AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAMBXAAAA///CSdIE")
panic: replaceArg: group fields don't match: 1/4

goroutine 24 [running]:
github.com/google/syzkaller/prog.replaceArg({0x9fabc8?, 0x401d9e2c60?}, {0x9fabc8?, 0x401d9e2e40?})
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/prog.go:377 +0x3fc
github.com/google/syzkaller/prog.replaceArg({0x9fabc8?, 0x401d9e2c40?}, {0x9fabc8?, 0x401d9e2e00?})
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/prog.go:382 +0x328
github.com/google/syzkaller/prog.replaceArg({0x9fabc8?, 0x401d9e2c20?}, {0x9fabc8?, 0x401d9e2de0?})
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/prog.go:382 +0x328
github.com/google/syzkaller/prog.replaceArg({0x9fabc8?, 0x401d9e2b00?}, {0x9fabc8?, 0x401d9e2dc0?})
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/prog.go:382 +0x328
github.com/google/syzkaller/prog.replaceArg({0x9fabc8?, 0x401d9e2ae0?}, {0x9fabc8?, 0x401d9e2da0?})
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/prog.go:382 +0x328
github.com/google/syzkaller/prog.(*StructType).mutate(0x1251ae0, 0x401d9e2d60, 0x401a4a8a50, {0x9fabc8, 0x401d9e2a00?}, {0x401a4a8a08, {0x1914440, 0x4, 0x4}, 0x401a090fc0, ...})
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/mutation.go:490 +0x170
github.com/google/syzkaller/prog.(*Target).mutateArg(0x40002b4000?, 0x401a091020?, 0x1024?, {0x9fabc8, 0x401d9e2a00}, {0x401a4a8a08, {0x1914440, 0x4, 0x4}, 0x401a090fc0, ...}, ...)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/mutation.go:245 +0xc0
github.com/google/syzkaller/prog.(*mutator).mutateArg(0x40196fbd48)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/mutation.go:196 +0x1f4
github.com/google/syzkaller/prog.(*Prog).Mutate(0x401cdf19c0, {0x9f6e48?, 0x401c9243f0}, 0x1e, 0x4018bd2140, 0x400007c930, {0x400ed80000, 0xf6f7, 0x11000})
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/mutation.go:51 +0x224
main.(*Proc).smashInput(0x4018bd2300, 0x401be30010)
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/proc.go:221 +0x10c
main.(*Proc).loop(0x4018bd2300)
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/proc.go:78 +0xf4
created by main.main in goroutine 1
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:336 +0x1288