prog: add stronger fallback signal

Also mixin resource constructors and some signature
of flags values for successful calls into fallback coverage.

2 files changed, 8 insertions, 15 deletions

diff --git a/pkg/ipc/ipc.go b/pkg/ipc/ipc.go
index 5ab5e26a7..65e883acf 100644
--- a/pkg/ipc/ipc.go
+++ b/pkg/ipc/ipc.go
@@ -19,7 +19,6 @@ import (
 	"unsafe"
 
 	"github.com/google/syzkaller/pkg/osutil"
-	"github.com/google/syzkaller/pkg/signal"
 	"github.com/google/syzkaller/prog"
 	"github.com/google/syzkaller/sys/targets"
 )
@@ -329,12 +328,14 @@ func (env *Env) Exec(opts *ExecOpts, p *prog.Prog) (output []byte, info []CallIn
 // We use syscall number or-ed with returned errno value as signal.
 // At least this gives us all combinations of syscall+errno.
 func addFallbackSignal(p *prog.Prog, info []CallInfo) {
-	for i, call := range p.Calls {
-		inf := &info[i]
-		if !inf.Executed || len(inf.Signal) != 0 {
-			continue
-		}
-		inf.Signal = []uint32{signal.EncodeFallback(call.Meta.ID, inf.Errno)}
+	callInfos := make([]prog.CallInfo, len(info))
+	for i, inf := range info {
+		callInfos[i].Executed = inf.Executed
+		callInfos[i].Errno = inf.Errno
+	}
+	p.FallbackSignal(callInfos)
+	for i, inf := range callInfos {
+		info[i].Signal = inf.Signal
 	}
 }
 
diff --git a/pkg/signal/signal.go b/pkg/signal/signal.go
index 9af1bcce1..20deba46a 100644
--- a/pkg/signal/signal.go
+++ b/pkg/signal/signal.go
@@ -191,11 +191,3 @@ func Minimize(corpus []Context) []interface{} {
 	}
 	return result
 }
-
-func EncodeFallback(id, errno int) uint32 {
-	return uint32(id)<<16 | uint32(errno)&0x3ff
-}
-
-func DecodeFallback(s uint32) (int, int) {
-	return int(s >> 16), int(s & 0x3ff)
-}