Fix construct of linux.Stat for arm64.

PiperOrigin-RevId: 297494373

8 files changed, 186 insertions, 41 deletions

diff --git a/pkg/sentry/syscalls/linux/BUILD b/pkg/sentry/syscalls/linux/BUILD
index c7883e68e..0d24fd3c4 100644
--- a/pkg/sentry/syscalls/linux/BUILD
+++ b/pkg/sentry/syscalls/linux/BUILD
@@ -42,6 +42,8 @@ go_library(
         "sys_socket.go",
         "sys_splice.go",
         "sys_stat.go",
+        "sys_stat_amd64.go",
+        "sys_stat_arm64.go",
         "sys_sync.go",
         "sys_sysinfo.go",
         "sys_syslog.go",
diff --git a/pkg/sentry/syscalls/linux/sys_stat.go b/pkg/sentry/syscalls/linux/sys_stat.go
index 701b27b4a..9bd2df104 100644
--- a/pkg/sentry/syscalls/linux/sys_stat.go
+++ b/pkg/sentry/syscalls/linux/sys_stat.go
@@ -25,24 +25,6 @@ import (
 
 // LINT.IfChange
 
-func statFromAttrs(t *kernel.Task, sattr fs.StableAttr, uattr fs.UnstableAttr) linux.Stat {
-	return linux.Stat{
-		Dev:     sattr.DeviceID,
-		Ino:     sattr.InodeID,
-		Nlink:   uattr.Links,
-		Mode:    sattr.Type.LinuxType() | uint32(uattr.Perms.LinuxMode()),
-		UID:     uint32(uattr.Owner.UID.In(t.UserNamespace()).OrOverflow()),
-		GID:     uint32(uattr.Owner.GID.In(t.UserNamespace()).OrOverflow()),
-		Rdev:    uint64(linux.MakeDeviceID(sattr.DeviceFileMajor, sattr.DeviceFileMinor)),
-		Size:    uattr.Size,
-		Blksize: sattr.BlockSize,
-		Blocks:  uattr.Usage / 512,
-		ATime:   uattr.AccessTime.Timespec(),
-		MTime:   uattr.ModificationTime.Timespec(),
-		CTime:   uattr.StatusChangeTime.Timespec(),
-	}
-}
-
 // Stat implements linux syscall stat(2).
 func Stat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
 	addr := args[0].Pointer()
diff --git a/pkg/sentry/syscalls/linux/sys_stat_amd64.go b/pkg/sentry/syscalls/linux/sys_stat_amd64.go
new file mode 100644
index 000000000..0a04a6113
--- /dev/null
+++ b/pkg/sentry/syscalls/linux/sys_stat_amd64.go
@@ -0,0 +1,45 @@
+// Copyright 2020 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build amd64
+
+package linux
+
+import (
+	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/sentry/fs"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
+)
+
+// LINT.IfChange
+
+func statFromAttrs(t *kernel.Task, sattr fs.StableAttr, uattr fs.UnstableAttr) linux.Stat {
+	return linux.Stat{
+		Dev:     sattr.DeviceID,
+		Ino:     sattr.InodeID,
+		Nlink:   uattr.Links,
+		Mode:    sattr.Type.LinuxType() | uint32(uattr.Perms.LinuxMode()),
+		UID:     uint32(uattr.Owner.UID.In(t.UserNamespace()).OrOverflow()),
+		GID:     uint32(uattr.Owner.GID.In(t.UserNamespace()).OrOverflow()),
+		Rdev:    uint64(linux.MakeDeviceID(sattr.DeviceFileMajor, sattr.DeviceFileMinor)),
+		Size:    uattr.Size,
+		Blksize: sattr.BlockSize,
+		Blocks:  uattr.Usage / 512,
+		ATime:   uattr.AccessTime.Timespec(),
+		MTime:   uattr.ModificationTime.Timespec(),
+		CTime:   uattr.StatusChangeTime.Timespec(),
+	}
+}
+
+// LINT.ThenChange(vfs2/stat_amd64.go)
diff --git a/pkg/sentry/syscalls/linux/sys_stat_arm64.go b/pkg/sentry/syscalls/linux/sys_stat_arm64.go
new file mode 100644
index 000000000..5a3b1bfad
--- /dev/null
+++ b/pkg/sentry/syscalls/linux/sys_stat_arm64.go
@@ -0,0 +1,45 @@
+// Copyright 2020 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build arm64
+
+package linux
+
+import (
+	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/sentry/fs"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
+)
+
+// LINT.IfChange
+
+func statFromAttrs(t *kernel.Task, sattr fs.StableAttr, uattr fs.UnstableAttr) linux.Stat {
+	return linux.Stat{
+		Dev:     sattr.DeviceID,
+		Ino:     sattr.InodeID,
+		Nlink:   uint32(uattr.Links),
+		Mode:    sattr.Type.LinuxType() | uint32(uattr.Perms.LinuxMode()),
+		UID:     uint32(uattr.Owner.UID.In(t.UserNamespace()).OrOverflow()),
+		GID:     uint32(uattr.Owner.GID.In(t.UserNamespace()).OrOverflow()),
+		Rdev:    uint64(linux.MakeDeviceID(sattr.DeviceFileMajor, sattr.DeviceFileMinor)),
+		Size:    uattr.Size,
+		Blksize: int32(sattr.BlockSize),
+		Blocks:  uattr.Usage / 512,
+		ATime:   uattr.AccessTime.Timespec(),
+		MTime:   uattr.ModificationTime.Timespec(),
+		CTime:   uattr.StatusChangeTime.Timespec(),
+	}
+}
+
+// LINT.ThenChange(vfs2/stat_arm64.go)
diff --git a/pkg/sentry/syscalls/linux/vfs2/BUILD b/pkg/sentry/syscalls/linux/vfs2/BUILD
index f51761e81..e7695e995 100644
--- a/pkg/sentry/syscalls/linux/vfs2/BUILD
+++ b/pkg/sentry/syscalls/linux/vfs2/BUILD
@@ -22,6 +22,8 @@ go_library(
         "read_write.go",
         "setstat.go",
         "stat.go",
+        "stat_amd64.go",
+        "stat_arm64.go",
         "sync.go",
         "xattr.go",
     ],
diff --git a/pkg/sentry/syscalls/linux/vfs2/stat.go b/pkg/sentry/syscalls/linux/vfs2/stat.go
index dca8d7011..12c532310 100644
--- a/pkg/sentry/syscalls/linux/vfs2/stat.go
+++ b/pkg/sentry/syscalls/linux/vfs2/stat.go
@@ -113,29 +113,6 @@ func fstatat(t *kernel.Task, dirfd int32, pathAddr, statAddr usermem.Addr, flags
 	return stat.CopyOut(t, statAddr)
 }
 
-// This takes both input and output as pointer arguments to avoid copying large
-// structs.
-func convertStatxToUserStat(t *kernel.Task, statx *linux.Statx, stat *linux.Stat) {
-	// Linux just copies fields from struct kstat without regard to struct
-	// kstat::result_mask (fs/stat.c:cp_new_stat()), so we do too.
-	userns := t.UserNamespace()
-	*stat = linux.Stat{
-		Dev:     uint64(linux.MakeDeviceID(uint16(statx.DevMajor), statx.DevMinor)),
-		Ino:     statx.Ino,
-		Nlink:   uint64(statx.Nlink),
-		Mode:    uint32(statx.Mode),
-		UID:     uint32(auth.KUID(statx.UID).In(userns).OrOverflow()),
-		GID:     uint32(auth.KGID(statx.GID).In(userns).OrOverflow()),
-		Rdev:    uint64(linux.MakeDeviceID(uint16(statx.RdevMajor), statx.RdevMinor)),
-		Size:    int64(statx.Size),
-		Blksize: int64(statx.Blksize),
-		Blocks:  int64(statx.Blocks),
-		ATime:   timespecFromStatxTimestamp(statx.Atime),
-		MTime:   timespecFromStatxTimestamp(statx.Mtime),
-		CTime:   timespecFromStatxTimestamp(statx.Ctime),
-	}
-}
-
 func timespecFromStatxTimestamp(sxts linux.StatxTimestamp) linux.Timespec {
 	return linux.Timespec{
 		Sec:  sxts.Sec,
diff --git a/pkg/sentry/syscalls/linux/vfs2/stat_amd64.go b/pkg/sentry/syscalls/linux/vfs2/stat_amd64.go
new file mode 100644
index 000000000..2da538fc6
--- /dev/null
+++ b/pkg/sentry/syscalls/linux/vfs2/stat_amd64.go
@@ -0,0 +1,46 @@
+// Copyright 2020 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build amd64
+
+package vfs2
+
+import (
+	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
+	"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
+)
+
+// This takes both input and output as pointer arguments to avoid copying large
+// structs.
+func convertStatxToUserStat(t *kernel.Task, statx *linux.Statx, stat *linux.Stat) {
+	// Linux just copies fields from struct kstat without regard to struct
+	// kstat::result_mask (fs/stat.c:cp_new_stat()), so we do too.
+	userns := t.UserNamespace()
+	*stat = linux.Stat{
+		Dev:     uint64(linux.MakeDeviceID(uint16(statx.DevMajor), statx.DevMinor)),
+		Ino:     statx.Ino,
+		Nlink:   uint64(statx.Nlink),
+		Mode:    uint32(statx.Mode),
+		UID:     uint32(auth.KUID(statx.UID).In(userns).OrOverflow()),
+		GID:     uint32(auth.KGID(statx.GID).In(userns).OrOverflow()),
+		Rdev:    uint64(linux.MakeDeviceID(uint16(statx.RdevMajor), statx.RdevMinor)),
+		Size:    int64(statx.Size),
+		Blksize: int64(statx.Blksize),
+		Blocks:  int64(statx.Blocks),
+		ATime:   timespecFromStatxTimestamp(statx.Atime),
+		MTime:   timespecFromStatxTimestamp(statx.Mtime),
+		CTime:   timespecFromStatxTimestamp(statx.Ctime),
+	}
+}
diff --git a/pkg/sentry/syscalls/linux/vfs2/stat_arm64.go b/pkg/sentry/syscalls/linux/vfs2/stat_arm64.go
new file mode 100644
index 000000000..88b9c7627
--- /dev/null
+++ b/pkg/sentry/syscalls/linux/vfs2/stat_arm64.go
@@ -0,0 +1,46 @@
+// Copyright 2020 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build arm64
+
+package vfs2
+
+import (
+	"gvisor.dev/gvisor/pkg/abi/linux"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
+	"gvisor.dev/gvisor/pkg/sentry/kernel/auth"
+)
+
+// This takes both input and output as pointer arguments to avoid copying large
+// structs.
+func convertStatxToUserStat(t *kernel.Task, statx *linux.Statx, stat *linux.Stat) {
+	// Linux just copies fields from struct kstat without regard to struct
+	// kstat::result_mask (fs/stat.c:cp_new_stat()), so we do too.
+	userns := t.UserNamespace()
+	*stat = linux.Stat{
+		Dev:     uint64(linux.MakeDeviceID(uint16(statx.DevMajor), statx.DevMinor)),
+		Ino:     statx.Ino,
+		Nlink:   uint32(statx.Nlink),
+		Mode:    uint32(statx.Mode),
+		UID:     uint32(auth.KUID(statx.UID).In(userns).OrOverflow()),
+		GID:     uint32(auth.KGID(statx.GID).In(userns).OrOverflow()),
+		Rdev:    uint64(linux.MakeDeviceID(uint16(statx.RdevMajor), statx.RdevMinor)),
+		Size:    int64(statx.Size),
+		Blksize: int32(statx.Blksize),
+		Blocks:  int64(statx.Blocks),
+		ATime:   timespecFromStatxTimestamp(statx.Atime),
+		MTime:   timespecFromStatxTimestamp(statx.Mtime),
+		CTime:   timespecFromStatxTimestamp(statx.Ctime),
+	}
+}