commit 217cbb0055391809d6dfb56cec053fdd3cf08b75
author Alan Modra <amodra@gmail.com> Tue Aug 02 16:53:54 2022 +0930
committer Alan Modra <amodra@gmail.com> Tue Aug 02 17:01:56 2022 +0930
tree 2b6d348d7757ff4b568fe77da084af9e8017e5dc
parent d2dcf3908f2b1da5bc84eaef61d7b758d07009a6

PE objdump -x

objdump -x on PE executables produces lots of "xdata section corrupt"
and "corrupt unwind data" warnings, and refuses to dump that info.  It
turns out that the sanity checks were bad, not the data.  Fix them.

	* pei-x86_64.c (pex64_get_unwind_info): Correct buffer overrun
	sanity checks.
	(pex64_xdata_print_uwd_codes): Similarly.

bfd/pei-x86_64.c

diff --git a/bfd/pei-x86_64.c b/bfd/pei-x86_64.c
index 7d8fc8f..795bf66 100644
--- a/bfd/pei-x86_64.c
+++ b/bfd/pei-x86_64.c
@@ -109,7 +109,7 @@
 
   memset (ui, 0, sizeof (struct pex64_unwind_info));
 
-  if (ex_dta >= ex_dta_end || ex_dta + 4 >= ex_dta_end)
+  if (ex_dta >= ex_dta_end || ex_dta + 4 > ex_dta_end)
     return false;
 
   ui->Version = PEX64_UWI_VERSION (ex_ui->Version_Flags);
@@ -124,13 +124,13 @@
   ui->rawUnwindCodesEnd = ex_dta_end;
 
   ex_dta += ui->SizeOfBlock;
-  if (ex_dta >= ex_dta_end)
+  if (ex_dta > ex_dta_end)
     return false;
 
   switch (ui->Flags)
     {
     case UNW_FLAG_CHAININFO:
-      if (ex_dta + 12 >= ex_dta_end)
+      if (ex_dta + 12 > ex_dta_end)
 	return false;
       ui->rva_BeginAddress = bfd_get_32 (abfd, ex_dta + 0);
       ui->rva_EndAddress = bfd_get_32 (abfd, ex_dta + 4);
@@ -140,7 +140,7 @@
     case UNW_FLAG_EHANDLER:
     case UNW_FLAG_UHANDLER:
     case UNW_FLAG_FHANDLER:
-      if (ex_dta + 4 >= ex_dta_end)
+      if (ex_dta + 4 > ex_dta_end)
 	return false;
       ui->rva_ExceptionHandler = bfd_get_32 (abfd, ex_dta);
       ui->SizeOfBlock += 4;
@@ -172,7 +172,7 @@
 
   i = 0;
 
-  if (ui->rawUnwindCodes + 1 >= ui->rawUnwindCodesEnd)
+  if (ui->rawUnwindCodes + ui->CountOfCodes * 2 > ui->rawUnwindCodesEnd)
     {
       fprintf (file, _("warning: corrupt unwind data\n"));
       return;
@@ -186,12 +186,6 @@
 	 to decode instruction flow if outside an epilog.  */
       unsigned int func_size = rf->rva_EndAddress - rf->rva_BeginAddress;
 
-      if (ui->rawUnwindCodes + 1 + (ui->CountOfCodes * 2) >= ui->rawUnwindCodesEnd)
-	{
-	  fprintf (file, _("warning: corrupt unwind data\n"));
-	  return;
-	}
-
       fprintf (file, "\tv2 epilog (length: %02x) at pc+:",
 	       ui->rawUnwindCodes[0]);
 
@@ -215,12 +209,6 @@
       fputc ('\n', file);
     }
 
-  if (ui->rawUnwindCodes + 2 + (ui->CountOfCodes * 2) >= ui->rawUnwindCodesEnd)
-    {
-      fprintf (file, _("warning: corrupt unwind data\n"));
-      return;
-    }
-
   for (; i < ui->CountOfCodes; i++)
     {
       const bfd_byte *dta = ui->rawUnwindCodes + 2 * i;