[newlib-cygwin/main] Cygwin: /proc/<PID>/maps: print real shared region addresses

[newlib-cygwin/main] Cygwin: /proc/<PID>/maps: print real shared region addresses

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=9ddd48ee1b8d736ebbd0b0bdf146ecf96774cd8a

commit 9ddd48ee1b8d736ebbd0b0bdf146ecf96774cd8a
Author:     Corinna Vinschen <corinna@vinschen.de>
AuthorDate: Tue Jan 17 21:58:06 2023 +0100
Commit:     Corinna Vinschen <corinna@vinschen.de>
CommitDate: Tue Jan 17 22:00:48 2023 +0100

    Cygwin: /proc/<PID>/maps: print real shared region addresses
    
    So far, the addresses printed for the shared regions of a process
    were faked.  The assumption was that the shared regions are always
    in the same place in all processes, so we just printed the addresses
    of the current process.  This is no safe bet.  The only safe bet is
    the address of the cygheap.  So keep track of the addresses in the
    cygheap and read the addresses from the cygheap of the observed
    processes.  Add output for the shared console.
    
    Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

Diff:
---
 winsup/cygwin/fhandler/console.cc      |  2 ++
 winsup/cygwin/fhandler/process.cc      | 11 ++++++++---
 winsup/cygwin/local_includes/cygheap.h | 10 ++++++++++
 winsup/cygwin/mm/shared.cc             |  2 ++
 winsup/cygwin/pinfo.cc                 |  2 ++
 5 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/winsup/cygwin/fhandler/console.cc b/winsup/cygwin/fhandler/console.cc
index 68ab43d81ea1..0cbfe4ea41f4 100644
--- a/winsup/cygwin/fhandler/console.cc
+++ b/winsup/cygwin/fhandler/console.cc
@@ -219,6 +219,8 @@ fhandler_console::open_shared_console (HWND hw, HANDLE& h, bool& created)
   shared_locations m = created ? SH_SHARED_CONSOLE : SH_JUSTOPEN;
   console_state *res = (console_state *)
     open_shared (namebuf, 0, h, sizeof (console_state), m, created);
+  if (m == SH_SHARED_CONSOLE)
+    cygheap->shared_regions.console_shared_addr = res;
   return res;
 }
 
diff --git a/winsup/cygwin/fhandler/process.cc b/winsup/cygwin/fhandler/process.cc
index b0aef2ebec00..864e2f4d5009 100644
--- a/winsup/cygwin/fhandler/process.cc
+++ b/winsup/cygwin/fhandler/process.cc
@@ -860,8 +860,11 @@ format_process_maps (void *data, char *&destbuf)
   /* The heap info on the cygheap is also in the same spot in each process
      because the cygheap is located at the same address. */
   user_heap_info user_heap;
+  shared_region_info region_info;
   ReadProcessMemory (proc, &cygheap->user_heap, &user_heap,
 		     sizeof user_heap, NULL);
+  ReadProcessMemory (proc, &cygheap->shared_regions, &region_info,
+		     sizeof region_info, NULL);
 
   off_t len = 0;
 
@@ -1060,12 +1063,14 @@ peb_teb_rinse_repeat:
 		    strcpy (posix_modname, "[peb]");
 		  else if (cur.abase == (char *) &SharedUserData)
 		    strcpy (posix_modname, "[shared-user-data]");
-		  else if (cur.abase == (char *) cygwin_shared)
+		  else if (cur.abase == region_info.cygwin_shared_addr)
 		    strcpy (posix_modname, "[cygwin-shared]");
-		  else if (cur.abase == (char *) user_shared)
+		  else if (cur.abase == region_info.user_shared_addr)
 		    strcpy (posix_modname, "[cygwin-user-shared]");
-		  else if (cur.abase == (char *) *proc_pinfo)
+		  else if (cur.abase == region_info.myself_shared_addr)
 		    strcpy (posix_modname, "[procinfo]");
+		  else if (cur.abase == region_info.console_shared_addr)
+		    strcpy (posix_modname, "[cygwin-shared-console]");
 		  else if (cur.abase == (char *) cygheap)
 		    strcpy (posix_modname, "[cygheap]");
 		  else if (cur.abase == user_heap.base)
diff --git a/winsup/cygwin/local_includes/cygheap.h b/winsup/cygwin/local_includes/cygheap.h
index ceff0fdcf0ba..d885ca123085 100644
--- a/winsup/cygwin/local_includes/cygheap.h
+++ b/winsup/cygwin/local_includes/cygheap.h
@@ -302,6 +302,15 @@ struct user_heap_info
   void init ();
 };
 
+/* This info is maintained for /proc/<PID>/maps ONLY! */
+struct shared_region_info
+{
+  void *cygwin_shared_addr;
+  void *user_shared_addr;
+  void *myself_shared_addr;
+  void *console_shared_addr;
+};
+
 class cygheap_domain_info
 {
   PWCHAR pdom_name;
@@ -503,6 +512,7 @@ struct init_cygheap: public mini_cygheap
   cygheap_ugid_cache ugid_cache;
   cygheap_user user;
   user_heap_info user_heap;
+  shared_region_info shared_regions;
   mode_t umask;
   LONG rlim_as_id;
   unsigned long rlim_core;
diff --git a/winsup/cygwin/mm/shared.cc b/winsup/cygwin/mm/shared.cc
index d23cc8e0e510..d7d6547ec3bb 100644
--- a/winsup/cygwin/mm/shared.cc
+++ b/winsup/cygwin/mm/shared.cc
@@ -274,6 +274,7 @@ user_info::create (bool reinit)
   debug_printf ("user shared version %x", user_shared->version);
   if (reinit)
     user_shared->initialize ();
+  cygheap->shared_regions.user_shared_addr = user_shared;
 }
 
 void
@@ -315,6 +316,7 @@ shared_info::create ()
 					       SH_CYGWIN_SHARED,
 					       &sec_all_nih);
   cygwin_shared->initialize ();
+  cygheap->shared_regions.cygwin_shared_addr = cygwin_shared;
 }
 
 void
diff --git a/winsup/cygwin/pinfo.cc b/winsup/cygwin/pinfo.cc
index c05cf2662cd7..37770b643ef6 100644
--- a/winsup/cygwin/pinfo.cc
+++ b/winsup/cygwin/pinfo.cc
@@ -466,6 +466,8 @@ pinfo::init (pid_t n, DWORD flag, HANDLE h0)
       h = h0;
       _pinfo_release ();
     }
+  if (shloc == SH_MYSELF)
+    cygheap->shared_regions.myself_shared_addr = procinfo;
 }
 
 void