2013-03-14 15:19:48

by Wei Yongjun

Subject: [PATCH] cciss: fix invalid use of sizeof in cciss_find_cfgtables()

From: Wei Yongjun <[email protected]>

sizeof() when applied to a pointer typed expression gives the
size of the pointer, not that of the pointed data.

Signed-off-by: Wei Yongjun <[email protected]>
---
drivers/block/cciss.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index ade58bc..1c1b8e5 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -4206,7 +4206,7 @@ static int cciss_find_cfgtables(ctlr_info_t *h)
if (rc)
return rc;
h->cfgtable = remap_pci_mem(pci_resource_start(h->pdev,
- cfg_base_addr_index) + cfg_offset, sizeof(h->cfgtable));
+ cfg_base_addr_index) + cfg_offset, sizeof(*h->cfgtable));
if (!h->cfgtable)
return -ENOMEM;
rc = write_driver_ver_to_cfgtable(h->cfgtable);

2013-03-14 15:31:48

by Stephen M. Cameron

Subject: Re: [PATCH] cciss: fix invalid use of sizeof in cciss_find_cfgtables()

On Thu, Mar 14, 2013 at 11:19:45PM +0800, Wei Yongjun wrote:
> From: Wei Yongjun <[email protected]>
>
> sizeof() when applied to a pointer typed expression gives the
> size of the pointer, not that of the pointed data.
>
> Signed-off-by: Wei Yongjun <[email protected]>
> ---
> drivers/block/cciss.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
> index ade58bc..1c1b8e5 100644
> --- a/drivers/block/cciss.c
> +++ b/drivers/block/cciss.c
> @@ -4206,7 +4206,7 @@ static int cciss_find_cfgtables(ctlr_info_t *h)
> if (rc)
> return rc;
> h->cfgtable = remap_pci_mem(pci_resource_start(h->pdev,
> - cfg_base_addr_index) + cfg_offset, sizeof(h->cfgtable));
> + cfg_base_addr_index) + cfg_offset, sizeof(*h->cfgtable));
> if (!h->cfgtable)
> return -ENOMEM;
> rc = write_driver_ver_to_cfgtable(h->cfgtable);
>

Ack.

I suppose it has worked all this time because ioremap can't map less
than a page, and sizeof(*h->cfgtable) is less than a page, and likely
starts on a page boundary.

-- steve

2013-03-22 15:11:25

by Jens Axboe

Subject: Re: [PATCH] cciss: fix invalid use of sizeof in cciss_find_cfgtables()

On Thu, Mar 14 2013, [email protected] wrote:
> On Thu, Mar 14, 2013 at 11:19:45PM +0800, Wei Yongjun wrote:
> > From: Wei Yongjun <[email protected]>
> >
> > sizeof() when applied to a pointer typed expression gives the
> > size of the pointer, not that of the pointed data.
> >
> > Signed-off-by: Wei Yongjun <[email protected]>
> > ---
> > drivers/block/cciss.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
> > index ade58bc..1c1b8e5 100644
> > --- a/drivers/block/cciss.c
> > +++ b/drivers/block/cciss.c
> > @@ -4206,7 +4206,7 @@ static int cciss_find_cfgtables(ctlr_info_t *h)
> > if (rc)
> > return rc;
> > h->cfgtable = remap_pci_mem(pci_resource_start(h->pdev,
> > - cfg_base_addr_index) + cfg_offset, sizeof(h->cfgtable));
> > + cfg_base_addr_index) + cfg_offset, sizeof(*h->cfgtable));
> > if (!h->cfgtable)
> > return -ENOMEM;
> > rc = write_driver_ver_to_cfgtable(h->cfgtable);
> >
>
> Ack.
>
> I suppose it has worked all this time because ioremap can't map less
> than a page, and sizeof(*h->cfgtable) is less than a page, and likely
> starts on a page boundary.

Queued up for 3.9, thanks.

--
Jens Axboe