Merge release-20210921.0-39-g65698b627 (automated)

2 files changed, 3 insertions, 39 deletions

diff --git a/pkg/safecopy/safecopy.go b/pkg/safecopy/safecopy.go
index a9711e63d..0dd0aea83 100644
--- a/pkg/safecopy/safecopy.go
+++ b/pkg/safecopy/safecopy.go
@@ -23,6 +23,7 @@ import (
 	"golang.org/x/sys/unix"
 	"gvisor.dev/gvisor/pkg/errors"
 	"gvisor.dev/gvisor/pkg/errors/linuxerr"
+	"gvisor.dev/gvisor/pkg/sighandling"
 )
 
 // SegvError is returned when a safecopy function receives SIGSEGV.
@@ -132,10 +133,10 @@ func initializeAddresses() {
 
 func init() {
 	initializeAddresses()
-	if err := ReplaceSignalHandler(unix.SIGSEGV, addrOfSignalHandler(), &savedSigSegVHandler); err != nil {
+	if err := sighandling.ReplaceSignalHandler(unix.SIGSEGV, addrOfSignalHandler(), &savedSigSegVHandler); err != nil {
 		panic(fmt.Sprintf("Unable to set handler for SIGSEGV: %v", err))
 	}
-	if err := ReplaceSignalHandler(unix.SIGBUS, addrOfSignalHandler(), &savedSigBusHandler); err != nil {
+	if err := sighandling.ReplaceSignalHandler(unix.SIGBUS, addrOfSignalHandler(), &savedSigBusHandler); err != nil {
 		panic(fmt.Sprintf("Unable to set handler for SIGBUS: %v", err))
 	}
 	linuxerr.AddErrorUnwrapper(func(e error) (*errors.Error, bool) {
diff --git a/pkg/safecopy/safecopy_unsafe.go b/pkg/safecopy/safecopy_unsafe.go
index 2365b2c0d..15f84abea 100644
--- a/pkg/safecopy/safecopy_unsafe.go
+++ b/pkg/safecopy/safecopy_unsafe.go
@@ -20,7 +20,6 @@ import (
 	"unsafe"
 
 	"golang.org/x/sys/unix"
-	"gvisor.dev/gvisor/pkg/abi/linux"
 )
 
 // maxRegisterSize is the maximum register size used in memcpy and memclr. It
@@ -332,39 +331,3 @@ func errorFromFaultSignal(addr uintptr, sig int32) error {
 		panic(fmt.Sprintf("safecopy got unexpected signal %d at address %#x", sig, addr))
 	}
 }
-
-// ReplaceSignalHandler replaces the existing signal handler for the provided
-// signal with the one that handles faults in safecopy-protected functions.
-//
-// It stores the value of the previously set handler in previous.
-//
-// This function will be called on initialization in order to install safecopy
-// handlers for appropriate signals. These handlers will call the previous
-// handler however, and if this is function is being used externally then the
-// same courtesy is expected.
-func ReplaceSignalHandler(sig unix.Signal, handler uintptr, previous *uintptr) error {
-	var sa linux.SigAction
-	const maskLen = 8
-
-	// Get the existing signal handler information, and save the current
-	// handler. Once we replace it, we will use this pointer to fall back to
-	// it when we receive other signals.
-	if _, _, e := unix.RawSyscall6(unix.SYS_RT_SIGACTION, uintptr(sig), 0, uintptr(unsafe.Pointer(&sa)), maskLen, 0, 0); e != 0 {
-		return e
-	}
-
-	// Fail if there isn't a previous handler.
-	if sa.Handler == 0 {
-		return fmt.Errorf("previous handler for signal %x isn't set", sig)
-	}
-
-	*previous = uintptr(sa.Handler)
-
-	// Install our own handler.
-	sa.Handler = uint64(handler)
-	if _, _, e := unix.RawSyscall6(unix.SYS_RT_SIGACTION, uintptr(sig), uintptr(unsafe.Pointer(&sa)), 0, maskLen, 0, 0); e != 0 {
-		return e
-	}
-
-	return nil
-}