panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x28 pc=0xa00d4a]

goroutine 15 [running]:
main.diffProgInfo(0x0, 0x7f90494d6838?)
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:432 +0x2a
main.(*FuzzerTool).diffMaxSignal(0xb303a0?, 0xc0000dc801?)
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:442 +0x97
main.(*FuzzerTool).convertExecutionResult(0x0?, {{0x1e82, {0xc000c28000, 0x14b9c, 0x14b9c}, 0x0, 0x0, 0x0, 0x1, 0x0}, ...})
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:386 +0x46
main.(*FuzzerTool).exchangeDataCall(0xc00051e0f0, 0x1, {0xc001851f78, 0x1, 0xae8300?})
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:345 +0x325
main.(*FuzzerTool).exchangeDataWorker(0xc00051e0f0)
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:380 +0x79
created by main.main in goroutine 1
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:272 +0x143c
I0325 22:35:15.436820   15284 main.go:226] Exiting with status: 512