[src/trunk]: src/sys Use gets_s instead of gets. The x86 bootloader prompt is...

[maxv <maxv%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/37c8fc8fcb41
branches:  trunk
changeset: 815855:37c8fc8fcb41
user:      maxv <maxv%NetBSD.org@localhost>
date:      Sun Jun 05 13:33:03 2016 +0000

description:
Use gets_s instead of gets. The x86 bootloader prompt is easy to
overflow.

diffstat:

 sys/arch/i386/stand/lib/bootmenu.c  |   4 +-
 sys/arch/i386/stand/lib/menuutils.c |   4 +-
 sys/lib/libsa/gets.c                |  60 ++++++++++++++++++++++++++++++++++++-
 sys/lib/libsa/stand.h               |   4 +-
 4 files changed, 66 insertions(+), 6 deletions(-)

diffs (132 lines):

diff -r d3b75cd5dbbd -r 37c8fc8fcb41 sys/arch/i386/stand/lib/bootmenu.c
--- a/sys/arch/i386/stand/lib/bootmenu.c        Sun Jun 05 11:01:39 2016 +0000
+++ b/sys/arch/i386/stand/lib/bootmenu.c        Sun Jun 05 13:33:03 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: bootmenu.c,v 1.14 2014/08/10 07:40:49 isaki Exp $      */
+/*     $NetBSD: bootmenu.c,v 1.15 2016/06/05 13:33:03 maxv Exp $       */
 
 /*-
  * Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -178,7 +178,7 @@
                                printf("\nOption: [%d]:",
                                    bootcfg_info.def + 1);
 
-                       gets(input);
+                       gets_s(input, sizeof(input));
                        choice = getchoicefrominput(input, bootcfg_info.def);
                } else if (bootcfg_info.timeout == 0)
                        choice = bootcfg_info.def;
diff -r d3b75cd5dbbd -r 37c8fc8fcb41 sys/arch/i386/stand/lib/menuutils.c
--- a/sys/arch/i386/stand/lib/menuutils.c       Sun Jun 05 11:01:39 2016 +0000
+++ b/sys/arch/i386/stand/lib/menuutils.c       Sun Jun 05 13:33:03 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: menuutils.c,v 1.4 2014/04/06 19:11:26 jakllsch Exp $   */
+/*     $NetBSD: menuutils.c,v 1.5 2016/06/05 13:33:03 maxv Exp $       */
 
 /*
  * Copyright (c) 1996, 1997
@@ -71,7 +71,7 @@
 
                input[0] = '\0';
                printf("> ");
-               gets(input);
+               gets_s(input, sizeof(input));
 
                /*
                 * Skip leading whitespace.
diff -r d3b75cd5dbbd -r 37c8fc8fcb41 sys/lib/libsa/gets.c
--- a/sys/lib/libsa/gets.c      Sun Jun 05 11:01:39 2016 +0000
+++ b/sys/lib/libsa/gets.c      Sun Jun 05 13:33:03 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: gets.c,v 1.10 2007/11/24 13:20:55 isaki Exp $  */
+/*     $NetBSD: gets.c,v 1.11 2016/06/05 13:33:03 maxv Exp $   */
 
 /*-
  * Copyright (c) 1993
@@ -85,3 +85,61 @@
        }
        /*NOTREACHED*/
 }
+
+void
+gets_s(char *buf, size_t size)
+{
+       int c;
+       char *lp;
+
+       for (lp = buf;;) {
+               if (lp - buf == size) {
+                       lp--;
+                       *lp = '\0';
+                       return;
+               }
+               switch (c = getchar() & 0177) {
+               case '\n':
+               case '\r':
+                       *lp = '\0';
+                       putchar('\n');
+                       return;
+               case '\b':
+               case '\177':
+                       if (lp > buf) {
+                               lp--;
+                               putchar('\b');
+                               putchar(' ');
+                               putchar('\b');
+                       }
+                       break;
+#if HASH_ERASE
+               case '#':
+                       if (lp > buf)
+                               --lp;
+                       break;
+#endif
+               case 'r' & 037: {
+                       char *p;
+
+                       putchar('\n');
+                       for (p = buf; p < lp; ++p)
+                               putchar(*p);
+                       break;
+               }
+#if AT_ERASE
+               case '@':
+#endif
+               case 'u' & 037:
+               case 'w' & 037:
+                       lp = buf;
+                       putchar('\n');
+                       break;
+               default:
+                       *lp++ = c;
+                       putchar(c);
+                       break;
+               }
+       }
+       /*NOTREACHED*/
+}
diff -r d3b75cd5dbbd -r 37c8fc8fcb41 sys/lib/libsa/stand.h
--- a/sys/lib/libsa/stand.h     Sun Jun 05 11:01:39 2016 +0000
+++ b/sys/lib/libsa/stand.h     Sun Jun 05 13:33:03 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: stand.h,v 1.79 2014/08/10 07:40:49 isaki Exp $ */
+/*     $NetBSD: stand.h,v 1.80 2016/06/05 13:33:03 maxv Exp $  */
 
 /*
  * Copyright (c) 1999 Christopher G. Demetriou.  All rights reserved.
@@ -78,6 +78,7 @@
 #ifdef LIBSA_RENAME_PRINTF
 #define getchar                libsa_getchar
 #define gets           libsa_gets
+#define gets_s         libsa_gets_s
 #define printf         libsa_printf
 #define putchar                libsa_putchar
 #define vprintf                libsa_vprintf
@@ -258,6 +259,7 @@
     __attribute__((__format__(__printf__, 3, 0)));
 void   twiddle(void);
 void   gets(char *);
+void   gets_s(char *, size_t);
 int    getfile(char *prompt, int mode);
 char   *strerror(int);
 __dead void    exit(int);