Synopsis: disklabel 'b' suffix not working when adding partition
with editor
Category: i386
Environment:
System : OpenBSD 5.0
Details : OpenBSD 5.0 (GENERIC) #43: Wed Aug 17 10:10:52
MDT 2011
[email protected]:/usr/src/sys/arch/i386/compile/GENERIC
Architecture: OpenBSD.i386
Machine : i386
Description:
Adding a new patition from the disklabel interactive editor,
and specifying the partition size in bytes, by appending a 'b' suffix to
the size, always leads to a error. The error message says:
"The size can't be more than 2048 sectors, or the partition
would
extend beyond the last sector (2048) of the OpenBSD portion of
the disk. The 'b' command can change this limit."
Where 2048 is my test disk size. This even happens when
requesting a partition of 1 byte big.
How-To-Repeat:
# disklabel -E vnd0
> d *
> a a
\n
1b
Fix:
This issue is caused by trying to make a 32-bit unsigned
integer negative, before storing it in a 64-bit signed integer. This
leads to the value being ULONG_MAX-value, insteald of -value.
The following patch fixes this issue, by first making the
unsigned integer signed:
--- sbin/disklabel/editor.c.orig Thu Dec 1 14:55:44 2011
+++ sbin/disklabel/editor.c Thu Dec 1 16:33:16 2011
@@ -1178,12 +1178,12 @@ getuint(struct disklabel *lp, char *prompt,
char *help
buf[--n] = '\0';
break;
case 'b':
- mult = -lp->d_secsize;
+ mult = -((int64_t)
lp->d_secsize);
buf[--n] = '\0';
break;
case 'k':
if (lp->d_secsize > 1024)
- mult = -lp->d_secsize /
1024LL;
+ mult = -((int64_t)
lp->d_secsize) / 1024LL;
else
mult = 1024LL /
lp->d_secsize;
buf[--n] = '\0';
