The MBR uses a 32-bit unsigned integer to store the size of a slice, but

fdisk(1) internally uses a signed int.  Should a user attempt to specify
a slice containing more than 2^31 - 1 sectors, an error will be reported
on systems with sizeof(long) == 4 and the slice size will be silently
truncated on systems with sizeof(long) > 4.

Instead use an unsigned long to store the slice size in fdisk(1).  This
allows the user to specify a slice size up to the maximum permitted by
the MBR on-disk format and does not have any problems with silent
truncation should the use specify an slice size larger than 2^32 on systems
with sizeof(long) > 4.

Submitted by:	Mark Johnston (markjdb AT gmail DOT com)
MFC after:	2 weeks

1 files changed, 4 insertions, 4 deletions

diff --git a/sbin/fdisk/fdisk.c b/sbin/fdisk/fdisk.c
index 8314906..eb81e3b 100644
--- a/sbin/fdisk/fdisk.c
+++ b/sbin/fdisk/fdisk.c
@@ -108,9 +108,9 @@ typedef struct cmd {
     char		cmd;
     int			n_args;
     struct arg {
-	char	argtype;
-	int	arg_val;
-	char	*arg_str;
+	char		argtype;
+	unsigned long	arg_val;
+	char *		arg_str;
     }			args[MAX_ARGS];
 } CMD;
 
@@ -990,7 +990,7 @@ parse_config_line(char *line, CMD *command)
 	    if (isalpha(*cp))
 		command->args[command->n_args].argtype = *cp++;
 	    end = NULL;
-	    command->args[command->n_args].arg_val = strtol(cp, &end, 0);
+	    command->args[command->n_args].arg_val = strtoul(cp, &end, 0);
  	    if (cp == end || (!isspace(*end) && *end != '\0')) {
  		char ch;
  		end = cp;