[binutils-gdb] Refine size constraints applied to win32pstatus ELF notes

[Jon TURNEY]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=04ec0fa297637e6077cdbb735ce6d3c8fde3c9a5

commit 04ec0fa297637e6077cdbb735ce6d3c8fde3c9a5
Author: Jon Turney <jon.turney@dronecode.org.uk>
Date:   Wed Jul 1 16:18:23 2020 +0100

    Refine size constraints applied to win32pstatus ELF notes
    
    Don't reject any win32pstatus notes smaller than minimum size for a
    NOTE_INFO_THREAD.
    
    This only happens to work because the Cygwin dumper tool currently
    writes all these notes as the largest size of the union, (which wastes
    lots of space in the core dump).
    
    Instead, apply the appropriate size constraint for each win32pstatus
    note type.
    
    bfd/ChangeLog:
    
    2020-07-11  Jon Turney  <jon.turney@dronecode.org.uk>
    
            * elf.c (elfcore_grok_win32pstatus): Don't apply size constraint
            for NOTE_INFO_THREAD to all win32pstatus ELF notes, instead apply
            appropriate size constraint for each win32pstatus note type.

Diff:
---
 bfd/ChangeLog |  6 ++++++
 bfd/elf.c     | 17 ++++++++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index c99e654cc20..9b4e74d214e 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,9 @@
+2020-07-11  Jon Turney  <jon.turney@dronecode.org.uk>
+
+	* elf.c (elfcore_grok_win32pstatus): Don't apply size constraint
+	for NOTE_INFO_THREAD to all win32pstatus ELF notes, instead apply
+	appropriate size constraint for each win32pstatus note type.
+
 2020-07-01  Jon Turney  <jon.turney@dronecode.org.uk>
 
 	* elf.c (elfcore_grok_win32pstatus): Don't hardcode the size of
diff --git a/bfd/elf.c b/bfd/elf.c
index 43a6cba89da..171880d6c2a 100644
--- a/bfd/elf.c
+++ b/bfd/elf.c
@@ -10139,12 +10139,13 @@ elfcore_grok_win32pstatus (bfd *abfd, Elf_Internal_Note *note)
   char buf[30];
   char *name;
   size_t len;
+  size_t name_size;
   asection *sect;
   int type;
   int is_active_thread;
   bfd_vma base_addr;
 
-  if (note->descsz < 728)
+  if (note->descsz < 4)
     return TRUE;
 
   if (! CONST_STRNEQ (note->namedata, "win32"))
@@ -10155,12 +10156,18 @@ elfcore_grok_win32pstatus (bfd *abfd, Elf_Internal_Note *note)
   switch (type)
     {
     case NOTE_INFO_PROCESS:
+      if (note->descsz < 12)
+        return FALSE;
+
       /* FIXME: need to add ->core->command.  */
       elf_tdata (abfd)->core->pid = bfd_get_32 (abfd, note->descdata + 4);
       elf_tdata (abfd)->core->signal = bfd_get_32 (abfd, note->descdata + 8);
       break;
 
     case NOTE_INFO_THREAD:
+      if (note->descsz < 12)
+        return FALSE;
+
       /* Make a ".reg/<tid>" section containing the Win32 API thread CONTEXT
          structure. */
       /* thread_info.tid */
@@ -10192,6 +10199,9 @@ elfcore_grok_win32pstatus (bfd *abfd, Elf_Internal_Note *note)
       break;
 
     case NOTE_INFO_MODULE:
+      if (note->descsz < 12)
+        return FALSE;
+
       /* Make a ".module/xxxxxxxx" section.  */
       /* module_info.base_address */
       base_addr = bfd_get_32 (abfd, note->descdata + 4);
@@ -10209,6 +10219,11 @@ elfcore_grok_win32pstatus (bfd *abfd, Elf_Internal_Note *note)
       if (sect == NULL)
 	return FALSE;
 
+      /* module_info.module_name_size */
+      name_size = bfd_get_32 (abfd, note->descdata + 8);
+      if (note->descsz < 12 + name_size)
+        return FALSE;
+
       sect->size = note->descsz;
       sect->filepos = note->descpos;
       sect->alignment_power = 2;