Linux: Add stat method for FdLike

.coveragerc

@@ -2,3 +2,11 @@
 source = manticore
 omit =
 	*__init__.py
+
+[report]
+exclude_lines =
+    # Have to re-enable the standard pragma
+    pragma: no cover
+
+    # Don't try to cover special syntax "..." in abstract class
+    @abstractmethod

manticore/platforms/linux.py

@@ -105,6 +105,30 @@ class creation time, you will get an error only if you try to instantiate
     return cls
 
 
+@dataclass
+class StatResult:
+    """
+    Data structure corresponding to result received from stat, fstat, lstat for
+    information about a file.
+
+    See https://man7.org/linux/man-pages/man2/stat.2.html for more info
+    """
+
+    st_mode: int
+    st_ino: int
+    st_dev: int
+    st_nlink: int
+    st_uid: int
+    st_gid: int
+    st_size: int
+    st_atime: int
+    st_mtime: int
+    st_ctime: int
+    st_blksize: int
+    st_blocks: int
+    st_rdev: int
+
+
 class FdLike(ABC):
     """
     An abstract class for different kinds of file descriptors.
@@ -142,6 +166,10 @@ def ioctl(self, request, argp) -> int:
     def tell(self) -> int:
         ...
 
+    @abstractmethod
+    def stat(self) -> StatResult:
+        ...
+
 
 @dataclass
 class FdTableEntry:
@@ -277,9 +305,9 @@ def closed(self) -> bool:
 
     def stat(self):
         try:
-            return os.fstat(self.fileno())
+            return os.stat(self.fileno())
         except OSError as e:
-            return -e.errno
+            raise FdError(f"Cannot stat: {e.strerror}", e.errno)
 
     def ioctl(self, request, argp):
         try:
@@ -375,6 +403,12 @@ def close(self):
         except OSError as e:
             return -e.errno
 
+    def stat(self):
+        try:
+            return os.stat(self.fileno())
+        except OSError as e:
+            raise FdError(f"Cannot stat: {e.strerror}", e.errno)
+
     def fileno(self):
         return self.fd
 
@@ -541,31 +575,17 @@ def ioctl(self, request, argp):
     def tell(self) -> int:
         raise FdError("Invalid tell() operation on SocketDesc", errno.EBADF)
 
+    def stat(self) -> StatResult:
+        # Copied from Socket.stat
+        return StatResult(
+            8592, 11, 9, 1, 1000, 5, 0, 1378673920, 1378673920, 1378653796, 0x400, 0x8808, 0
+        )
+
 
 @concreteclass
 class Socket(FdLike):
     def stat(self):
-        from collections import namedtuple
-
-        stat_result = namedtuple(
-            "stat_result",
-            [
-                "st_mode",
-                "st_ino",
-                "st_dev",
-                "st_nlink",
-                "st_uid",
-                "st_gid",
-                "st_size",
-                "st_atime",
-                "st_mtime",
-                "st_ctime",
-                "st_blksize",
-                "st_blocks",
-                "st_rdev",
-            ],
-        )
-        return stat_result(
+        return StatResult(
             8592, 11, 9, 1, 1000, 5, 0, 1378673920, 1378673920, 1378653796, 0x400, 0x8808, 0
         )
 
@@ -3051,8 +3071,10 @@ def sys_getdents(self, fd, dirent, count) -> int:
                 # Don't overflow buffer
                 break
 
-            stat = item.stat()
-            print(f"FILE MODE: {item.name} :: {stat.st_mode:o}")
+            try:
+                stat = item.stat()
+            except FdError as e:
+                return -e.err
 
             # https://elixir.bootlin.com/linux/v5.1.15/source/include/linux/fs_types.h#L27
             d_type = (stat.st_mode >> 12) & 15

tests/native/test_syscalls.py

@@ -91,6 +91,180 @@ def test_directories(self):
         self.linux.sys_rmdir(0x1100)
         self.assertFalse(os.path.exists(dname))
 
+    def test_dir_stat(self):
+        dname = self.get_path("test_dir_stat")
+        self.assertFalse(os.path.exists(dname))
+
+        self.linux.current.memory.mmap(0x1000, 0x1000, "rw")
+        self.linux.current.write_string(0x1100, dname)
+
+        # Create it as a dir
+        self.linux.sys_mkdir(0x1100, mode=0o777)
+        fd = self.linux.sys_open(0x1100, flags=os.O_RDONLY | os.O_DIRECTORY, mode=0o777)
+        self.assertTrue(os.path.exists(dname))
+        self.assertGreater(fd, 0)
+
+        res = self.linux.sys_stat32(0x1100, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_stat64(0x1100, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_newfstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat64(fd, 0x1200)
+        self.assertEqual(res, 0)
+
+        # Remove from file system on host but not in Manticore
+        os.rmdir(dname)
+        self.assertFalse(os.path.exists(dname))
+        res = self.linux.sys_stat32(0x1100, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_stat64(0x1100, 0x1200)
+        self.assertLess(res, 0)
+        # The file descriptor is still valid even though the directory is gone
+        res = self.linux.sys_newfstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat64(fd, 0x1200)
+        self.assertEqual(res, 0)
+
+        # Remove the directory using Manticore
+        self.linux.sys_rmdir(0x1100)
+        res = self.linux.sys_stat32(0x1100, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_stat64(0x1100, 0x1200)
+        self.assertLess(res, 0)
+        # The file descriptor is still valid even though the directory is gone
+        res = self.linux.sys_newfstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat64(fd, 0x1200)
+        self.assertEqual(res, 0)
+
+        # Close the file descriptor to totally remove it
+        self.linux.sys_close(fd)
+        res = self.linux.sys_stat32(0x1100, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_stat64(0x1100, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_newfstat(fd, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_fstat(fd, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_fstat64(fd, 0x1200)
+        self.assertLess(res, 0)
+
+    def test_file_stat(self):
+        fname = self.get_path("test_file_stat")
+        self.assertFalse(os.path.exists(fname))
+
+        self.linux.current.memory.mmap(0x1000, 0x1000, "rw")
+        self.linux.current.write_string(0x1100, fname)
+
+        # Create a file
+        fd = self.linux.sys_open(0x1100, os.O_RDWR, 0o777)
+        self.assertTrue(os.path.exists(fname))
+
+        res = self.linux.sys_stat32(0x1100, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_stat64(0x1100, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_newfstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat64(fd, 0x1200)
+        self.assertEqual(res, 0)
+
+        # Remove from file system on host but not in Manticore
+        os.remove(fname)
+        self.assertFalse(os.path.exists(fname))
+        res = self.linux.sys_stat32(0x1100, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_stat64(0x1100, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_newfstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat64(fd, 0x1200)
+        self.assertEqual(res, 0)
+
+        # Remove the file using Manticore
+        self.linux.sys_unlink(0x1100)
+        res = self.linux.sys_stat32(0x1100, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_stat64(0x1100, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_newfstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat64(fd, 0x1200)
+        self.assertEqual(res, 0)
+
+        # Close the file descriptor to totally remove it
+        self.linux.sys_close(fd)
+        res = self.linux.sys_stat32(0x1100, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_stat64(0x1100, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_newfstat(fd, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_fstat(fd, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_fstat64(fd, 0x1200)
+        self.assertLess(res, 0)
+
+    def test_socketdesc_stat(self):
+        self.linux.current.memory.mmap(0x1000, 0x1000, "rw")
+
+        # Create a socket
+        fd = self.linux.sys_socket(socket.AF_INET, socket.SOCK_STREAM, 0)
+        res = self.linux.sys_newfstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat(fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat64(fd, 0x1200)
+        self.assertEqual(res, 0)
+
+        # Close the socket
+        self.linux.sys_close(fd)
+        res = self.linux.sys_newfstat(fd, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_fstat(fd, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_fstat64(fd, 0x1200)
+        self.assertLess(res, 0)
+
+    def test_socket_stat(self):
+        self.linux.current.memory.mmap(0x1000, 0x1000, "rw")
+
+        # Create a socket
+        sock_fd = self.linux.sys_socket(socket.AF_INET, socket.SOCK_STREAM, 0)
+        self.linux.sys_bind(sock_fd, None, None)
+        self.linux.sys_listen(sock_fd, None)
+        conn_fd = self.linux.sys_accept(sock_fd, None, 0)
+
+        res = self.linux.sys_newfstat(conn_fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat(conn_fd, 0x1200)
+        self.assertEqual(res, 0)
+        res = self.linux.sys_fstat64(conn_fd, 0x1200)
+        self.assertEqual(res, 0)
+
+        # Close the socket
+        self.linux.sys_close(conn_fd)
+        res = self.linux.sys_newfstat(conn_fd, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_fstat(conn_fd, 0x1200)
+        self.assertLess(res, 0)
+        res = self.linux.sys_fstat64(conn_fd, 0x1200)
+        self.assertLess(res, 0)
+
     def test_pipe(self):
         self.linux.current.memory.mmap(0x1000, 0x1000, "rw")
         self.linux.sys_pipe(0x1100)