gdb/SOURCES/gdb-rhbz1842691-corefile-mem-access-10of15.patch

From FEDORA_PATCHES Mon Sep 17 00:00:00 2001
From: Keith Seitz <keiths@redhat.com>
Date: Mon, 27 Jul 2020 19:38:20 -0400
Subject: gdb-rhbz1842691-corefile-mem-access-10of15.patch

;; gcore command: Place all file-backed mappings in NT_FILE note
;; Kevin Buettner, RH BZ 1842961

   Author: Kevin Buettner <kevinb@redhat.com>
   Date:   Wed Jul 1 06:34:50 2020 -0700

    gcore command: Place all file-backed mappings in NT_FILE note

    When making a core file with the GDB's gcore command on Linux,
    the same criteria used for determining which mappings should be
    dumped were also being used for determining which entries should
    be placed in the NT_FILE note.  This is wrong; we want to place
    all file-backed mappings in this note.

    The predicate function, dump_mapping_p, was used to determine whether
    or not to dump a mapping from within linux_find_memory_regions_full.
    This commit leaves this predicate in place, but adds a new parameter,
    should_dump_mapping_p, to linux_find_memory_regions_full.  It then
    calls should_dump_mapping_p instead of dump_mapping_p.  dump_mapping_p
    is passed to linux_find_memory_regions_full at one call site; at the
    other call site, dump_note_entry_p is passed instead.

    gdb/ChangeLog:

    	* linux-tdep.c (dump_note_entry_p): New function.
    	(linux_dump_mapping_p_ftype): New typedef.
    	(linux_find_memory_regions_full): Add new parameter,
    	should_dump_mapping_p.
    	(linux_find_memory_regions): Adjust call to
    	linux_find_memory_regions_full.
    	(linux_make_mappings_core_file_notes): Use dump_note_entry_p in
    	call to linux_find_memory_regions_full.

diff --git a/gdb/linux-tdep.c b/gdb/linux-tdep.c
--- a/gdb/linux-tdep.c
+++ b/gdb/linux-tdep.c
@@ -710,6 +710,25 @@ dump_mapping_p (filter_flags filterflags, const struct smaps_vmflags *v,
     }
 }
 
+/* As above, but return true only when we should dump the NT_FILE
+   entry.  */
+
+static int
+dump_note_entry_p (filter_flags filterflags, const struct smaps_vmflags *v,
+		int maybe_private_p, int mapping_anon_p, int mapping_file_p,
+		const char *filename)
+{
+  /* vDSO and vsyscall mappings will end up in the core file.  Don't
+     put them in the NT_FILE note.  */
+  if (strcmp ("[vdso]", filename) == 0
+      || strcmp ("[vsyscall]", filename) == 0)
+    return 0;
+
+  /* Otherwise, any other file-based mapping should be placed in the
+     note.  */
+  return filename != nullptr;
+}
+
 /* Implement the "info proc" command.  */
 
 static void
@@ -1224,10 +1243,18 @@ typedef int linux_find_memory_region_ftype (ULONGEST vaddr, ULONGEST size,
 					    const char *filename,
 					    void *data);
 
+typedef int linux_dump_mapping_p_ftype (filter_flags filterflags,
+					const struct smaps_vmflags *v,
+					int maybe_private_p,
+					int mapping_anon_p,
+					int mapping_file_p,
+					const char *filename);
+
 /* List memory regions in the inferior for a corefile.  */
 
 static int
 linux_find_memory_regions_full (struct gdbarch *gdbarch,
+				linux_dump_mapping_p_ftype *should_dump_mapping_p,
 				linux_find_memory_region_ftype *func,
 				void *obfd)
 {
@@ -1378,7 +1405,7 @@ linux_find_memory_regions_full (struct gdbarch *gdbarch,
 	    }
 
 	  if (has_anonymous)
-	    should_dump_p = dump_mapping_p (filterflags, &v, priv,
+	    should_dump_p = should_dump_mapping_p (filterflags, &v, priv,
 					    mapping_anon_p, mapping_file_p,
 					    filename);
 	  else
@@ -1444,6 +1471,7 @@ linux_find_memory_regions (struct gdbarch *gdbarch,
   data.obfd = obfd;
 
   return linux_find_memory_regions_full (gdbarch,
+					 dump_mapping_p,
 					 linux_find_memory_regions_thunk,
 					 &data);
 }
@@ -1606,7 +1634,9 @@ linux_make_mappings_corefile_notes (struct gdbarch *gdbarch, bfd *obfd,
   pack_long (buf, long_type, 1);
   obstack_grow (&data_obstack, buf, TYPE_LENGTH (long_type));
 
-  linux_find_memory_regions_full (gdbarch, linux_make_mappings_callback,
+  linux_find_memory_regions_full (gdbarch, 
+				  dump_note_entry_p,
+				  linux_make_mappings_callback,
 				  &mapping_data);
 
   if (mapping_data.file_count != 0)