From: Alan Modra <amodra@gmail.com>
Date: Thu, 25 Jan 2024 22:44:13 +0000 (+1030)
Subject: Assertion failure dumping .eh_frame_hdr
X-Git-Tag: gdb-15-branchpoint~1142
X-Git-Url: http://git.ipfire.org/gitweb/gitweb.cgi?a=commitdiff_plain;h=e14f7abaf81d5d0aa7898570024286de8c188817;p=thirdparty%2Fbinutils-gdb.git

Assertion failure dumping .eh_frame_hdr

dwarf.c can hit "Assertion '(start) <= (end)' failed" on truncated
sections, due to get_encoded_eh_value wrongly returning a full count
for truncated words.

	* dwarf.c (get_encoded_eh_value): Return zero for truncated words.
---

diff --git a/binutils/dwarf.c b/binutils/dwarf.c
index a30bc1cb9ab..1947ab180ee 100644
--- a/binutils/dwarf.c
+++ b/binutils/dwarf.c
@@ -9236,37 +9236,37 @@ get_encoded_eh_value (unsigned int     encoding,
     case DW_EH_PE_udata2:
       old_start = start;
       SAFE_BYTE_GET_AND_INC (val, start, 2, end);
-      len = (start == old_start) ? 0 : 2;
+      len = start - old_start == 2 ? 2 : 0;
       break;
 
     case DW_EH_PE_udata4:
       old_start = start;
       SAFE_BYTE_GET_AND_INC (val, start, 4, end);
-      len = (start == old_start) ? 0 : 4;
+      len = start - old_start == 4 ? 4 : 0;
       break;
 
     case DW_EH_PE_udata8:
       old_start = start;
       SAFE_BYTE_GET_AND_INC (val, start, 8, end);
-      len = (start == old_start) ? 0 : 8;
+      len = start - old_start == 8 ? 8 : 0;
       break;
 
     case DW_EH_PE_sdata2:
       old_start = start;
       SAFE_SIGNED_BYTE_GET_AND_INC (val, start, 2, end);
-      len = (start == old_start) ? 0 : 2;
+      len = start - old_start == 2 ? 2 : 0;
       break;
 
     case DW_EH_PE_sdata4:
       old_start = start;
       SAFE_SIGNED_BYTE_GET_AND_INC (val, start, 4, end);
-      len = (start == old_start) ? 0 : 4;
+      len = start - old_start == 4 ? 4 : 0;
       break;
 
     case DW_EH_PE_sdata8:
       old_start = start;
       SAFE_SIGNED_BYTE_GET_AND_INC (val, start, 8, end);
-      len = (start == old_start) ? 0 : 8;
+      len = start - old_start == 8 ? 8 : 0;
       break;
 
     default: