runtime: fix errno sign for some mmap and mincore cases
The caller of mmap expects it to return a positive errno value, but the
linux-arm64 and nacl-386 system calls returned a negative errno value.
Correct them to negate the errno value.
The caller of mincore expects it to return a negative errno value (yes,
this is inconsistent), but the linux-mips64x and linux-ppc64x system
call returned a positive errno value. Correct them to negate the errno
value.
Add a test that mmap returns errno with the correct sign. Brad added a
test for mincore's errno value in https://golang.org/cl/19457.
Fixes #14297.
Change-Id: I2b93f32e679bd1eae1c9aef9ae7bcf0ba39521b5
Reviewed-on: https://go-review.googlesource.com/19455
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/runtime/export_linux_test.go b/src/runtime/export_linux_test.go
index c8b9746..61d6ae4 100644
--- a/src/runtime/export_linux_test.go
+++ b/src/runtime/export_linux_test.go
@@ -7,3 +7,4 @@
package runtime
var NewOSProc0 = newosproc0
+var Mincore = mincore
diff --git a/src/runtime/export_mmap_test.go b/src/runtime/export_mmap_test.go
new file mode 100644
index 0000000..11ea076
--- /dev/null
+++ b/src/runtime/export_mmap_test.go
@@ -0,0 +1,15 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris
+
+// Export guts for testing.
+
+package runtime
+
+var Mmap = mmap
+
+const ENOMEM = _ENOMEM
+const MAP_ANON = _MAP_ANON
+const MAP_PRIVATE = _MAP_PRIVATE
diff --git a/src/runtime/export_test.go b/src/runtime/export_test.go
index b09022b..5400c1d 100644
--- a/src/runtime/export_test.go
+++ b/src/runtime/export_test.go
@@ -28,8 +28,6 @@
var LockedOSThread = lockedOSThread
var Xadduintptr = atomic.Xadduintptr
-var Mincore = mincore
-
var FuncPC = funcPC
var Fastlog2 = fastlog2
diff --git a/src/runtime/mem_bsd.go b/src/runtime/mem_bsd.go
index 1e388ec..c3fe610 100644
--- a/src/runtime/mem_bsd.go
+++ b/src/runtime/mem_bsd.go
@@ -59,9 +59,9 @@
return p
}
-func sysMap(v unsafe.Pointer, n uintptr, reserved bool, sysStat *uint64) {
- const _ENOMEM = 12
+const _ENOMEM = 12
+func sysMap(v unsafe.Pointer, n uintptr, reserved bool, sysStat *uint64) {
mSysStatInc(sysStat, n)
// On 64-bit, we don't actually have v reserved, so tread carefully.
diff --git a/src/runtime/os2_nacl.go b/src/runtime/os2_nacl.go
index 0c91e0f..d8c88db 100644
--- a/src/runtime/os2_nacl.go
+++ b/src/runtime/os2_nacl.go
@@ -10,18 +10,19 @@
// native_client/src/trusted/service_runtime/include/sys/errno.h
// The errors are mainly copied from Linux.
- _EPERM = 1 /* Operation not permitted */
- _ENOENT = 2 /* No such file or directory */
- _ESRCH = 3 /* No such process */
- _EINTR = 4 /* Interrupted system call */
- _EIO = 5 /* I/O error */
- _ENXIO = 6 /* No such device or address */
- _E2BIG = 7 /* Argument list too long */
- _ENOEXEC = 8 /* Exec format error */
- _EBADF = 9 /* Bad file number */
- _ECHILD = 10 /* No child processes */
- _EAGAIN = 11 /* Try again */
- _ENOMEM = 12 /* Out of memory */
+ _EPERM = 1 /* Operation not permitted */
+ _ENOENT = 2 /* No such file or directory */
+ _ESRCH = 3 /* No such process */
+ _EINTR = 4 /* Interrupted system call */
+ _EIO = 5 /* I/O error */
+ _ENXIO = 6 /* No such device or address */
+ _E2BIG = 7 /* Argument list too long */
+ _ENOEXEC = 8 /* Exec format error */
+ _EBADF = 9 /* Bad file number */
+ _ECHILD = 10 /* No child processes */
+ _EAGAIN = 11 /* Try again */
+ // _ENOMEM is defined in mem_bsd.go for nacl.
+ // _ENOMEM = 12 /* Out of memory */
_EACCES = 13 /* Permission denied */
_EFAULT = 14 /* Bad address */
_EBUSY = 16 /* Device or resource busy */
diff --git a/src/runtime/runtime_mmap_test.go b/src/runtime/runtime_mmap_test.go
new file mode 100644
index 0000000..ff5e733
--- /dev/null
+++ b/src/runtime/runtime_mmap_test.go
@@ -0,0 +1,30 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris
+
+package runtime_test
+
+import (
+ "runtime"
+ "runtime/internal/sys"
+ "testing"
+)
+
+// Test that the error value returned by mmap is positive, as that is
+// what the code in mem_bsd.go, mem_darwin.go, and mem_linux.go expects.
+// See the uses of ENOMEM in sysMap in those files.
+func TestMmapErrorSign(t *testing.T) {
+ p := runtime.Mmap(nil, ^uintptr(0)&^(sys.PhysPageSize-1), 0, runtime.MAP_ANON|runtime.MAP_PRIVATE, -1, 0)
+
+ // The runtime.mmap function is nosplit, but t.Errorf is not.
+ // Reset the pointer so that we don't get an "invalid stack
+ // pointer" error from t.Errorf if we call it.
+ v := uintptr(p)
+ p = nil
+
+ if v != runtime.ENOMEM {
+ t.Errorf("mmap = %v, want %v", v, runtime.ENOMEM)
+ }
+}
diff --git a/src/runtime/sys_linux_arm64.s b/src/runtime/sys_linux_arm64.s
index ca0e07a..94c101a 100644
--- a/src/runtime/sys_linux_arm64.s
+++ b/src/runtime/sys_linux_arm64.s
@@ -269,6 +269,9 @@
MOVD $SYS_mmap, R8
SVC
+ CMN $4095, R0
+ BCC 2(PC)
+ NEG R0,R0
MOVD R0, ret+32(FP)
RET
diff --git a/src/runtime/sys_linux_mips64x.s b/src/runtime/sys_linux_mips64x.s
index 6ccb38f..26437dd 100644
--- a/src/runtime/sys_linux_mips64x.s
+++ b/src/runtime/sys_linux_mips64x.s
@@ -168,6 +168,7 @@
MOVV dst+16(FP), R6
MOVV $SYS_mincore, R2
SYSCALL
+ SUBVU R2, R0, R2 // caller expects negative errno
MOVW R2, ret+24(FP)
RET
diff --git a/src/runtime/sys_linux_ppc64x.s b/src/runtime/sys_linux_ppc64x.s
index ba410c5..d063e02 100644
--- a/src/runtime/sys_linux_ppc64x.s
+++ b/src/runtime/sys_linux_ppc64x.s
@@ -153,6 +153,7 @@
MOVD n+8(FP), R4
MOVD dst+16(FP), R5
SYSCALL $SYS_mincore
+ NEG R3 // caller expects negative errno
MOVW R3, ret+24(FP)
RET
diff --git a/src/runtime/sys_nacl_386.s b/src/runtime/sys_nacl_386.s
index bf2d36e..e69a0b7 100644
--- a/src/runtime/sys_nacl_386.s
+++ b/src/runtime/sys_nacl_386.s
@@ -227,6 +227,9 @@
LEAL 24(SP), AX
MOVL AX, 20(SP)
NACL_SYSCALL(SYS_mmap)
+ CMPL AX, $-4095
+ JNA 2(PC)
+ NEGL AX
MOVL AX, ret+24(FP)
RET
