From 2855c35c41ed5c950e40ce0ae0d99d00185e05ad Mon Sep 17 00:00:00 2001
From: Corinna Vinschen <corinna@vinschen.de>
Date: Tue, 9 Apr 2024 16:52:58 +0200
Subject: [PATCH] Cygwin: fhandler_virtual::exists: always set fileid

Commit a0a25849f9dd ("Cygwin: fhandler_virtual: move fileid to path_conv
member") broke `ls -l /proc/<PID>'.  Turns out, the commit forgot to set
the fileid in case of a virtual root dir (i. e., returning virt_rootdir)
in fhandlers utilizing fileid.  This crashed opendir() due to a random
fileid.

Make sure to set fileid in any case.

Fixes: a0a25849f9dd ("Cygwin: fhandler_virtual: move fileid to path_conv member")
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
---
 winsup/cygwin/fhandler/proc.cc        | 6 +++++-
 winsup/cygwin/fhandler/process.cc     | 6 +++++-
 winsup/cygwin/fhandler/procnet.cc     | 6 +++++-
 winsup/cygwin/fhandler/procsysvipc.cc | 6 +++++-
 4 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/winsup/cygwin/fhandler/proc.cc b/winsup/cygwin/fhandler/proc.cc
index 7629b54d2..baf0cae1e 100644
--- a/winsup/cygwin/fhandler/proc.cc
+++ b/winsup/cygwin/fhandler/proc.cc
@@ -180,7 +180,10 @@ fhandler_proc::exists ()
   debug_printf ("exists (%s)", path);
   path += proc_len;
   if (*path == 0)
-    return virt_rootdir;
+    {
+      fileid () = 0;
+      return virt_rootdir;
+    }
   virt_tab_t *entry = virt_tab_search (path + 1, false, proc_tab,
 				       PROC_LINK_COUNT);
   if (entry)
@@ -188,6 +191,7 @@ fhandler_proc::exists ()
       fileid () = entry - proc_tab;
       return entry->type;
     }
+  fileid () = -1;
   return virt_none;
 }
 
diff --git a/winsup/cygwin/fhandler/process.cc b/winsup/cygwin/fhandler/process.cc
index 20169d22f..37bdff84e 100644
--- a/winsup/cygwin/fhandler/process.cc
+++ b/winsup/cygwin/fhandler/process.cc
@@ -95,7 +95,10 @@ fhandler_process::exists ()
   while (*path != 0 && !isdirsep (*path))
     path++;
   if (*path == 0)
-    return virt_rootdir;
+    {
+      fileid () = 0;
+      return virt_rootdir;
+    }
 
   virt_tab_t *entry = virt_tab_search (path + 1, true, process_tab,
 				       PROCESS_LINK_COUNT);
@@ -122,6 +125,7 @@ fhandler_process::exists ()
 	    }
 	}
     }
+  fileid () = -1;
   return virt_none;
 }
 
diff --git a/winsup/cygwin/fhandler/procnet.cc b/winsup/cygwin/fhandler/procnet.cc
index 112aee8a2..631fe8cc1 100644
--- a/winsup/cygwin/fhandler/procnet.cc
+++ b/winsup/cygwin/fhandler/procnet.cc
@@ -48,7 +48,10 @@ fhandler_procnet::exists ()
   while (*path != 0 && !isdirsep (*path))
     path++;
   if (*path == 0)
-    return virt_rootdir;
+    {
+      fileid () = 0;
+      return virt_rootdir;
+    }
 
   virt_tab_t *entry = virt_tab_search (path + 1, false, procnet_tab,
 				       PROCNET_LINK_COUNT);
@@ -59,6 +62,7 @@ fhandler_procnet::exists ()
       fileid () = entry - procnet_tab;
       return entry->type;
     }
+  fileid () = -1;
   return virt_none;
 }
 
diff --git a/winsup/cygwin/fhandler/procsysvipc.cc b/winsup/cygwin/fhandler/procsysvipc.cc
index b322c4601..dac565c07 100644
--- a/winsup/cygwin/fhandler/procsysvipc.cc
+++ b/winsup/cygwin/fhandler/procsysvipc.cc
@@ -61,7 +61,10 @@ fhandler_procsysvipc::exists ()
   while (*path != 0 && !isdirsep (*path))
     path++;
   if (*path == 0)
-    return virt_rootdir;
+    {
+      fileid () = 0;
+      return virt_rootdir;
+    }
 
   virt_tab_t *entry = virt_tab_search (path + 1, true, procsysvipc_tab,
 				       PROCSYSVIPC_LINK_COUNT);
@@ -78,6 +81,7 @@ fhandler_procsysvipc::exists ()
 	  fileid () = entry - procsysvipc_tab;
 	  return entry->type;
 	}
+  fileid () = -1;
   return virt_none;
 }
 
-- 
2.43.5