[binutils-gdb] kvx: asan: out-of-bounds read

[binutils-gdb] kvx: asan: out-of-bounds read

[Alan Modra]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=847fb383d83039b194f68d9e09974a3de4095eb5

commit 847fb383d83039b194f68d9e09974a3de4095eb5
Author: Alan Modra <amodra@gmail.com>
Date:   Wed Aug 23 08:18:39 2023 +0930

    kvx: asan: out-of-bounds read
    
    kvx-parse.c:parse_with_restarts does
      if (!tok.insn[tok.begin])
        tok.class_id = -3;
    then a little later
      printf_debug (1, "\nEntering rule: %d (Trying to match: (%s)[%d])\n", jump_target,
                    TOKEN_NAME (CLASS_ID (tok)), CLASS_ID (tok));
    
    This results in a buffer overrun in TOKEN_NAME.  Fix that.
    
            * config/tc-kvx.h (TOKEN_NAME): Check for tok <= 0, not just -1.

Diff:
---
 gas/config/tc-kvx.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/gas/config/tc-kvx.h b/gas/config/tc-kvx.h
index 11787bf0532..85344cbe179 100644
--- a/gas/config/tc-kvx.h
+++ b/gas/config/tc-kvx.h
@@ -37,7 +37,8 @@
 #define KVX_RA_REGNO (67)
 #define KVX_SP_REGNO (12)
 
-#define TOKEN_NAME(tok) ((tok) == -1 ? "unknown token" : env.tokens_names[(tok) - 1])
+#define TOKEN_NAME(tok) \
+  ((tok) <= 0 ? "unknown token" : env.tokens_names[(tok) - 1])
 
 struct token_s {
   char *insn;