panic: sandbox escaping file name "../file0", Files are map[../file0:true]

goroutine 16 [running]:
github.com/google/syzkaller/prog.(*randGen).filename(0xc0004acf80, 0xc0007b6040, 0xbf7940, 0xc0008c3d00, 0xc0008c3958)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:161 +0x2e3
github.com/google/syzkaller/prog.(*BufferType).generate(0xbf7940, 0xc0004acf80, 0xc0007b6040, 0xc000079500, 0x135b1b4a6d22b9cd, 0xc0008c39e8, 0x4f0c53, 0xc00068a330)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:646 +0x4fc
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc0004acf80, 0xc0007b6040, 0x8fd620, 0xbf7940, 0x300, 0x0, 0x0, 0x0, 0x0, 0x0)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:581 +0x1b6
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc0004acf80, 0xc0007b6040, 0x8fd620, 0xbf7940, 0xaaaaaaaaaaaaaaaa, 0x38, 0x7437e2, 0x87a299, 0x3)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:530 +0x52
github.com/google/syzkaller/prog.(*PtrType).generate(0xbd8920, 0xc0004acf80, 0xc0007b6040, 0x40b7ff, 0xc000553d70, 0x30, 0x30, 0x8115a0)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:729 +0x84
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc0004acf80, 0xc0007b6040, 0x8fda80, 0xbd8920, 0xc0008c3b00, 0x0, 0x0, 0x0, 0x0, 0x0)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:581 +0x1b6
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc0004acf80, 0xc0007b6040, 0x8fda80, 0xbd8920, 0x3, 0x3, 0x0, 0x203000, 0xc0008c3ce8)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:530 +0x52
github.com/google/syzkaller/prog.(*randGen).generateArgs(0xc0004acf80, 0xc0007b6040, 0xbcae20, 0x3, 0x3, 0xb0e3de0fb7cd2412, 0xc0008c3db0, 0x72beae, 0x7f3580, 0xc000743740, ...)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:518 +0x11d
github.com/google/syzkaller/prog.(*randGen).generateParticularCall(0xc0004acf80, 0xc0007b6040, 0xbe1da0, 0x16, 0xc0007b6040, 0xc00000d928)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:462 +0xd1
github.com/google/syzkaller/prog.(*randGen).generateCall(0xc0004acf80, 0xc0007b6040, 0xc000469fc0, 0xc0007b6040, 0xc0008c3e48, 0x731217)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:454 +0xa4
github.com/google/syzkaller/prog.(*mutator).insertCall(0xc0008c3ed0, 0x14)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/mutation.go:118 +0xcb
github.com/google/syzkaller/prog.(*Prog).Mutate(0xc000469fc0, 0x8f8680, 0xc00068a330, 0x1e, 0xc000664d80, 0xc0007a2000, 0xa29, 0xc00)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/mutation.go:32 +0x299
main.(*Proc).loop(0xc000664dc0)
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/proc.go:99 +0x446created by main.main
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:236 +0xfe2