2007-10-24 16:44:49

by Adrian Bunk

[permalink] [raw]
Subject: gfs2_fh_to_parent() array overflow

The Coverity checker spotted the following array overflow caused by
commit 34c0d154243dd913c5690ae6ceb9557017429b9c:


include/linux/exportfs.h contains:

<-- snip -->

...
struct fid {
...
__u32 raw[6];
};
};

<-- snip -->


fs/gfs2/ops_export.c contains:

<-- snip -->

...
static struct dentry *gfs2_fh_to_parent(struct super_block *sb, struct fid *fid,
int fh_len, int fh_type)
{
struct gfs2_inum_host parent;
__be32 *fh = (__force __be32 *)fid->raw; <------------

switch (fh_type) {
case GFS2_LARGE_FH_SIZE:
case GFS2_OLD_FH_SIZE:
parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32;
parent.no_formal_ino |= be32_to_cpu(fh[5]);
parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32;
^^^^^
parent.no_addr |= be32_to_cpu(fh[7]);
... ^^^^^

<-- snip -->


cu
Adrian

--

"Is there not promise of rain?" Ling Tan asked suddenly out
of the darkness. There had been need of rain for many days.
"Only a promise," Lao Er said.
Pearl S. Buck - Dragon Seed


2007-10-27 21:01:18

by Christoph Hellwig

[permalink] [raw]
Subject: Re: gfs2_fh_to_parent() array overflow

On Wed, Oct 24, 2007 at 06:26:26PM +0200, Adrian Bunk wrote:
> The Coverity checker spotted the following array overflow caused by
> commit 34c0d154243dd913c5690ae6ceb9557017429b9c:

The line is a left-over from times when gfs stored the mode of the
inode in the file handle. It can simply be deleted. Steve, do you
want a patch for that or could you commit that one-liner directly?

> fs/gfs2/ops_export.c contains:
>
> <-- snip -->
>
> ...
> static struct dentry *gfs2_fh_to_parent(struct super_block *sb, struct fid *fid,
> int fh_len, int fh_type)
> {
> struct gfs2_inum_host parent;
> __be32 *fh = (__force __be32 *)fid->raw; <------------
>
> switch (fh_type) {
> case GFS2_LARGE_FH_SIZE:
> case GFS2_OLD_FH_SIZE:
> parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32;
> parent.no_formal_ino |= be32_to_cpu(fh[5]);
> parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32;
> ^^^^^
> parent.no_addr |= be32_to_cpu(fh[7]);
> ... ^^^^^
>
> <-- snip -->
>
>
> cu
> Adrian
>
> --
>
> "Is there not promise of rain?" Ling Tan asked suddenly out
> of the darkness. There had been need of rain for many days.
> "Only a promise," Lao Er said.
> Pearl S. Buck - Dragon Seed
---end quoted text---

2007-10-29 09:18:00

by Steven Whitehouse

[permalink] [raw]
Subject: Re: gfs2_fh_to_parent() array overflow

Hi,

On Sat, 2007-10-27 at 23:00 +0200, Christoph Hellwig wrote:
> On Wed, Oct 24, 2007 at 06:26:26PM +0200, Adrian Bunk wrote:
> > The Coverity checker spotted the following array overflow caused by
> > commit 34c0d154243dd913c5690ae6ceb9557017429b9c:
>
> The line is a left-over from times when gfs stored the mode of the
> inode in the file handle. It can simply be deleted. Steve, do you
> want a patch for that or could you commit that one-liner directly?
>

I'm just back from holiday this morning and this is looking a bit more
complicated than that... give me a day or two and I'll try and come up
with a solution,

Steve.

> > fs/gfs2/ops_export.c contains:
> >
> > <-- snip -->
> >
> > ...
> > static struct dentry *gfs2_fh_to_parent(struct super_block *sb, struct fid *fid,
> > int fh_len, int fh_type)
> > {
> > struct gfs2_inum_host parent;
> > __be32 *fh = (__force __be32 *)fid->raw; <------------
> >
> > switch (fh_type) {
> > case GFS2_LARGE_FH_SIZE:
> > case GFS2_OLD_FH_SIZE:
> > parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32;
> > parent.no_formal_ino |= be32_to_cpu(fh[5]);
> > parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32;
> > ^^^^^
> > parent.no_addr |= be32_to_cpu(fh[7]);
> > ... ^^^^^
> >
> > <-- snip -->
> >
> >
> > cu
> > Adrian
> >
> > --
> >
> > "Is there not promise of rain?" Ling Tan asked suddenly out
> > of the darkness. There had been need of rain for many days.
> > "Only a promise," Lao Er said.
> > Pearl S. Buck - Dragon Seed
> ---end quoted text---

2008-02-13 21:50:45

by Adrian Bunk

[permalink] [raw]
Subject: Re: gfs2_fh_to_parent() array overflow

On Mon, Oct 29, 2007 at 09:11:21AM +0000, Steven Whitehouse wrote:
> Hi,
>
> On Sat, 2007-10-27 at 23:00 +0200, Christoph Hellwig wrote:
> > On Wed, Oct 24, 2007 at 06:26:26PM +0200, Adrian Bunk wrote:
> > > The Coverity checker spotted the following array overflow caused by
> > > commit 34c0d154243dd913c5690ae6ceb9557017429b9c:
> >
> > The line is a left-over from times when gfs stored the mode of the
> > inode in the file handle. It can simply be deleted. Steve, do you
> > want a patch for that or could you commit that one-liner directly?
> >
>
> I'm just back from holiday this morning and this is looking a bit more
> complicated than that... give me a day or two and I'll try and come up
> with a solution,

This issue is still present in 2.6.25-rc1.

> Steve.
>
> > > fs/gfs2/ops_export.c contains:
> > >
> > > <-- snip -->
> > >
> > > ...
> > > static struct dentry *gfs2_fh_to_parent(struct super_block *sb, struct fid *fid,
> > > int fh_len, int fh_type)
> > > {
> > > struct gfs2_inum_host parent;
> > > __be32 *fh = (__force __be32 *)fid->raw; <------------
> > >
> > > switch (fh_type) {
> > > case GFS2_LARGE_FH_SIZE:
> > > case GFS2_OLD_FH_SIZE:
> > > parent.no_formal_ino = ((u64)be32_to_cpu(fh[4])) << 32;
> > > parent.no_formal_ino |= be32_to_cpu(fh[5]);
> > > parent.no_addr = ((u64)be32_to_cpu(fh[6])) << 32;
> > > ^^^^^
> > > parent.no_addr |= be32_to_cpu(fh[7]);
> > > ... ^^^^^
> > >
> > > <-- snip -->
> > >
> > >
> > > cu
> > > Adrian
> > >

cu
Adrian

--

"Is there not promise of rain?" Ling Tan asked suddenly out
of the darkness. There had been need of rain for many days.
"Only a promise," Lao Er said.
Pearl S. Buck - Dragon Seed

2008-02-14 10:53:56

by Steven Whitehouse

[permalink] [raw]
Subject: Re: gfs2_fh_to_parent() array overflow

Hi,

On Wed, 2008-02-13 at 23:31 +0200, Adrian Bunk wrote:
> On Mon, Oct 29, 2007 at 09:11:21AM +0000, Steven Whitehouse wrote:
> > Hi,
> >
> > On Sat, 2007-10-27 at 23:00 +0200, Christoph Hellwig wrote:
> > > On Wed, Oct 24, 2007 at 06:26:26PM +0200, Adrian Bunk wrote:
> > > > The Coverity checker spotted the following array overflow caused by
> > > > commit 34c0d154243dd913c5690ae6ceb9557017429b9c:
> > >
> > > The line is a left-over from times when gfs stored the mode of the
> > > inode in the file handle. It can simply be deleted. Steve, do you
> > > want a patch for that or could you commit that one-liner directly?
> > >
> >
> > I'm just back from holiday this morning and this is looking a bit more
> > complicated than that... give me a day or two and I'll try and come up
> > with a solution,
>
> This issue is still present in 2.6.25-rc1.
>
Yes, it seems to have slipped off my list somehow... I've opened a bz
(#432775 at bugzilla.redhat.com) to ensure that it doesn't get missed
again,

Steve.