[PATCH] fix sun partition overflow over 1T

[PATCH] fix sun partition overflow over 1T

[Eric Sandeen]

Although sun partition labels aren't supposed to support > 1T, apparently
linux partition editors will allow up to 2T.  This can cause problems
in the kernel when these larger partitions are read, due to a signed
int container.

num_sectors in the sun_disklabel struct is marked as __u32 in 2.4, and 
as __be32 in 2.6.  However, this is assigned to a signed int in
sun_partition():

                int num_sectors;

                st_sector = be32_to_cpu(p->start_cylinder) * spc;
                num_sectors = be32_to_cpu(p->num_sectors);

Changing num_sectors to an unsigned int avoids this problem.

Thanks,

-Eric

Signed-off-by: Eric Sandeen <esandeen@redhat.com>

Index: linux-2.6.17/fs/partitions/sun.c
===================================================================
--- linux-2.6.17.orig/fs/partitions/sun.c
+++ linux-2.6.17/fs/partitions/sun.c
@@ -74,7 +74,7 @@ int sun_partition(struct parsed_partitio
 	spc = be16_to_cpu(label->ntrks) * be16_to_cpu(label->nsect);
 	for (i = 0; i < 8; i++, p++) {
 		unsigned long st_sector;
-		int num_sectors;
+		unsigned int num_sectors;
 
 		st_sector = be32_to_cpu(p->start_cylinder) * spc;
 		num_sectors = be32_to_cpu(p->num_sectors);

Re: [PATCH] fix sun partition overflow over 1T

[Alan Cox]

Ar Gwe, 2006-08-04 am 11:22 -0500, ysgrifennodd Eric Sandeen:
> Although sun partition labels aren't supposed to support > 1T, apparently
> linux partition editors will allow up to 2T.  This can cause problems
> in the kernel when these larger partitions are read, due to a signed
> int container.
> 
> num_sectors in the sun_disklabel struct is marked as __u32 in 2.4, and 
> as __be32 in 2.6.  However, this is assigned to a signed int in
> sun_partition():
> 
>                 int num_sectors;
> 
>                 st_sector = be32_to_cpu(p->start_cylinder) * spc;
>                 num_sectors = be32_to_cpu(p->num_sectors);
> 
> Changing num_sectors to an unsigned int avoids this problem.
> 

> Signed-off-by: Eric Sandeen <esandeen@redhat.com>

Acked-by: Alan Cox <alan@redhat.com>

Re: [PATCH] fix sun partition overflow over 1T

[David Miller]

From: Alan Cox <alan@lxorguk.ukuu.org.uk>
Date: Fri, 04 Aug 2006 17:56:30 +0100

> Ar Gwe, 2006-08-04 am 11:22 -0500, ysgrifennodd Eric Sandeen:
> > Although sun partition labels aren't supposed to support > 1T, apparently
> > linux partition editors will allow up to 2T.  This can cause problems
> > in the kernel when these larger partitions are read, due to a signed
> > int container.
> > 
> > num_sectors in the sun_disklabel struct is marked as __u32 in 2.4, and 
> > as __be32 in 2.6.  However, this is assigned to a signed int in
> > sun_partition():
> > 
> >                 int num_sectors;
> > 
> >                 st_sector = be32_to_cpu(p->start_cylinder) * spc;
> >                 num_sectors = be32_to_cpu(p->num_sectors);
> > 
> > Changing num_sectors to an unsigned int avoids this problem.
> > 
> 
> > Signed-off-by: Eric Sandeen <esandeen@redhat.com>
> 
> Acked-by: Alan Cox <alan@redhat.com>

Applied, thanks a lot.