never modified after initialized. lowerVD vfs.VirtualDentry @@ -750,6 +757,17 @@ func (d *dentry) verityEnabled() bool { return !d.fs.allowRuntimeEnable || len(d.hash) != 0 } +// generateChildrenList generates a sorted childrenList from childrenNames, and +// cache it in d for hashing. +func (d *dentry) generateChildrenList() { + if len(d.childrenList) == 0 && len(d.childrenNames) != 0 { + for child := range d.childrenNames { + d.childrenList = append(d.childrenList, child) + } + sort.Strings(d.childrenList) + } +} + // getLowerAt returns the dentry in the underlying file system, which is // represented by filename relative to d. func (d *dentry) getLowerAt(ctx context.Context, vfsObj *vfs.VirtualFilesystem, filename string) (vfs.VirtualDentry, error) { @@ -963,10 +981,12 @@ func (fd *fileDescription) generateMerkleLocked(ctx context.Context) ([]byte, ui return nil, 0, err } + fd.d.generateChildrenList() + params := &merkletree.GenerateParams{ TreeReader: &merkleReader, TreeWriter: &merkleWriter, - Children: fd.d.childrenNames, + Children: fd.d.childrenList, HashAlgorithms: fd.d.fs.alg.toLinuxHashAlg(), Name: fd.d.name, Mode: uint32(stat.Mode), @@ -1262,7 +1282,7 @@ func (fd *fileDescription) PRead(ctx context.Context, dst usermem.IOSequence, of Mode: fd.d.mode, UID: fd.d.uid, GID: fd.d.gid, - Children: fd.d.childrenNames, + Children: fd.d.childrenList, HashAlgorithms: fd.d.fs.alg.toLinuxHashAlg(), ReadOffset: offset, ReadSize: dst.NumBytes(), |