[rpms/gdb] gdb-17.2-rebase-f44: Backport upstream fix for RHBZ 2196395

[rpms/gdb] gdb-17.2-rebase-f44: Backport upstream fix for RHBZ 2196395

[Andrew Burgess]

            A new commit has been pushed.

            Repo   : rpms/gdb
            Branch : gdb-17.2-rebase-f44
            Commit : 899498bb21a76308674df73687ca643618c15bea
            Author : Andrew Burgess <aburgess@redhat.com>
            Date   : 2023-08-03T09:29:19+01:00
            Stats  : +197/-0 in 5 file(s)
            URL    : https://src.fedoraproject.org/rpms/gdb/c/899498bb21a76308674df73687ca643618c15bea?branch=gdb-17.2-rebase-f44

            Log:
            Backport upstream fix for RHBZ 2196395

Backport upstream commit f3eee5861743d635 to fix a crash triggered
when debuginfod makes use of particular openssl settings.

---
diff --git a/_gdb.spec.Patch.include b/_gdb.spec.Patch.include
index 0b464fd..38901e1 100644
--- a/_gdb.spec.Patch.include
+++ b/_gdb.spec.Patch.include
@@ -207,3 +207,7 @@ Patch046: gdb-rhbz2192105-ftbs-dangling-pointer
 # core file. (RH BZ 2160211)
 Patch047: gdb-rhbz2160211-excessive-core-file-warnings.patch
 
+# Backport upstream commit f3eee5861743d635 to fix a crash triggered
+# when debuginfod makes use of particular openssl settings.
+Patch048: gdb-bz2196395-debuginfod-legacy-openssl-crash.patch
+

diff --git a/_gdb.spec.patch.include b/_gdb.spec.patch.include
index 8258dc9..ef55dd0 100644
--- a/_gdb.spec.patch.include
+++ b/_gdb.spec.patch.include
@@ -45,3 +45,4 @@
 %patch -p1 -P045
 %patch -p1 -P046
 %patch -p1 -P047
+%patch -p1 -P048

diff --git a/_patch_order b/_patch_order
index 51c4581..143a63e 100644
--- a/_patch_order
+++ b/_patch_order
@@ -45,3 +45,4 @@ gdb-rhbz1553104-s390x-arch12-test.patch
 gdb-binutils29988-read_indexed_address.patch
 gdb-rhbz2192105-ftbs-dangling-pointer
 gdb-rhbz2160211-excessive-core-file-warnings.patch
+gdb-bz2196395-debuginfod-legacy-openssl-crash.patch

diff --git a/gdb-bz2196395-debuginfod-legacy-openssl-crash.patch b/gdb-bz2196395-debuginfod-legacy-openssl-crash.patch
new file mode 100644
index 0000000..452fe58
--- /dev/null
+++ b/gdb-bz2196395-debuginfod-legacy-openssl-crash.patch
@@ -0,0 +1,188 @@
+From FEDORA_PATCHES Mon Sep 17 00:00:00 2001
+From: Andrew Burgess <aburgess@redhat.com>
+Date: Tue, 20 Jun 2023 09:46:35 +0100
+Subject: gdb-bz2196395-debuginfod-legacy-openssl-crash.patch
+
+;; Backport upstream commit f3eee5861743d635 to fix a crash triggered
+;; when debuginfod makes use of particular openssl settings.
+
+gdb/debuginfod: cleanup debuginfod earlier
+
+A GDB crash was discovered on Fedora GDB that was tracked back to an
+issue with the way that debuginfod is cleaned up.
+
+The bug was reported on Fedora 37, 38, and 39.  Here are the steps to
+reproduce:
+
+1. The file /etc/ssl/openssl.cnf contains the following lines:
+
+   [provider_sect]
+   default = default_sect
+   ##legacy = legacy_sect
+   ##
+   [default_sect]
+   activate = 1
+
+   ##[legacy_sect]
+   ##activate = 1
+
+   The bug will occur when the '##' characters are removed so that the
+   lines in question look like this:
+
+   [provider_sect]
+   default = default_sect
+   legacy = legacy_sect
+
+   [default_sect]
+   activate = 1
+
+   [legacy_sect]
+   activate = 1
+
+2. Clean up any existing debuginfod cache data:
+
+   > rm -rf $HOME/.cache/debuginfod_client
+
+3. Run GDB:
+
+   > gdb -nx -q -iex 'set trace-commands on' \
+                -iex 'set debuginfod enabled on' \
+                -iex 'set confirm off' \
+                -ex 'start' -ex 'quit' /bin/ls
+   +set debuginfod enabled on
+   +set confirm off
+   Reading symbols from /bin/ls...
+   Downloading separate debug info for /usr/bin/ls
+   ... snip ...
+   Temporary breakpoint 1, main (argc=1, argv=0x7fffffffde38) at ../src/ls.c:1646
+   1646    {
+   +quit
+
+   Fatal signal: Segmentation fault
+   ----- Backtrace -----
+   ... snip ...
+
+So GDB ends up crashing during exit.
+
+What's happening is that when debuginfod is initialised
+debuginfod_begin is called (this is in the debuginfod library), this
+in turn sets up libcurl, which makes use of openssl.  Somewhere during
+this setup process an at_exit function is registered to cleanup some
+state.
+
+Back in GDB the debuginfod_client object is managed using this code:
+
+  /* Deleter for a debuginfod_client.  */
+
+  struct debuginfod_client_deleter
+  {
+    void operator() (debuginfod_client *c)
+    {
+      debuginfod_end (c);
+    }
+  };
+
+  using debuginfod_client_up
+    = std::unique_ptr<debuginfod_client, debuginfod_client_deleter>;
+
+And then a global debuginfod_client_up is created to hold a pointer to
+the debuginfod_client object.  As a global this will be cleaned up
+using the standard C++ global object destructor mechanism, which is
+run after the at_exit handlers.
+
+However, it is expected that when debuginfod_end is called the
+debuginfod_client object will still be in a usable state, that is, we
+don't expect the at_exit handlers to have run and started cleaning up
+the library state.
+
+To fix this issue we need to ensure that debuginfod_end is called
+before the at_exit handlers have a chance to run.
+
+This commit removes the debuginfod_client_up type, and instead has GDB
+hold a raw pointer to the debuginfod_client object.  We then make use
+of GDB's make_final_cleanup to register a function that will call
+debuginfod_end.
+
+As GDB's final cleanups are called before exit is called, this means
+that debuginfod_end will be called before the at_exit handlers are
+called, and the crash identified above is resolved.
+
+It's not obvious how this issue can easily be tested for. The bug does
+not appear to manifest when using a local debuginfod server, so we'd
+need to setup something more involved.  For now I'm proposing this
+patch without any associated tests.
+
+diff --git a/gdb/debuginfod-support.c b/gdb/debuginfod-support.c
+--- a/gdb/debuginfod-support.c
++++ b/gdb/debuginfod-support.c
+@@ -96,20 +96,6 @@ struct user_data
+   ui_out::progress_update progress;
+ };
+ 
+-/* Deleter for a debuginfod_client.  */
+-
+-struct debuginfod_client_deleter
+-{
+-  void operator() (debuginfod_client *c)
+-  {
+-    debuginfod_end (c);
+-  }
+-};
+-
+-using debuginfod_client_up
+-  = std::unique_ptr<debuginfod_client, debuginfod_client_deleter>;
+-
+-
+ /* Convert SIZE into a unit suitable for use with progress updates.
+    SIZE should in given in bytes and will be converted into KB, MB, GB
+    or remain unchanged. UNIT will be set to "B", "KB", "MB" or "GB"
+@@ -180,20 +166,45 @@ progressfn (debuginfod_client *c, long cur, long total)
+   return 0;
+ }
+ 
++/* Cleanup ARG, which is a debuginfod_client pointer.  */
++
++static void
++cleanup_debuginfod_client (void *arg)
++{
++  debuginfod_client *client = static_cast<debuginfod_client *> (arg);
++  debuginfod_end (client);
++}
++
++/* Return a pointer to the single global debuginfod_client, initialising it
++   first if needed.  */
++
+ static debuginfod_client *
+ get_debuginfod_client ()
+ {
+-  static debuginfod_client_up global_client;
++  static debuginfod_client *global_client = nullptr;
+ 
+   if (global_client == nullptr)
+     {
+-      global_client.reset (debuginfod_begin ());
++      global_client = debuginfod_begin ();
+ 
+       if (global_client != nullptr)
+-	debuginfod_set_progressfn (global_client.get (), progressfn);
++	{
++	  /* It is important that we cleanup the debuginfod_client object
++	     before calling exit.  Some of the libraries used by debuginfod
++	     make use of at_exit handlers to perform cleanup.
++
++	     If we wrapped the debuginfod_client in a unique_ptr and relied
++	     on its destructor to cleanup then this would be run as part of
++	     the global C++ object destructors, which is after the at_exit
++	     handlers, which is too late.
++
++	     So instead, we make use of GDB's final cleanup mechanism.  */
++	  make_final_cleanup (cleanup_debuginfod_client, global_client);
++	  debuginfod_set_progressfn (global_client, progressfn);
++	}
+     }
+ 
+-  return global_client.get ();
++  return global_client;
+ }
+ 
+ /* Check if debuginfod is enabled.  If configured to do so, ask the user

diff --git a/gdb.spec b/gdb.spec
index 4797705..7653b86 100644
--- a/gdb.spec
+++ b/gdb.spec
@@ -1252,6 +1252,9 @@ fi
 %endif
 
 %changelog
+* Thu Aug  3 2023 Andrew Burgess <aburgess@redhat.com>
+- Backport upstream commit f3eee586174, which fixes RHBZ 2196395.
+
 * Wed Jul 19 2023 Fedora Release Engineering <releng@fedoraproject.org>
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_39_Mass_Rebuild