From: Alan Modra <amodra@gmail.com>
Date: Sat, 10 May 2025 02:47:23 +0000 (+0930)
Subject: ubsan: size_inc_line_addr integer overflow
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=07cf922195d1e2eb1481da04048858b9d32928b6;p=thirdparty%2Fbinutils-gdb.git

ubsan: size_inc_line_addr integer overflow

Fix a fuzzer testcase where a large positive line_delta causes signed
overflow when subtracting -5.  Signed overflow is perfectly OK here.
---

diff --git a/gas/dwarf2dbg.c b/gas/dwarf2dbg.c
index 2963e52958a..955119bd87a 100644
--- a/gas/dwarf2dbg.c
+++ b/gas/dwarf2dbg.c
@@ -1632,7 +1632,7 @@ size_inc_line_addr (int line_delta, addressT addr_delta)
     }
 
   /* Bias the line delta by the base.  */
-  tmp = line_delta - DWARF2_LINE_BASE;
+  tmp = (unsigned) line_delta - DWARF2_LINE_BASE;
 
   /* If the line increment is out of range of a special opcode, we
      must encode it with DW_LNS_advance_line.  */