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-rw-r--r--pkg/sentry/fsimpl/gofer/gofer.go4
-rw-r--r--pkg/sentry/fsimpl/gofer/regular_file.go9
-rw-r--r--pkg/sentry/fsimpl/proc/task.go12
-rw-r--r--pkg/sentry/fsimpl/proc/task_files.go43
-rw-r--r--pkg/sentry/fsimpl/proc/tasks_test.go32
5 files changed, 77 insertions, 23 deletions
diff --git a/pkg/sentry/fsimpl/gofer/gofer.go b/pkg/sentry/fsimpl/gofer/gofer.go
index d00850e25..c4a8f0b38 100644
--- a/pkg/sentry/fsimpl/gofer/gofer.go
+++ b/pkg/sentry/fsimpl/gofer/gofer.go
@@ -1045,13 +1045,13 @@ func (d *dentry) ensureSharedHandle(ctx context.Context, read, write, trunc bool
// using the old file descriptor, preventing us from safely
// closing it. We could handle this by invalidating existing
// memmap.Translations, but this is expensive. Instead, use
- // dup2() to make the old file descriptor refer to the new file
+ // dup3 to make the old file descriptor refer to the new file
// description, then close the new file descriptor (which is no
// longer needed). Racing callers may use the old or new file
// description, but this doesn't matter since they refer to the
// same file (unless d.fs.opts.overlayfsStaleRead is true,
// which we handle separately).
- if err := syscall.Dup2(int(h.fd), int(d.handle.fd)); err != nil {
+ if err := syscall.Dup3(int(h.fd), int(d.handle.fd), 0); err != nil {
d.handleMu.Unlock()
ctx.Warningf("gofer.dentry.ensureSharedHandle: failed to dup fd %d to fd %d: %v", h.fd, d.handle.fd, err)
h.close(ctx)
diff --git a/pkg/sentry/fsimpl/gofer/regular_file.go b/pkg/sentry/fsimpl/gofer/regular_file.go
index 54c1031a7..e95209661 100644
--- a/pkg/sentry/fsimpl/gofer/regular_file.go
+++ b/pkg/sentry/fsimpl/gofer/regular_file.go
@@ -361,8 +361,15 @@ func (rw *dentryReadWriter) WriteFromBlocks(srcs safemem.BlockSeq) (uint64, erro
rw.d.handleMu.RLock()
if (rw.d.handle.fd >= 0 && !rw.d.fs.opts.forcePageCache) || rw.d.fs.opts.interop == InteropModeShared || rw.direct {
n, err := rw.d.handle.writeFromBlocksAt(rw.ctx, srcs, rw.off)
- rw.d.handleMu.RUnlock()
rw.off += n
+ rw.d.dataMu.Lock()
+ if rw.off > rw.d.size {
+ atomic.StoreUint64(&rw.d.size, rw.off)
+ // The remote file's size will implicitly be extended to the correct
+ // value when we write back to it.
+ }
+ rw.d.dataMu.Unlock()
+ rw.d.handleMu.RUnlock()
return n, err
}
diff --git a/pkg/sentry/fsimpl/proc/task.go b/pkg/sentry/fsimpl/proc/task.go
index 2d814668a..18e5cd6f6 100644
--- a/pkg/sentry/fsimpl/proc/task.go
+++ b/pkg/sentry/fsimpl/proc/task.go
@@ -62,11 +62,13 @@ func newTaskInode(inoGen InoGenerator, task *kernel.Task, pidns *kernel.PIDNames
"pid": newNamespaceSymlink(task, inoGen.NextIno(), "pid"),
"user": newNamespaceSymlink(task, inoGen.NextIno(), "user"),
}),
- "smaps": newTaskOwnedFile(task, inoGen.NextIno(), 0444, &smapsData{task: task}),
- "stat": newTaskOwnedFile(task, inoGen.NextIno(), 0444, &taskStatData{task: task, pidns: pidns, tgstats: isThreadGroup}),
- "statm": newTaskOwnedFile(task, inoGen.NextIno(), 0444, &statmData{task: task}),
- "status": newTaskOwnedFile(task, inoGen.NextIno(), 0444, &statusData{task: task, pidns: pidns}),
- "uid_map": newTaskOwnedFile(task, inoGen.NextIno(), 0644, &idMapData{task: task, gids: false}),
+ "oom_score": newTaskOwnedFile(task, inoGen.NextIno(), 0444, newStaticFile("0\n")),
+ "oom_score_adj": newTaskOwnedFile(task, inoGen.NextIno(), 0644, &oomScoreAdj{task: task}),
+ "smaps": newTaskOwnedFile(task, inoGen.NextIno(), 0444, &smapsData{task: task}),
+ "stat": newTaskOwnedFile(task, inoGen.NextIno(), 0444, &taskStatData{task: task, pidns: pidns, tgstats: isThreadGroup}),
+ "statm": newTaskOwnedFile(task, inoGen.NextIno(), 0444, &statmData{task: task}),
+ "status": newTaskOwnedFile(task, inoGen.NextIno(), 0444, &statusData{task: task, pidns: pidns}),
+ "uid_map": newTaskOwnedFile(task, inoGen.NextIno(), 0644, &idMapData{task: task, gids: false}),
}
if isThreadGroup {
contents["task"] = newSubtasks(task, pidns, inoGen, cgroupControllers)
diff --git a/pkg/sentry/fsimpl/proc/task_files.go b/pkg/sentry/fsimpl/proc/task_files.go
index efd3b3453..5a231ac86 100644
--- a/pkg/sentry/fsimpl/proc/task_files.go
+++ b/pkg/sentry/fsimpl/proc/task_files.go
@@ -525,3 +525,46 @@ func (i *ioData) Generate(ctx context.Context, buf *bytes.Buffer) error {
fmt.Fprintf(buf, "cancelled_write_bytes: %d\n", io.BytesWriteCancelled)
return nil
}
+
+// oomScoreAdj is a stub of the /proc/<pid>/oom_score_adj file.
+//
+// +stateify savable
+type oomScoreAdj struct {
+ kernfs.DynamicBytesFile
+
+ task *kernel.Task
+}
+
+var _ vfs.WritableDynamicBytesSource = (*oomScoreAdj)(nil)
+
+// Generate implements vfs.DynamicBytesSource.Generate.
+func (o *oomScoreAdj) Generate(ctx context.Context, buf *bytes.Buffer) error {
+ adj, err := o.task.OOMScoreAdj()
+ if err != nil {
+ return err
+ }
+ fmt.Fprintf(buf, "%d\n", adj)
+ return nil
+}
+
+// Write implements vfs.WritableDynamicBytesSource.Write.
+func (o *oomScoreAdj) Write(ctx context.Context, src usermem.IOSequence, offset int64) (int64, error) {
+ if src.NumBytes() == 0 {
+ return 0, nil
+ }
+
+ // Limit input size so as not to impact performance if input size is large.
+ src = src.TakeFirst(usermem.PageSize - 1)
+
+ var v int32
+ n, err := usermem.CopyInt32StringInVec(ctx, src.IO, src.Addrs, &v, src.Opts)
+ if err != nil {
+ return 0, err
+ }
+
+ if err := o.task.SetOOMScoreAdj(v); err != nil {
+ return 0, err
+ }
+
+ return n, nil
+}
diff --git a/pkg/sentry/fsimpl/proc/tasks_test.go b/pkg/sentry/fsimpl/proc/tasks_test.go
index c5d531fe0..0eb401619 100644
--- a/pkg/sentry/fsimpl/proc/tasks_test.go
+++ b/pkg/sentry/fsimpl/proc/tasks_test.go
@@ -63,21 +63,23 @@ var (
"thread-self": threadSelfLink.NextOff,
}
taskStaticFiles = map[string]testutil.DirentType{
- "auxv": linux.DT_REG,
- "cgroup": linux.DT_REG,
- "cmdline": linux.DT_REG,
- "comm": linux.DT_REG,
- "environ": linux.DT_REG,
- "gid_map": linux.DT_REG,
- "io": linux.DT_REG,
- "maps": linux.DT_REG,
- "ns": linux.DT_DIR,
- "smaps": linux.DT_REG,
- "stat": linux.DT_REG,
- "statm": linux.DT_REG,
- "status": linux.DT_REG,
- "task": linux.DT_DIR,
- "uid_map": linux.DT_REG,
+ "auxv": linux.DT_REG,
+ "cgroup": linux.DT_REG,
+ "cmdline": linux.DT_REG,
+ "comm": linux.DT_REG,
+ "environ": linux.DT_REG,
+ "gid_map": linux.DT_REG,
+ "io": linux.DT_REG,
+ "maps": linux.DT_REG,
+ "ns": linux.DT_DIR,
+ "oom_score": linux.DT_REG,
+ "oom_score_adj": linux.DT_REG,
+ "smaps": linux.DT_REG,
+ "stat": linux.DT_REG,
+ "statm": linux.DT_REG,
+ "status": linux.DT_REG,
+ "task": linux.DT_DIR,
+ "uid_map": linux.DT_REG,
}
)