Add some anti-feline input protection by refusing to process

input of excessive length.

Make 'args' parameter to Xfuncs const char * and do the multiple
argument parsing in Xswap() and Xflag() on a local copy.

diff --git a/sbin/fdisk/cmd.c b/sbin/fdisk/cmd.c
index 60589e0..3ced91d 100644 (file)
--- a/sbin/fdisk/cmd.c
+++ b/sbin/fdisk/cmd.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: cmd.c,v 1.162 2022/07/10 17:46:03 krw Exp $   */
+/*     $OpenBSD: cmd.c,v 1.163 2022/07/10 20:34:31 krw Exp $   */
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -49,7 +49,7 @@ extern const unsigned char    manpage[];
 extern const int               manpage_sz;
 
 int
-Xreinit(char *args, struct mbr *mbr)
+Xreinit(const char *args, struct mbr *mbr)
 {
        int                     dogpt;
 
@@ -78,14 +78,20 @@ Xreinit(char *args, struct mbr *mbr)
 }
 
 int
-Xswap(char *args, struct mbr *mbr)
+Xswap(const char *args, struct mbr *mbr)
 {
+       char                     lbuf[LINEBUFSZ];
        char                    *from, *to;
        int                      pf, pt;
        struct prt               pp;
        struct gpt_partition     gg;
 
-       to = args;
+       if (strlcpy(lbuf, args, sizeof(lbuf)) >= sizeof(lbuf)) {
+               printf("argument string too long\n");
+               return CMD_CONT;
+       }
+
+       to = lbuf;
        from = strsep(&to, WHITESPACE);
 
        pt = parsepn(to);
@@ -223,7 +229,7 @@ edit(const int pn, struct mbr *mbr)
 }
 
 int
-Xedit(char *args, struct mbr *mbr)
+Xedit(const char *args, struct mbr *mbr)
 {
        struct gpt_partition     oldgg;
        struct prt               oldprt;
@@ -298,7 +304,7 @@ setpid(const int pn, struct mbr *mbr)
 }
 
 int
-Xsetpid(char *args, struct mbr *mbr)
+Xsetpid(const char *args, struct mbr *mbr)
 {
        struct gpt_partition    oldgg;
        struct prt              oldprt;
@@ -326,7 +332,7 @@ Xsetpid(char *args, struct mbr *mbr)
 }
 
 int
-Xselect(char *args, struct mbr *mbr)
+Xselect(const char *args, struct mbr *mbr)
 {
        static uint64_t         lba_firstembr = 0;
        uint64_t                lba_self;
@@ -361,7 +367,7 @@ Xselect(char *args, struct mbr *mbr)
 }
 
 int
-Xprint(char *args, struct mbr *mbr)
+Xprint(const char *args, struct mbr *mbr)
 {
        if (gh.gh_sig == GPTSIGNATURE)
                GPT_print(args, VERBOSE);
@@ -372,7 +378,7 @@ Xprint(char *args, struct mbr *mbr)
 }
 
 int
-Xwrite(char *args, struct mbr *mbr)
+Xwrite(const char *args, struct mbr *mbr)
 {
        int                     i, n;
 
@@ -404,25 +410,25 @@ Xwrite(char *args, struct mbr *mbr)
 }
 
 int
-Xquit(char *args, struct mbr *mbr)
+Xquit(const char *args, struct mbr *mbr)
 {
        return CMD_QUIT;
 }
 
 int
-Xabort(char *args, struct mbr *mbr)
+Xabort(const char *args, struct mbr *mbr)
 {
        exit(0);
 }
 
 int
-Xexit(char *args, struct mbr *mbr)
+Xexit(const char *args, struct mbr *mbr)
 {
        return CMD_EXIT;
 }
 
 int
-Xhelp(char *args, struct mbr *mbr)
+Xhelp(const char *args, struct mbr *mbr)
 {
        USER_help();
 
@@ -430,7 +436,7 @@ Xhelp(char *args, struct mbr *mbr)
 }
 
 int
-Xupdate(char *args, struct mbr *mbr)
+Xupdate(const char *args, struct mbr *mbr)
 {
        memcpy(mbr->mbr_code, default_dmbr.dmbr_boot, sizeof(mbr->mbr_code));
        mbr->mbr_signature = DOSMBR_SIGNATURE;
@@ -439,14 +445,20 @@ Xupdate(char *args, struct mbr *mbr)
 }
 
 int
-Xflag(char *args, struct mbr *mbr)
+Xflag(const char *args, struct mbr *mbr)
 {
+       char                     lbuf[LINEBUFSZ];
        const char              *errstr;
        char                    *part, *flag;
        long long                val = -1;
        int                      i, pn;
 
-       flag = args;
+       if (strlcpy(lbuf, args, sizeof(lbuf)) >= sizeof(lbuf)) {
+               printf("argument string too long\n");
+               return CMD_CONT;
+       }
+
+       flag = lbuf;
        part = strsep(&flag, WHITESPACE);
 
        pn = parsepn(part);
@@ -490,7 +502,7 @@ Xflag(char *args, struct mbr *mbr)
 }
 
 int
-Xmanual(char *args, struct mbr *mbr)
+Xmanual(const char *args, struct mbr *mbr)
 {
        char                    *pager = "/usr/bin/less";
        char                    *p;

diff --git a/sbin/fdisk/cmd.h b/sbin/fdisk/cmd.h
index aeda957..1a6b9f9 100644 (file)
--- a/sbin/fdisk/cmd.h
+++ b/sbin/fdisk/cmd.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: cmd.h,v 1.26 2021/10/25 13:51:25 krw Exp $    */
+/*     $OpenBSD: cmd.h,v 1.27 2022/07/10 20:34:31 krw Exp $    */
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -22,18 +22,18 @@
 #define CMD_CLEAN      0x0003
 #define CMD_DIRTY      0x0004
 
-int            Xreinit(char *, struct mbr *);
-int            Xdisk(char *, struct mbr *);
-int            Xmanual(char *, struct mbr *);
-int            Xedit(char *, struct mbr *);
-int            Xsetpid(char *, struct mbr *);
-int            Xselect(char *, struct mbr *);
-int            Xswap(char *, struct mbr *);
-int            Xprint(char *, struct mbr *);
-int            Xwrite(char *, struct mbr *);
-int            Xexit(char *, struct mbr *);
-int            Xquit(char *, struct mbr *);
-int            Xabort(char *, struct mbr *);
-int            Xhelp(char *, struct mbr *);
-int            Xflag(char *, struct mbr *);
-int            Xupdate(char *, struct mbr *);
+int            Xreinit(const char *, struct mbr *);
+int            Xdisk(const char *, struct mbr *);
+int            Xmanual(const char *, struct mbr *);
+int            Xedit(const char *, struct mbr *);
+int            Xsetpid(const char *, struct mbr *);
+int            Xselect(const char *, struct mbr *);
+int            Xswap(const char *, struct mbr *);
+int            Xprint(const char *, struct mbr *);
+int            Xwrite(const char *, struct mbr *);
+int            Xexit(const char *, struct mbr *);
+int            Xquit(const char *, struct mbr *);
+int            Xabort(const char *, struct mbr *);
+int            Xhelp(const char *, struct mbr *);
+int            Xflag(const char *, struct mbr *);
+int            Xupdate(const char *, struct mbr *);

diff --git a/sbin/fdisk/misc.c b/sbin/fdisk/misc.c
index 34019bf..72ce228 100644 (file)
--- a/sbin/fdisk/misc.c
+++ b/sbin/fdisk/misc.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: misc.c,v 1.87 2022/04/20 15:49:56 krw Exp $   */
+/*     $OpenBSD: misc.c,v 1.88 2022/07/10 20:34:31 krw Exp $   */
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -67,6 +67,7 @@ string_from_line(char *buf, const size_t buflen, const int trim)
        static char             *line;
        static size_t            sz;
        ssize_t                  len;
+       size_t                   n;
        unsigned int             i;
 
        len = getline(&line, &sz, stdin);
@@ -76,7 +77,7 @@ string_from_line(char *buf, const size_t buflen, const int trim)
        switch (trim) {
        case UNTRIMMED:
                line[strcspn(line, "\n")] = '\0';
-               strlcpy(buf, line, buflen);
+               n = strlcpy(buf, line, buflen);
                break;
        case TRIMMED:
                for (i = strlen(line); i > 0; i--) {
@@ -84,9 +85,14 @@ string_from_line(char *buf, const size_t buflen, const int trim)
                                break;
                        line[i - 1] = '\0';
                }
-               strlcpy(buf, line + strspn(line, WHITESPACE), buflen);
+               n = strlcpy(buf, line + strspn(line, WHITESPACE), buflen);
                break;
        }
+
+       if (n >= buflen) {
+               printf("input too long\n");
+               memset(buf, 0, buflen);
+       }
 }
 
 int

diff --git a/sbin/fdisk/user.c b/sbin/fdisk/user.c
index 69e2de4..7773443 100644 (file)
--- a/sbin/fdisk/user.c
+++ b/sbin/fdisk/user.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: user.c,v 1.81 2022/07/10 17:46:03 krw Exp $   */
+/*     $OpenBSD: user.c,v 1.82 2022/07/10 20:34:31 krw Exp $   */
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -34,7 +34,7 @@
 struct cmd {
        char    *cmd_name;
        int      cmd_gpt;
-       int     (*cmd_fcn)(char *, struct mbr *);
+       int     (*cmd_fcn)(const char *, struct mbr *);
        char    *cmd_help;
 };