sys/test: add more tests

Add syz_errno syscall which sets errno to the argument,
and add a test with different errno values.
This mostly tests the testing infrastructure itself.

Add syz_compare syscall which compare two blobs,
this can be used for testing of argument memory layout.

Implement syz_mmap and fix Makefile to allow building syz-execprog for test OS.
Useful for debugging.

Update #603

14 files changed, 237 insertions, 15 deletions

diff --git a/Makefile b/Makefile
index f23eb3214..77647df52 100644
--- a/Makefile
+++ b/Makefile
@@ -68,6 +68,11 @@ ifneq ("$(GOTAGS)", "")
 endif
 GOTARGETFLAGS += "-tags=syz_target syz_os_$(TARGETOS) syz_arch_$(TARGETVMARCH) $(GOTAGS)"
 
+ifeq ("$(TARGETOS)", "test")
+	TARGETGOOS := $(HOSTOS)
+	TARGETGOARCH := $(HOSTARCH)
+endif
+
 ifeq ("$(TARGETOS)", "akaros")
 	TARGETGOOS := $(HOSTOS)
 	TARGETGOARCH := $(HOSTARCH)
diff --git a/executor/common_test.h b/executor/common_test.h
index 78b3f8e22..75ec81721 100644
--- a/executor/common_test.h
+++ b/executor/common_test.h
@@ -7,8 +7,43 @@
 #include <unistd.h>
 
 #if SYZ_EXECUTOR || __NR_syz_mmap
+#include <sys/mman.h>
+
+// syz_mmap(addr vma, len len[addr])
 static long syz_mmap(long a0, long a1)
 {
+	return (long)mmap((void*)a0, a1, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE | MAP_FIXED, -1, 0);
+}
+#endif
+
+#if SYZ_EXECUTOR || __NR_syz_errno
+#include <errno.h>
+
+// syz_errno(v int32)
+static long syz_errno(long v)
+{
+	errno = v;
+	return v == 0 ? 0 : -1;
+}
+#endif
+
+#if SYZ_EXECUTOR || __NR_syz_compare
+#include <errno.h>
+#include <string.h>
+
+// syz_compare(want ptr[in, string], want_len len[want], got ptr[in, compare_data], got_len len[got])
+static long syz_compare(long want, long want_len, long got, long got_len)
+{
+	if (want_len != got_len) {
+		debug("syz_compare: want_len=%lu got_len=%lu\n", want_len, got_len);
+		errno = EBADF;
+		return -1;
+	}
+	if (memcmp((void*)want, (void*)got, want_len)) {
+		debug("syz_compare: data differs\n");
+		errno = EINVAL;
+		return -1;
+	}
 	return 0;
 }
 #endif
diff --git a/executor/defs.h b/executor/defs.h
index bd92a80b2..eb73e512d 100644
--- a/executor/defs.h
+++ b/executor/defs.h
@@ -130,7 +130,7 @@
 
 #if GOARCH_32_fork_shmem
 #define GOARCH "32_fork_shmem"
-#define SYZ_REVISION "18f983f4760ca5ac41eaf7c18bd9f487f6dde42b"
+#define SYZ_REVISION "d09983a8bb4f2ccd0e303191862d170b5b636bd8"
 #define SYZ_EXECUTOR_USES_FORK_SERVER 1
 #define SYZ_EXECUTOR_USES_SHMEM 1
 #define SYZ_PAGE_SIZE 4096
@@ -140,7 +140,7 @@
 
 #if GOARCH_32_shmem
 #define GOARCH "32_shmem"
-#define SYZ_REVISION "9d4e8ff9d9c38d5fe7cdc046adcde8be29782e6b"
+#define SYZ_REVISION "8d0f255b4d310c70d0e7d65ac8e5c6c3032a9e14"
 #define SYZ_EXECUTOR_USES_FORK_SERVER 0
 #define SYZ_EXECUTOR_USES_SHMEM 1
 #define SYZ_PAGE_SIZE 8192
@@ -150,7 +150,7 @@
 
 #if GOARCH_64
 #define GOARCH "64"
-#define SYZ_REVISION "981444b6842c8896801fdf67dc75c454cad9e594"
+#define SYZ_REVISION "285bb68296c57fc93062731e5c0ecfbfc105d685"
 #define SYZ_EXECUTOR_USES_FORK_SERVER 0
 #define SYZ_EXECUTOR_USES_SHMEM 0
 #define SYZ_PAGE_SIZE 4096
@@ -160,7 +160,7 @@
 
 #if GOARCH_64_fork
 #define GOARCH "64_fork"
-#define SYZ_REVISION "1c9fe1f1a1f6f871fc5c088ca80174655322aca4"
+#define SYZ_REVISION "39c2288dd1c825ce7a587f946cfc91e0e453cf5e"
 #define SYZ_EXECUTOR_USES_FORK_SERVER 1
 #define SYZ_EXECUTOR_USES_SHMEM 0
 #define SYZ_PAGE_SIZE 8192
diff --git a/executor/syscalls.h b/executor/syscalls.h
index a8845adb5..6f53b4490 100644
--- a/executor/syscalls.h
+++ b/executor/syscalls.h
@@ -11439,6 +11439,8 @@ const call_t syscalls[] = {
 
 #if GOARCH_32_fork_shmem
 const call_t syscalls[] = {
+    {"syz_compare", 0, (syscall_t)syz_compare},
+    {"syz_errno", 0, (syscall_t)syz_errno},
     {"syz_mmap", 0, (syscall_t)syz_mmap},
 
 };
@@ -11446,6 +11448,8 @@ const call_t syscalls[] = {
 
 #if GOARCH_32_shmem
 const call_t syscalls[] = {
+    {"syz_compare", 0, (syscall_t)syz_compare},
+    {"syz_errno", 0, (syscall_t)syz_errno},
     {"syz_mmap", 0, (syscall_t)syz_mmap},
 
 };
@@ -11472,6 +11476,8 @@ const call_t syscalls[] = {
     {"mutate8", 0},
     {"serialize0", 0},
     {"serialize1", 0},
+    {"syz_compare", 0, (syscall_t)syz_compare},
+    {"syz_errno", 0, (syscall_t)syz_errno},
     {"syz_mmap", 0, (syscall_t)syz_mmap},
     {"test", 0},
     {"test$align0", 0},
@@ -11566,6 +11572,8 @@ const call_t syscalls[] = {
 
 #if GOARCH_64_fork
 const call_t syscalls[] = {
+    {"syz_compare", 0, (syscall_t)syz_compare},
+    {"syz_errno", 0, (syscall_t)syz_errno},
     {"syz_mmap", 0, (syscall_t)syz_mmap},
 
 };
diff --git a/pkg/csource/generated.go b/pkg/csource/generated.go
index 0bfedab3e..b4ffc279e 100644
--- a/pkg/csource/generated.go
+++ b/pkg/csource/generated.go
@@ -3409,8 +3409,37 @@ static void reset_test()
 #include <unistd.h>
 
 #if SYZ_EXECUTOR || __NR_syz_mmap
+#include <sys/mman.h>
 static long syz_mmap(long a0, long a1)
 {
+	return (long)mmap((void*)a0, a1, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE | MAP_FIXED, -1, 0);
+}
+#endif
+
+#if SYZ_EXECUTOR || __NR_syz_errno
+#include <errno.h>
+static long syz_errno(long v)
+{
+	errno = v;
+	return v == 0 ? 0 : -1;
+}
+#endif
+
+#if SYZ_EXECUTOR || __NR_syz_compare
+#include <errno.h>
+#include <string.h>
+static long syz_compare(long want, long want_len, long got, long got_len)
+{
+	if (want_len != got_len) {
+		debug("syz_compare: want_len=%lu got_len=%lu\n", want_len, got_len);
+		errno = EBADF;
+		return -1;
+	}
+	if (memcmp((void*)want, (void*)got, want_len)) {
+		debug("syz_compare: data differs\n");
+		errno = EINVAL;
+		return -1;
+	}
 	return 0;
 }
 #endif
@@ -3551,8 +3580,37 @@ static int do_sandbox_none(void)
 #include <unistd.h>
 
 #if SYZ_EXECUTOR || __NR_syz_mmap
+#include <sys/mman.h>
 static long syz_mmap(long a0, long a1)
 {
+	return (long)mmap((void*)a0, a1, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE | MAP_FIXED, -1, 0);
+}
+#endif
+
+#if SYZ_EXECUTOR || __NR_syz_errno
+#include <errno.h>
+static long syz_errno(long v)
+{
+	errno = v;
+	return v == 0 ? 0 : -1;
+}
+#endif
+
+#if SYZ_EXECUTOR || __NR_syz_compare
+#include <errno.h>
+#include <string.h>
+static long syz_compare(long want, long want_len, long got, long got_len)
+{
+	if (want_len != got_len) {
+		debug("syz_compare: want_len=%lu got_len=%lu\n", want_len, got_len);
+		errno = EBADF;
+		return -1;
+	}
+	if (memcmp((void*)want, (void*)got, want_len)) {
+		debug("syz_compare: data differs\n");
+		errno = EINVAL;
+		return -1;
+	}
 	return 0;
 }
 #endif
diff --git a/sys/test/exec.txt b/sys/test/exec.txt
new file mode 100644
index 000000000..4d60fa0eb
--- /dev/null
+++ b/sys/test/exec.txt
@@ -0,0 +1,18 @@
+# Copyright 2018 syzkaller project authors. All rights reserved.
+# Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.
+
+syz_mmap(addr vma, len len[addr])
+syz_errno(v int32)
+syz_compare(want ptr[in, string], want_len len[want], got ptr[in, compare_data], got_len len[got])
+
+compare_data [
+	align0	align0
+] [varlen]
+
+align0 {
+	f0	int16
+	f1	int32
+	f2	int8
+	f3	int16
+	f4	int64
+}
diff --git a/sys/test/gen/32_fork_shmem.go b/sys/test/gen/32_fork_shmem.go
index b61c234c1..4b6fd369e 100644
--- a/sys/test/gen/32_fork_shmem.go
+++ b/sys/test/gen/32_fork_shmem.go
@@ -12,9 +12,32 @@ func init() {
 
 var resources_32_fork_shmem = []*ResourceDesc(nil)
 
-var structDescs_32_fork_shmem = []*KeyedStruct(nil)
+var structDescs_32_fork_shmem = []*KeyedStruct{
+	{Key: StructKey{Name: "align0"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "align0", TypeSize: 24}, Fields: []Type{
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f0", TypeSize: 2}}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 2}}, IsPad: true},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3", TypeSize: 2}}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 4}}, IsPad: true},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}}},
+	}}},
+	{Key: StructKey{Name: "compare_data"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "compare_data", IsVarlen: true}, Fields: []Type{
+		&StructType{Key: StructKey{Name: "align0"}, FldName: "align0"},
+	}}},
+}
 
 var syscalls_32_fork_shmem = []*Syscall{
+	{Name: "syz_compare", CallName: "syz_compare", Args: []Type{
+		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "want", TypeSize: 4}, Type: &BufferType{TypeCommon: TypeCommon{TypeName: "string", IsVarlen: true}, Kind: 2}},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "want_len", TypeSize: 4}}, Buf: "want"},
+		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "got", TypeSize: 4}, Type: &UnionType{Key: StructKey{Name: "compare_data"}}},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "got_len", TypeSize: 4}}, Buf: "got"},
+	}},
+	{Name: "syz_errno", CallName: "syz_errno", Args: []Type{
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "v", TypeSize: 4}}},
+	}},
 	{Name: "syz_mmap", CallName: "syz_mmap", Args: []Type{
 		&VmaType{TypeCommon: TypeCommon{TypeName: "vma", FldName: "addr", TypeSize: 4}},
 		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "len", TypeSize: 4}}, Buf: "addr"},
@@ -28,4 +51,4 @@ var consts_32_fork_shmem = []ConstValue{
 	{Name: "ONLY_32BITS_CONST", Value: 1},
 }
 
-const revision_32_fork_shmem = "18f983f4760ca5ac41eaf7c18bd9f487f6dde42b"
+const revision_32_fork_shmem = "d09983a8bb4f2ccd0e303191862d170b5b636bd8"
diff --git a/sys/test/gen/32_shmem.go b/sys/test/gen/32_shmem.go
index 02db6010e..2e26dbb58 100644
--- a/sys/test/gen/32_shmem.go
+++ b/sys/test/gen/32_shmem.go
@@ -12,9 +12,32 @@ func init() {
 
 var resources_32_shmem = []*ResourceDesc(nil)
 
-var structDescs_32_shmem = []*KeyedStruct(nil)
+var structDescs_32_shmem = []*KeyedStruct{
+	{Key: StructKey{Name: "align0"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "align0", TypeSize: 24}, Fields: []Type{
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f0", TypeSize: 2}}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 2}}, IsPad: true},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3", TypeSize: 2}}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 4}}, IsPad: true},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}}},
+	}}},
+	{Key: StructKey{Name: "compare_data"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "compare_data", IsVarlen: true}, Fields: []Type{
+		&StructType{Key: StructKey{Name: "align0"}, FldName: "align0"},
+	}}},
+}
 
 var syscalls_32_shmem = []*Syscall{
+	{Name: "syz_compare", CallName: "syz_compare", Args: []Type{
+		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "want", TypeSize: 4}, Type: &BufferType{TypeCommon: TypeCommon{TypeName: "string", IsVarlen: true}, Kind: 2}},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "want_len", TypeSize: 4}}, Buf: "want"},
+		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "got", TypeSize: 4}, Type: &UnionType{Key: StructKey{Name: "compare_data"}}},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "got_len", TypeSize: 4}}, Buf: "got"},
+	}},
+	{Name: "syz_errno", CallName: "syz_errno", Args: []Type{
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "v", TypeSize: 4}}},
+	}},
 	{Name: "syz_mmap", CallName: "syz_mmap", Args: []Type{
 		&VmaType{TypeCommon: TypeCommon{TypeName: "vma", FldName: "addr", TypeSize: 4}},
 		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "len", TypeSize: 4}}, Buf: "addr"},
@@ -28,4 +51,4 @@ var consts_32_shmem = []ConstValue{
 	{Name: "ONLY_32BITS_CONST", Value: 1},
 }
 
-const revision_32_shmem = "9d4e8ff9d9c38d5fe7cdc046adcde8be29782e6b"
+const revision_32_shmem = "8d0f255b4d310c70d0e7d65ac8e5c6c3032a9e14"
diff --git a/sys/test/gen/64.go b/sys/test/gen/64.go
index b594499c8..58339702f 100644
--- a/sys/test/gen/64.go
+++ b/sys/test/gen/64.go
@@ -21,6 +21,16 @@ var resources_64 = []*ResourceDesc{
 }
 
 var structDescs_64 = []*KeyedStruct{
+	{Key: StructKey{Name: "align0"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "align0", TypeSize: 24}, Fields: []Type{
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f0", TypeSize: 2}}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 2}}, IsPad: true},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3", TypeSize: 2}}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 4}}, IsPad: true},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}}},
+	}}},
 	{Key: StructKey{Name: "any0"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "any0", IsVarlen: true}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1", TypeSize: 1}}},
 		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 3}}, IsPad: true},
@@ -55,6 +65,9 @@ var structDescs_64 = []*KeyedStruct{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "i8", TypeSize: 1}}},
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "i32", TypeSize: 4}}},
 	}}},
+	{Key: StructKey{Name: "compare_data"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "compare_data", IsVarlen: true}, Fields: []Type{
+		&StructType{Key: StructKey{Name: "align0"}, FldName: "align0"},
+	}}},
 	{Key: StructKey{Name: "excessive_fields"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "excessive_fields", TypeSize: 1}, Fields: []Type{
 		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f1", TypeSize: 1}}},
 	}}},
@@ -574,6 +587,15 @@ var syscalls_64 = []*Syscall{
 		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "a", TypeSize: 8}, Type: &BufferType{TypeCommon: TypeCommon{TypeName: "array", ArgDir: 1, IsVarlen: true}}},
 		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "b", TypeSize: 8}}, Buf: "a"},
 	}},
+	{Name: "syz_compare", CallName: "syz_compare", Args: []Type{
+		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "want", TypeSize: 8}, Type: &BufferType{TypeCommon: TypeCommon{TypeName: "string", IsVarlen: true}, Kind: 2}},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "want_len", TypeSize: 8}}, Buf: "want"},
+		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "got", TypeSize: 8}, Type: &UnionType{Key: StructKey{Name: "compare_data"}}},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "got_len", TypeSize: 8}}, Buf: "got"},
+	}},
+	{Name: "syz_errno", CallName: "syz_errno", Args: []Type{
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "v", TypeSize: 4}}},
+	}},
 	{Name: "syz_mmap", CallName: "syz_mmap", Args: []Type{
 		&VmaType{TypeCommon: TypeCommon{TypeName: "vma", FldName: "addr", TypeSize: 8}},
 		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "len", TypeSize: 8}}, Buf: "addr"},
@@ -879,4 +901,4 @@ var consts_64 = []ConstValue{
 	{Name: "SYS_unsupported"},
 }
 
-const revision_64 = "981444b6842c8896801fdf67dc75c454cad9e594"
+const revision_64 = "285bb68296c57fc93062731e5c0ecfbfc105d685"
diff --git a/sys/test/gen/64_fork.go b/sys/test/gen/64_fork.go
index ca62e9ce0..95171623b 100644
--- a/sys/test/gen/64_fork.go
+++ b/sys/test/gen/64_fork.go
@@ -12,9 +12,32 @@ func init() {
 
 var resources_64_fork = []*ResourceDesc(nil)
 
-var structDescs_64_fork = []*KeyedStruct(nil)
+var structDescs_64_fork = []*KeyedStruct{
+	{Key: StructKey{Name: "align0"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "align0", TypeSize: 24}, Fields: []Type{
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f0", TypeSize: 2}}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 2}}, IsPad: true},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "f1", TypeSize: 4}}},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int8", FldName: "f2", TypeSize: 1}}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 1}}, IsPad: true},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int16", FldName: "f3", TypeSize: 2}}},
+		&ConstType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "pad", TypeSize: 4}}, IsPad: true},
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int64", FldName: "f4", TypeSize: 8}}},
+	}}},
+	{Key: StructKey{Name: "compare_data"}, Desc: &StructDesc{TypeCommon: TypeCommon{TypeName: "compare_data", IsVarlen: true}, Fields: []Type{
+		&StructType{Key: StructKey{Name: "align0"}, FldName: "align0"},
+	}}},
+}
 
 var syscalls_64_fork = []*Syscall{
+	{Name: "syz_compare", CallName: "syz_compare", Args: []Type{
+		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "want", TypeSize: 8}, Type: &BufferType{TypeCommon: TypeCommon{TypeName: "string", IsVarlen: true}, Kind: 2}},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "want_len", TypeSize: 8}}, Buf: "want"},
+		&PtrType{TypeCommon: TypeCommon{TypeName: "ptr", FldName: "got", TypeSize: 8}, Type: &UnionType{Key: StructKey{Name: "compare_data"}}},
+		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "got_len", TypeSize: 8}}, Buf: "got"},
+	}},
+	{Name: "syz_errno", CallName: "syz_errno", Args: []Type{
+		&IntType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "int32", FldName: "v", TypeSize: 4}}},
+	}},
 	{Name: "syz_mmap", CallName: "syz_mmap", Args: []Type{
 		&VmaType{TypeCommon: TypeCommon{TypeName: "vma", FldName: "addr", TypeSize: 8}},
 		&LenType{IntTypeCommon: IntTypeCommon{TypeCommon: TypeCommon{TypeName: "len", FldName: "len", TypeSize: 8}}, Buf: "addr"},
@@ -27,4 +50,4 @@ var consts_64_fork = []ConstValue{
 	{Name: "IPPROTO_UDP", Value: 17},
 }
 
-const revision_64_fork = "1c9fe1f1a1f6f871fc5c088ca80174655322aca4"
+const revision_64_fork = "39c2288dd1c825ce7a587f946cfc91e0e453cf5e"
diff --git a/sys/test/test.txt b/sys/test/test.txt
index f35cd7696..d7b822e77 100644
--- a/sys/test/test.txt
+++ b/sys/test/test.txt
@@ -3,7 +3,6 @@
 
 # Syscalls used in syzkaller tests.
 
-syz_mmap(addr vma, len len[addr])
 test()
 
 # Integer types.
diff --git a/sys/test/test/align0 b/sys/test/test/align0
new file mode 100644
index 000000000..ae83c3c84
--- /dev/null
+++ b/sys/test/test/align0
@@ -0,0 +1,3 @@
+syz_compare(&(0x7f0000000000)="010000000200000003000400000000000500000000000000", 0x18, &(0x7f0000001000)=@align0={0x1, 0x2, 0x3, 0x4, 0x5}, 0x18)
+syz_compare(&(0x7f0000000000)="", 0x18, &(0x7f0000001000)=@align0={}, 0x17) # EBADF
+syz_compare(&(0x7f0000000000)="", 0x18, &(0x7f0000001000)=@align0={0x1}, 0x18) # EINVAL
diff --git a/sys/test/test/errno b/sys/test/test/errno
new file mode 100644
index 000000000..8d4905c7e
--- /dev/null
+++ b/sys/test/test/errno
@@ -0,0 +1,7 @@
+syz_errno(0x0)
+syz_errno(0x0)
+syz_errno(0x16)		# EINVAL
+syz_errno(0x0)
+syz_errno(0xc)		# ENOMEM
+syz_errno(0x9)		# EBADF
+syz_errno(0x0)
diff --git a/sys/test/test/test b/sys/test/test/test
index b4d667cd8..1803a6108 100644
--- a/sys/test/test/test
+++ b/sys/test/test/test
@@ -1,3 +1 @@
-syz_mmap()
-syz_mmap()
-syz_mmap()
+syz_mmap() # EINVAL