diff options
Diffstat (limited to 'pkg/sentry/arch/stack_unsafe.go')
| -rw-r--r-- | pkg/sentry/arch/stack_unsafe.go | 23 |
1 files changed, 4 insertions, 19 deletions
diff --git a/pkg/sentry/arch/stack_unsafe.go b/pkg/sentry/arch/stack_unsafe.go index a90d297ee..0e478e434 100644 --- a/pkg/sentry/arch/stack_unsafe.go +++ b/pkg/sentry/arch/stack_unsafe.go @@ -15,8 +15,6 @@ package arch import ( - "reflect" - "runtime" "unsafe" "gvisor.dev/gvisor/pkg/marshal/primitive" @@ -33,35 +31,22 @@ import ( // On error, the contents of the stack and the bottom cursor are undefined. func (s *Stack) pushAddrSliceAndTerminator(src []usermem.Addr) (int, error) { // Note: Stack grows upwards, so push the terminator first. - srcHdr := (*reflect.SliceHeader)(unsafe.Pointer(&src)) switch s.Arch.Width() { case 8: nNull, err := primitive.CopyUint64Out(s, StackBottomMagic, 0) if err != nil { return 0, err } - var dst []uint64 - dstHdr := (*reflect.SliceHeader)(unsafe.Pointer(&dst)) - dstHdr.Data = srcHdr.Data - dstHdr.Len = srcHdr.Len - dstHdr.Cap = srcHdr.Cap - n, err := primitive.CopyUint64SliceOut(s, StackBottomMagic, dst) - // Ensures src doesn't get GCed until we're done using it through dst. - runtime.KeepAlive(src) + srcAsUint64 := *(*[]uint64)(unsafe.Pointer(&src)) + n, err := primitive.CopyUint64SliceOut(s, StackBottomMagic, srcAsUint64) return n + nNull, err case 4: nNull, err := primitive.CopyUint32Out(s, StackBottomMagic, 0) if err != nil { return 0, err } - var dst []uint32 - dstHdr := (*reflect.SliceHeader)(unsafe.Pointer(&dst)) - dstHdr.Data = srcHdr.Data - dstHdr.Len = srcHdr.Len - dstHdr.Cap = srcHdr.Cap - n, err := primitive.CopyUint32SliceOut(s, StackBottomMagic, dst) - // Ensure src doesn't get GCed until we're done using it through dst. - runtime.KeepAlive(src) + srcAsUint32 := *(*[]uint32)(unsafe.Pointer(&src)) + n, err := primitive.CopyUint32SliceOut(s, StackBottomMagic, srcAsUint32) return n + nNull, err default: panic("Unsupported arch width") |