panic: bad arg kind: <nil>

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 78d697fc Linux 4.14.172
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1417e681e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=31ad682bcda9b93f
dashboard link: https://syzkaller.appspot.com/bug?extid=ac3a8198efafab3631f3
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+ac3a81...@syzkaller.appspotmail.com

syz_mount_image$ext4(0x0, 0x0, 0x0, 0x1, &(0x7f00000007c0)=[{&(0x7f0000000580)="62f23e748cdfecc0d3bcb88248f9f8f8e87edc5637656d6e511dcdc6041c8d8a0957939950c15c7ac6360c7820e1d5957ba4167f17600b58767db91e29eb92a20f86dddfb0f8dda322d3", 0x4a, 0x1}], 0x100488, 0x0)
panic: bad arg kind: <nil>

goroutine 30 [running]:
github.com/google/syzkaller/prog.clone(0x0, 0x0, 0xc440b15b60, 0xc458962ea0, 0x3)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/clone.go:79 +0x9aa
github.com/google/syzkaller/prog.(*Prog).Clone(0xc4388578c0, 0x8b5cd2)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/clone.go:24 +0x19d
github.com/google/syzkaller/prog.resourceCentric(0xfc5540, 0xc42860b090, 0xc43f428340, 0x410801, 0x20, 0x85ec00, 0x13)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:848 +0xc1
github.com/google/syzkaller/prog.(*ResourceType).generate(0xfc5540, 0xc43f428340, 0xc42860b090, 0xc443d71f88, 0x4dfde3, 0xc4248af500, 0x6605ba7955aa43ec, 0xc443d71fa8)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:681 +0x931
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc43f428340, 0xc42860b090, 0xa45a00, 0xfc5540, 0x100, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:674 +0x1b8
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc43f428340, 0xc42860b090, 0xa45a00, 0xfc5540, 0x410848, 0xc443d720c0, 0x72f044, 0x8a5f29, 0x3)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:623 +0x52
github.com/google/syzkaller/prog.(*PtrType).generate(0xfc54e0, 0xc43f428340, 0xc42860b090, 0xa42160, 0xc43df1aba0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:829 +0xf7
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc43f428340, 0xc42860b090, 0xa45940, 0xfc54e0, 0xc443d72100, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:674 +0x1b8
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc43f428340, 0xc42860b090, 0xa45940, 0xfc54e0, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:623 +0x52
github.com/google/syzkaller/prog.(*randGen).generateArgs(0xc43f428340, 0xc42860b090, 0xe44ac0, 0x3, 0x3, 0xc435a7ad50, 0x57df77fd572b8ed2, 0xc443d72350, 0x4e00ff, 0xc435a7ad50, ...)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:611 +0x18b
github.com/google/syzkaller/prog.(*randGen).generateParticularCall(0xc43f428340, 0xc42860b090, 0x1c28680, 0x200, 0x201, 0xc43df20000)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:555 +0xd6
github.com/google/syzkaller/prog.(*randGen).createResource(0xc43f428340, 0xc42860b090, 0x1120a00, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:388 +0x52b
github.com/google/syzkaller/prog.(*ResourceType).generate(0x1120a00, 0xc43f428340, 0xc42860b090, 0x91, 0xc443d728a8, 0x41020d, 0xc438827b30, 0x30)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:710 +0x80b
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc43f428340, 0xc42860b090, 0xa45a00, 0x1120a00, 0xc443d72800, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:674 +0x1b8
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc43f428340, 0xc42860b090, 0xa45a00, 0x1120a00, 0x18, 0xc43df1ab60, 0x0, 0x1ec0780, 0x1ec0780)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:623 +0x52
github.com/google/syzkaller/prog.(*ArrayType).generate(0x13355c0, 0xc43f428340, 0xc42860b090, 0xa42160, 0xc43df1ab60, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:805 +0x16a
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc43f428340, 0xc42860b090, 0xa45340, 0x13355c0, 0xc443d72a00, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:674 +0x1b8
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc43f428340, 0xc42860b090, 0xa45340, 0x13355c0, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:623 +0x52
github.com/google/syzkaller/prog.(*randGen).generateArgs(0xc43f428340, 0xc42860b090, 0xf8fd40, 0x4, 0x4, 0xc443d72c90, 0xbc4619b0, 0xf4e5ab858a84ab6e, 0xc443d72c70, 0xf40000000072e348, ...)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:611 +0x18b
github.com/google/syzkaller/prog.(*StructType).generate(0xf43880, 0xc43f428340, 0xc42860b090, 0x34, 0x1ede6a0, 0x41020d, 0xc43255a2b0, 0x10)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:813 +0x74
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc43f428340, 0xc42860b090, 0xa45ac0, 0xf43880, 0xc443d72d00, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:674 +0x1b8
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc43f428340, 0xc42860b090, 0xa45ac0, 0xf43880, 0x1, 0x1, 0x8, 0x93, 0xc443d72e60)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:623 +0x52
github.com/google/syzkaller/prog.(*randGen).generateArgs(0xc43f428340, 0xc42860b090, 0xd262d0, 0x1, 0x1, 0xc443d72f48, 0xbc4619b0, 0xdb1c1b4194daf347, 0xc443d72f28, 0xdb0000000072e348, ...)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:611 +0x18b
github.com/google/syzkaller/prog.(*StructType).generate(0xf43980, 0xc43f428340, 0xc42860b090, 0x2c, 0x1ede6a0, 0x41020d, 0xc43df1ab00, 0x20)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:813 +0x74
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc43f428340, 0xc42860b090, 0xa45ac0, 0xf43980, 0xc400000000, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:674 +0x1b8
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc43f428340, 0xc42860b090, 0xa45ac0, 0xf43980, 0xf3e843055136367c, 0xc443d730a8, 0xf30000000072ec28, 0x8b5eda, 0xa)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:623 +0x52
github.com/google/syzkaller/prog.(*UnionType).generate(0xde3d40, 0xc43f428340, 0xc42860b090, 0xa, 0x1ede6a0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:820 +0xa1
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc43f428340, 0xc42860b090, 0xa45b80, 0xde3d40, 0xc443d73100, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:674 +0x1b8
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc43f428340, 0xc42860b090, 0xa45b80, 0xde3d40, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:623 +0x52
github.com/google/syzkaller/prog.(*ArrayType).generate(0x12d28c0, 0xc43f428340, 0xc42860b090, 0xc443d732d0, 0x4dfde3, 0xc4248af500, 0x20294d10d4d22729, 0xc443d732f0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:805 +0x16a
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc43f428340, 0xc42860b090, 0xa45340, 0x12d28c0, 0x200, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:674 +0x1b8
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc43f428340, 0xc42860b090, 0xa45340, 0x12d28c0, 0x9ac9703582c90ddb, 0xc443d73408, 0x72f044, 0x8a5f29, 0x3)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:623 +0x52
github.com/google/syzkaller/prog.(*PtrType).generate(0xfaa300, 0xc43f428340, 0xc42860b090, 0x5, 0xc4275ce7d8, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:829 +0xf7
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc43f428340, 0xc42860b090, 0xa45940, 0xfaa300, 0xc443d73500, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:674 +0x1b8
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc43f428340, 0xc42860b090, 0xa45940, 0xfaa300, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:623 +0x52
github.com/google/syzkaller/prog.(*randGen).generateArgs(0xc43f428340, 0xc42860b090, 0x1c22c80, 0x9, 0x9, 0xc443d736e0, 0xbc4619b0, 0xed9128f7b8d46d36, 0xc443d736c0, 0xed0000000072e348, ...)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:611 +0x18b
github.com/google/syzkaller/prog.(*StructType).generate(0xe71b80, 0xc43f428340, 0xc42860b090, 0x9, 0x1ede6a0, 0x160, 0x160, 0xc43da99760)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:813 +0x74
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc43f428340, 0xc42860b090, 0xa45ac0, 0xe71b80, 0xc4539bf700, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:674 +0x1b8
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc43f428340, 0xc42860b090, 0xa45ac0, 0xe71b80, 0xc432afcf00, 0xb, 0xc, 0xb, 0xc)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:623 +0x52
github.com/google/syzkaller/prog.(*ArrayType).generate(0x12ff3e0, 0xc43f428340, 0xc42860b090, 0xc4539bf8e8, 0x4dfde3, 0xc4248af500, 0x17a1b0fc3f6efadf, 0xc4539bf908)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:805 +0x16a
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc43f428340, 0xc42860b090, 0xa45340, 0x12ff3e0, 0x200, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:674 +0x1b8
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc43f428340, 0xc42860b090, 0xa45340, 0x12ff3e0, 0xc4539bfa00, 0xc4539bfa20, 0x72f044, 0x8a5f29, 0x3)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:623 +0x52
github.com/google/syzkaller/prog.(*PtrType).generate(0x102bcc0, 0xc43f428340, 0xc42860b090, 0xa42260, 0xc43f42a100, 0x8, 0x8, 0xc431b4be08)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:829 +0xf7
github.com/google/syzkaller/prog.(*randGen).generateArgImpl(0xc43f428340, 0xc42860b090, 0xa45940, 0x102bcc0, 0xc4539bfb00, 0x0, 0x0, 0x0, 0x0, 0x0)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:674 +0x1b8
github.com/google/syzkaller/prog.(*randGen).generateArg(0xc43f428340, 0xc42860b090, 0xa45940, 0x102bcc0, 0xc431b4bdf0, 0x1, 0x1, 0x1, 0x1)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:623 +0x52
github.com/google/syzkaller/prog.(*randGen).generateArgs(0xc43f428340, 0xc42860b090, 0xf72300, 0x4, 0x4, 0x3b5ff1fcf5e04d05, 0xc4539bfcd8, 0x71450e, 0x81f0c0, 0xc439940000, ...)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:611 +0x18b
github.com/google/syzkaller/prog.(*randGen).generateParticularCall(0xc43f428340, 0xc42860b090, 0x1c7e1c0, 0x8d9, 0xc42860b090, 0xc429b82540)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:555 +0xd6
github.com/google/syzkaller/prog.(*randGen).generateCall(0xc43f428340, 0xc42860b090, 0xc429b81980, 0x9, 0xc429b81980, 0x0, 0xc42860b090)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/rand.go:547 +0xb4
github.com/google/syzkaller/prog.(*mutator).insertCall(0xc4539bfe08, 0x14)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/mutation.go:137 +0xf5
github.com/google/syzkaller/prog.(*Prog).Mutate(0xc429b81980, 0xa3fc20, 0xc441702b40, 0x1e, 0xc4416fa180, 0xc441724000, 0xc4fb, 0xf000)
/syzkaller/gopath/src/github.com/google/syzkaller/prog/mutation.go:42 +0x2a9
main.(*Proc).smashInput(0xc4416fab40, 0xc43c1daed0)
/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/proc.go:217 +0x131
main.(*Proc).loop(0xc4416fab40)
/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/proc.go:82 +0x194
created by main.main
/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:259 +0x1071


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.