diff options
| -rw-r--r-- | pkg/sentry/fsimpl/gofer/special_file.go | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/pkg/sentry/fsimpl/gofer/special_file.go b/pkg/sentry/fsimpl/gofer/special_file.go index dc960e5bf..576c57491 100644 --- a/pkg/sentry/fsimpl/gofer/special_file.go +++ b/pkg/sentry/fsimpl/gofer/special_file.go @@ -246,11 +246,12 @@ func (fd *specialFileFD) pwrite(ctx context.Context, src usermem.IOSequence, off d.touchCMtime() } buf := make([]byte, src.NumBytes()) - // Don't do partial writes if we get a partial read from src. - if _, err := src.CopyIn(ctx, buf); err != nil { - return 0, offset, err + copied, copyErr := src.CopyIn(ctx, buf) + if copied == 0 && copyErr != nil { + // Only return the error if we didn't get any data. + return 0, offset, copyErr } - n, err := fd.handle.writeFromBlocksAt(ctx, safemem.BlockSeqOf(safemem.BlockFromSafeSlice(buf)), uint64(offset)) + n, err := fd.handle.writeFromBlocksAt(ctx, safemem.BlockSeqOf(safemem.BlockFromSafeSlice(buf[:copied])), uint64(offset)) if err == syserror.EAGAIN { err = syserror.ErrWouldBlock } @@ -267,7 +268,10 @@ func (fd *specialFileFD) pwrite(ctx context.Context, src usermem.IOSequence, off atomic.StoreUint64(&d.size, uint64(offset)) } } - return int64(n), offset, err + if err != nil { + return int64(n), offset, err + } + return int64(n), offset, copyErr } // Write implements vfs.FileDescriptionImpl.Write. |