fix(backend): non-login SSH and strict loginctl parse, SSH retry (0.20.31)

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/services/host_sessions.py

@@ -35,6 +35,21 @@ SESSION_EVENT_TYPES_LINUX = frozenset(
 )
 SESSION_EVENT_TYPES_WINDOWS = frozenset({"rdp.login.success"})
 
+_LOGIND_SESSION_ID_RE = re.compile(r"^\d+$|^c\d+$", re.IGNORECASE)
+_LOGIND_USER_RE = re.compile(r"^[a-z_][a-z0-9._-]*$", re.IGNORECASE)
+_LOGIND_STATES = frozenset(
+    {
+        "active",
+        "online",
+        "closing",
+        "opening",
+        "degraded",
+        "lingering",
+        "preparing",
+        "unknown",
+    }
+)
+
 
 @dataclass(frozen=True)
 class HostSessionRow:
@@ -78,14 +93,27 @@ def is_windows_host_event(event: Event) -> bool:
     return host is not None and is_windows_host(host)
 
 
+def _looks_like_loginctl_row(parts: list[str]) -> bool:
+    if len(parts) < 6:
+        return False
+    sid, uid, user, state = parts[0], parts[1], parts[2], parts[5].lower()
+    if not _LOGIND_SESSION_ID_RE.match(sid):
+        return False
+    if not uid.isdigit():
+        return False
+    if not _LOGIND_USER_RE.match(user):
+        return False
+    return state in _LOGIND_STATES
+
+
 def parse_loginctl_sessions(stdout: str) -> list[HostSessionRow]:
     rows: list[HostSessionRow] = []
     for line in stdout.splitlines():
         text = line.strip()
-        if not text:
+        if not text or text.startswith("SESSION"):
             continue
         parts = text.split()
-        if len(parts) < 3:
+        if not _looks_like_loginctl_row(parts):
             continue
         sid, user = parts[0], parts[2]
         tty = parts[4] if len(parts) > 4 and parts[4] != "-" else None
@@ -143,7 +171,7 @@ def list_linux_sessions(host: Host, cfg: LinuxAdminConfig) -> tuple[list[HostSes
     if not is_linux_host(host):
         raise SshHostNotLinuxError("Host is not Linux")
     targets = iter_ssh_targets(host)
-    cmd = "loginctl list-sessions --no-legend --no-pager 2>/dev/null || who -u"
+    cmd = "loginctl list-sessions --no-legend --no-pager"
     last: SshCommandResult | None = None
     for target in targets:
         result = run_ssh_command(
@@ -154,6 +182,7 @@ def list_linux_sessions(host: Host, cfg: LinuxAdminConfig) -> tuple[list[HostSes
             connect_timeout_sec=15,
             command_timeout_sec=45,
             need_root=True,
+            login_shell=False,
         )
         last = result
         if result.ok and result.stdout.strip():
@@ -184,6 +213,7 @@ def terminate_linux_session(
             connect_timeout_sec=15,
             command_timeout_sec=45,
             need_root=True,
+            login_shell=False,
         )
         last = result
         if result.ok:
@@ -286,6 +316,7 @@ def _terminate_linux_user_sessions(host: Host, cfg: LinuxAdminConfig, user: str)
             connect_timeout_sec=15,
             command_timeout_sec=45,
             need_root=True,
+            login_shell=False,
         )
         last = result
         if result.ok: