From: semarie <semarie@openbsd.org>
Date: Tue, 23 Jun 2015 15:16:34 +0000 (+0000)
Subject: This patch ensure that when an error is detected, the freed variables in
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=c4fd534d3100e8f033b107fc7ca7ca3fcaf3ed0f;p=openbsd

This patch ensure that when an error is detected, the freed variables in
elf_symloadx() are reinitialised.

Else show_file() in nm.c will used these variables, even if they has
just been freed. (nm.c +689).

Problem found by afl.

ok miod@
---

diff --git a/usr.bin/nm/elf.c b/usr.bin/nm/elf.c
index bf134ad7513..c44a6babbe5 100644
--- a/usr.bin/nm/elf.c
+++ b/usr.bin/nm/elf.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: elf.c,v 1.31 2015/06/23 15:13:29 semarie Exp $	*/
+/*	$OpenBSD: elf.c,v 1.32 2015/06/23 15:16:34 semarie Exp $	*/
 
 /*
  * Copyright (c) 2003 Michael Shalayeff
@@ -498,6 +498,7 @@ elf_symloadx(const char *name, FILE *fp, off_t foff, Elf_Ehdr *eh,
 				warn("%s: malloc names", name);
 				if (stab)
 					MUNMAP(stab, *pstabsize);
+				*pnrawnames = 0;
 				return (1);
 			}
 			if ((*psnames = calloc(*pnrawnames, sizeof(np))) == NULL) {
@@ -505,6 +506,8 @@ elf_symloadx(const char *name, FILE *fp, off_t foff, Elf_Ehdr *eh,
 				if (stab)
 					MUNMAP(stab, *pstabsize);
 				free(*pnames);
+				*pnames = NULL;
+				*pnrawnames = 0;
 				return (1);
 			}
 
@@ -516,6 +519,9 @@ elf_symloadx(const char *name, FILE *fp, off_t foff, Elf_Ehdr *eh,
 						MUNMAP(stab, *pstabsize);
 					free(*pnames);
 					free(*psnames);
+					*pnames = NULL;
+					*psnames = NULL;
+					*pnrawnames = 0;
 					return (1);
 				}
 
diff --git a/usr.bin/nm/util.h b/usr.bin/nm/util.h
index 8e5553ead86..622f2158972 100644
--- a/usr.bin/nm/util.h
+++ b/usr.bin/nm/util.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: util.h,v 1.3 2015/05/17 20:19:08 guenther Exp $	*/
+/*	$OpenBSD: util.h,v 1.4 2015/06/23 15:16:34 semarie Exp $	*/
 
 /*
  * Placed in the public domain by Todd C. Miller <Todd.Miller@courtesan.com>
@@ -26,6 +26,7 @@
 		munmap(addr, len);					\
 	else								\
 		free(addr);						\
+	addr = NULL;							\
 } while (0)
 
 extern int usemmap;