zalloc_malloc:Free hexdump preceeding buffer when we detect overflow

Move hexdump from stand/common/misc.c to stand/libsa/hexdump.c
(svn cp)
Disable use of pager - causes linking issue for boot1
can be re-enabled by defining HEXDUMP_PAGER.

Reviewed by:	stevek, imp
MFC after:	1 week
Sponsored by:	Juniper Networks
Differential Revision: https://reviews.freebsd.org/D26235

stand/common/bootstrap.h

@@ -68,7 +68,6 @@ int	getrootmount(char *rootdev);
 
 /* misc.c */
 char	*unargv(int argc, char *argv[]);
-void	hexdump(caddr_t region, size_t len);
 size_t	strlenout(vm_offset_t str);
 char	*strdupout(vm_offset_t str);
 void	kern_bzero(vm_offset_t dest, size_t len);

stand/common/misc.c

@@ -169,46 +169,6 @@ alloc_pread(readin_handle_t fd, off_t off, size_t len)
 	return (buf);
 }
 
-/*
- * Display a region in traditional hexdump format.
- */
-void
-hexdump(caddr_t region, size_t len)
-{
-    caddr_t	line;
-    int		x, c;
-    char	lbuf[80];
-#define emit(fmt, args...)	{sprintf(lbuf, fmt , ## args); pager_output(lbuf);}
-
-    pager_open();
-    for (line = region; line < (region + len); line += 16) {
-	emit("%08lx  ", (long) line);
-	
-	for (x = 0; x < 16; x++) {
-	    if ((line + x) < (region + len)) {
-		emit("%02x ", *(uint8_t *)(line + x));
-	    } else {
-		emit("-- ");
-	    }
-	    if (x == 7)
-		emit(" ");
-	}
-	emit(" |");
-	for (x = 0; x < 16; x++) {
-	    if ((line + x) < (region + len)) {
-		c = *(uint8_t *)(line + x);
-		if ((c < ' ') || (c > '~'))	/* !isprint(c) */
-		    c = '.';
-		emit("%c", c);
-	    } else {
-		emit(" ");
-	    }
-	}
-	emit("|\n");
-    }
-    pager_close();
-}
-
 void
 dev_cleanup(void)
 {

stand/libsa/Makefile

@@ -13,8 +13,9 @@ LIBSA_CPUARCH?=${MACHINE_CPUARCH}
 LIB?=		sa
 
 # standalone components and stuff we have modified locally
-SRCS+=	gzguts.h zutil.h __main.c abort.c assert.c bcd.c environment.c getopt.c gets.c \
-	globals.c pager.c panic.c printf.c strdup.c strerror.c \
+SRCS+=	gzguts.h zutil.h __main.c abort.c assert.c bcd.c environment.c \
+	getopt.c gets.c globals.c \
+	hexdump.c pager.c panic.c printf.c strdup.c strerror.c \
 	random.c sbrk.c twiddle.c zalloc.c zalloc_malloc.c
 
 # private (pruned) versions of libc string functions

stand/libsa/hexdump.c

@@ -0,0 +1,79 @@
+/*-
+ * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <string.h>
+#include <stand.h>
+
+/*
+ * Display a region in traditional hexdump format.
+ */
+void
+hexdump(caddr_t region, size_t len)
+{
+    caddr_t	line;
+    int		x, c;
+#ifdef HEXDUMP_PAGER
+    /* pager causes linking issues for some apps */
+#define emit(fmt, args...)	{sprintf(lbuf, fmt , ## args); pager_output(lbuf);}
+    char	lbuf[80];
+
+    pager_open();
+#else
+#define emit(fmt, args...) printf(fmt, ## args)
+#endif
+
+    for (line = region; line < (region + len); line += 16) {
+	emit("%08lx  ", (long) line);
+	
+	for (x = 0; x < 16; x++) {
+	    if ((line + x) < (region + len)) {
+		emit("%02x ", *(uint8_t *)(line + x));
+	    } else {
+		emit("-- ");
+	    }
+	    if (x == 7)
+		emit(" ");
+	}
+	emit(" |");
+	for (x = 0; x < 16; x++) {
+	    if ((line + x) < (region + len)) {
+		c = *(uint8_t *)(line + x);
+		if ((c < ' ') || (c > '~'))	/* !isprint(c) */
+		    c = '.';
+		emit("%c", c);
+	    } else {
+		emit(" ");
+	    }
+	}
+	emit("|\n");
+    }
+#ifdef HEXDUMP_PAGER
+    pager_close();
+#endif
+}

stand/libsa/pkgfs.c

@@ -60,7 +60,7 @@ struct fs_ops pkgfs_fsops = {
 };
 
 #define PKG_BUFSIZE	512
-#define	PKG_MAXCACHESZ	(16384 * 3)
+#define	PKG_MAXCACHESZ	(512 * 1024)
 
 #define	PKG_FILEEXT	".tgz"
 

stand/libsa/stand.h

@@ -470,4 +470,7 @@ extern void *reallocf(void *, size_t);
  */
 caddr_t ptov(uintptr_t);
 
+/* hexdump.c */
+void	hexdump(caddr_t region, size_t len);
+
 #endif	/* STAND_H */

stand/libsa/zalloc_malloc.c

@@ -52,6 +52,10 @@ void mallocstats(void);
 
 static void *Malloc_align(size_t, size_t);
 
+#ifndef MIN
+# define MIN(a,b) ((a) <= (b)) ? (a) : (b)
+#endif
+
 void *
 Malloc(size_t bytes, const char *file __unused, int line __unused)
 {
@@ -119,9 +123,14 @@ Free(void *ptr, const char *file, int line)
 			    ptr, file, line);
 			return;
 		}
-		if (res->ga_Magic != GAMAGIC)
+		if (res->ga_Magic != GAMAGIC) {
+			size_t dump_bytes;
+
+			dump_bytes = MIN((ptr - MallocPool.mp_Base), 512);
+			hexdump(ptr - dump_bytes, dump_bytes);
 			panic("free: guard1 fail @ %p from %s:%d",
 			    ptr, file, line);
+		}
 		res->ga_Magic = GAFREE;
 #endif
 #ifdef USEENDGUARD