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Diffstat (limited to 'pkg/sentry/mm/metadata.go')
-rw-r--r-- | pkg/sentry/mm/metadata.go | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/pkg/sentry/mm/metadata.go b/pkg/sentry/mm/metadata.go new file mode 100644 index 000000000..32d5e2ff6 --- /dev/null +++ b/pkg/sentry/mm/metadata.go @@ -0,0 +1,139 @@ +// Copyright 2018 Google Inc. +// +// 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. + +package mm + +import ( + "gvisor.googlesource.com/gvisor/pkg/sentry/arch" + "gvisor.googlesource.com/gvisor/pkg/sentry/fs" + "gvisor.googlesource.com/gvisor/pkg/sentry/usermem" +) + +// ArgvStart returns the start of the application argument vector. +// +// There is no guarantee that this value is sensible w.r.t. ArgvEnd. +func (mm *MemoryManager) ArgvStart() usermem.Addr { + mm.metadataMu.Lock() + defer mm.metadataMu.Unlock() + return mm.argv.Start +} + +// SetArgvStart sets the start of the application argument vector. +func (mm *MemoryManager) SetArgvStart(a usermem.Addr) { + mm.metadataMu.Lock() + defer mm.metadataMu.Unlock() + mm.argv.Start = a +} + +// ArgvEnd returns the end of the application argument vector. +// +// There is no guarantee that this value is sensible w.r.t. ArgvStart. +func (mm *MemoryManager) ArgvEnd() usermem.Addr { + mm.metadataMu.Lock() + defer mm.metadataMu.Unlock() + return mm.argv.End +} + +// SetArgvEnd sets the end of the application argument vector. +func (mm *MemoryManager) SetArgvEnd(a usermem.Addr) { + mm.metadataMu.Lock() + defer mm.metadataMu.Unlock() + mm.argv.End = a +} + +// EnvvStart returns the start of the application environment vector. +// +// There is no guarantee that this value is sensible w.r.t. EnvvEnd. +func (mm *MemoryManager) EnvvStart() usermem.Addr { + mm.metadataMu.Lock() + defer mm.metadataMu.Unlock() + return mm.envv.Start +} + +// SetEnvvStart sets the start of the application environment vector. +func (mm *MemoryManager) SetEnvvStart(a usermem.Addr) { + mm.metadataMu.Lock() + defer mm.metadataMu.Unlock() + mm.envv.Start = a +} + +// EnvvEnd returns the end of the application environment vector. +// +// There is no guarantee that this value is sensible w.r.t. EnvvStart. +func (mm *MemoryManager) EnvvEnd() usermem.Addr { + mm.metadataMu.Lock() + defer mm.metadataMu.Unlock() + return mm.envv.End +} + +// SetEnvvEnd sets the end of the application environment vector. +func (mm *MemoryManager) SetEnvvEnd(a usermem.Addr) { + mm.metadataMu.Lock() + defer mm.metadataMu.Unlock() + mm.envv.End = a +} + +// Auxv returns the current map of auxiliary vectors. +func (mm *MemoryManager) Auxv() arch.Auxv { + mm.metadataMu.Lock() + defer mm.metadataMu.Unlock() + return append(arch.Auxv(nil), mm.auxv...) +} + +// SetAuxv sets the entire map of auxiliary vectors. +func (mm *MemoryManager) SetAuxv(auxv arch.Auxv) { + mm.metadataMu.Lock() + defer mm.metadataMu.Unlock() + mm.auxv = append(arch.Auxv(nil), auxv...) +} + +// Executable returns the executable, if available. +// +// An additional reference will be taken in the case of a non-nil executable, +// which must be released by the caller. +func (mm *MemoryManager) Executable() *fs.Dirent { + mm.metadataMu.Lock() + defer mm.metadataMu.Unlock() + + if mm.executable == nil { + return nil + } + + mm.executable.IncRef() + return mm.executable +} + +// SetExecutable sets the executable. +// +// This takes a reference on d. +func (mm *MemoryManager) SetExecutable(d *fs.Dirent) { + mm.metadataMu.Lock() + + // Grab a new reference. + d.IncRef() + + // Set the executable. + orig := mm.executable + mm.executable = d + + mm.metadataMu.Unlock() + + // Release the old reference. + // + // Do this without holding the lock, since it may wind up doing some + // I/O to sync the dirent, etc. + if orig != nil { + orig.DecRef() + } +} |