[PATCH 00/26] use array_size

[PATCH 00/26] use array_size

[Julia Lawall]

Use array_size to protect against multiplication overflows.

This follows up on the following patches by Kees Cook from 2018.

42bc47b35320 ("treewide: Use array_size() in vmalloc()")
fad953ce0b22 ("treewide: Use array_size() in vzalloc()")

The changes were done using the following Coccinelle semantic patch,
adapted from the one posted by Kees.

// Drop single-byte sizes and redundant parens.
@@
    expression COUNT;
    typedef u8;
    typedef __u8;
    type t = {u8,__u8,char,unsigned char};
    identifier alloc = {vmalloc,vzalloc};
@@
      alloc(
-           (sizeof(t)) * (COUNT)
+           COUNT
      , ...)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
    expression COUNT;
    size_t e1, e2, e3;
    identifier alloc = {vmalloc,vzalloc};
@@

(    
      alloc(
-           (e1) * (e2) * (e3)
+           array3_size(e1, e2, e3)
      ,...)
|
      alloc(
-           (e1) * (e2) * (COUNT)
+           array3_size(COUNT, e1, e2)
      ,...)
)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
    expression STRIDE, COUNT;
    size_t e;
    identifier alloc = {vmalloc,vzalloc};
@@

      alloc(
-           (e) * (COUNT) * (STRIDE)
+           array3_size(COUNT, STRIDE, e)
      ,...)

// Any remaining multi-factor products, first at least 3-factor products
// when they're not all constants...
@@
    expression E1, E2, E3;
    constant C1, C2, C3;
    identifier alloc = {vmalloc,vzalloc};
@@
    
(
      alloc(C1 * C2 * C3,...)
|
      alloc(
-           (E1) * (E2) * (E3)
+           array3_size(E1, E2, E3)
      ,...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
    size_t e1,e2;
    expression COUNT;
    identifier alloc = {vmalloc,vzalloc};
@@

(
      alloc(
-           (e1) * (e2)
+           array_size(e1, e2)
      ,...)
|
      alloc(
-           (e1) * (COUNT)
+           array_size(COUNT, e1)
      ,...)
)
    
// And then all remaining 2 factors products when they're not all constants.
@@
    expression E1, E2;
    constant C1, C2;
    identifier alloc = {vmalloc,vzalloc};
@@
    
(
      alloc(C1 * C2,...)
|
      alloc(
-           (E1) * (E2)
+           array_size(E1, E2)
      ,...)
)


---

 arch/x86/kernel/cpu/sgx/main.c                    |    3 ++-
 drivers/accel/habanalabs/common/device.c          |    3 ++-
 drivers/accel/habanalabs/common/state_dump.c      |    6 +++---
 drivers/bus/mhi/host/init.c                       |    4 ++--
 drivers/comedi/comedi_buf.c                       |    4 ++--
 drivers/dma-buf/heaps/system_heap.c               |    2 +-
 drivers/gpu/drm/gud/gud_pipe.c                    |    2 +-
 drivers/gpu/drm/i915/gvt/gtt.c                    |    6 ++++--
 drivers/gpu/drm/vmwgfx/vmwgfx_devcaps.c           |    2 +-
 drivers/infiniband/hw/bnxt_re/qplib_res.c         |    4 ++--
 drivers/infiniband/hw/erdma/erdma_verbs.c         |    4 ++--
 drivers/infiniband/sw/siw/siw_qp.c                |    4 ++--
 drivers/infiniband/sw/siw/siw_verbs.c             |    6 +++---
 drivers/iommu/tegra-gart.c                        |    4 ++--
 drivers/net/ethernet/amd/pds_core/core.c          |    4 ++--
 drivers/net/ethernet/freescale/enetc/enetc.c      |    4 ++--
 drivers/net/ethernet/google/gve/gve_tx.c          |    2 +-
 drivers/net/ethernet/marvell/octeon_ep/octep_rx.c |    2 +-
 drivers/net/ethernet/microsoft/mana/hw_channel.c  |    2 +-
 drivers/net/ethernet/pensando/ionic/ionic_lif.c   |    4 ++--
 drivers/scsi/fnic/fnic_trace.c                    |    2 +-
 drivers/scsi/qla2xxx/qla_init.c                   |    4 ++--
 drivers/staging/media/ipu3/ipu3-mmu.c             |    2 +-
 drivers/vdpa/vdpa_user/iova_domain.c              |    3 +--
 drivers/virtio/virtio_mem.c                       |    6 +++---
 fs/btrfs/zoned.c                                  |    5 +++--
 kernel/kcov.c                                     |    2 +-
 lib/test_vmalloc.c                                |   12 ++++++------
 28 files changed, 56 insertions(+), 52 deletions(-)

[PATCH 23/26] media: staging: imgu: use array_size

[Julia Lawall]

Use array_size to protect against multiplication overflows.

The changes were done using the following Coccinelle semantic patch:

// <smpl>
@@
    expression E1, E2;
    constant C1, C2;
    identifier alloc = {vmalloc,vzalloc};
@@
    
(
      alloc(C1 * C2,...)
|
      alloc(
-           (E1) * (E2)
+           array_size(E1, E2)
      ,...)
)
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>

---
 drivers/staging/media/ipu3/ipu3-mmu.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/media/ipu3/ipu3-mmu.c b/drivers/staging/media/ipu3/ipu3-mmu.c
index cb9bf5fb29a5..9c4adb815c94 100644
--- a/drivers/staging/media/ipu3/ipu3-mmu.c
+++ b/drivers/staging/media/ipu3/ipu3-mmu.c
@@ -464,7 +464,7 @@ struct imgu_mmu_info *imgu_mmu_init(struct device *parent, void __iomem *base)
 	 * Allocate the array of L2PT CPU pointers, initialized to zero,
 	 * which means the dummy L2PT allocated above.
 	 */
-	mmu->l2pts = vzalloc(IPU3_PT_PTES * sizeof(*mmu->l2pts));
+	mmu->l2pts = vzalloc(array_size(IPU3_PT_PTES, sizeof(*mmu->l2pts)));
 	if (!mmu->l2pts)
 		goto fail_l2pt;
 

Re: [PATCH 23/26] media: staging: imgu: use array_size

[Bingbu Cao]

Julia,

Thanks for your patch.

On 6/24/23 5:14 AM, Julia Lawall wrote:
> Use array_size to protect against multiplication overflows.
> 
> The changes were done using the following Coccinelle semantic patch:
> 
> // <smpl>
> @@
>     expression E1, E2;
>     constant C1, C2;
>     identifier alloc = {vmalloc,vzalloc};
> @@
>     
> (
>       alloc(C1 * C2,...)
> |
>       alloc(
> -           (E1) * (E2)
> +           array_size(E1, E2)
>       ,...)
> )
> // </smpl>
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
> 
> ---
>  drivers/staging/media/ipu3/ipu3-mmu.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/media/ipu3/ipu3-mmu.c b/drivers/staging/media/ipu3/ipu3-mmu.c
> index cb9bf5fb29a5..9c4adb815c94 100644
> --- a/drivers/staging/media/ipu3/ipu3-mmu.c
> +++ b/drivers/staging/media/ipu3/ipu3-mmu.c
> @@ -464,7 +464,7 @@ struct imgu_mmu_info *imgu_mmu_init(struct device *parent, void __iomem *base)
>  	 * Allocate the array of L2PT CPU pointers, initialized to zero,
>  	 * which means the dummy L2PT allocated above.
>  	 */
> -	mmu->l2pts = vzalloc(IPU3_PT_PTES * sizeof(*mmu->l2pts));
> +	mmu->l2pts = vzalloc(array_size(IPU3_PT_PTES, sizeof(*mmu->l2pts)));
>  	if (!mmu->l2pts)
>  		goto fail_l2pt;
>  
>

Reviewed-by: Bingbu Cao <bingbu.cao@intel.com>


-- 
Best regards,
Bingbu Cao

Re: [PATCH 23/26] media: staging: imgu: use array_size

[Julia Lawall]

On Fri, 23 Jun 2023, Julia Lawall wrote:

> Use array_size to protect against multiplication overflows.
>
> The changes were done using the following Coccinelle semantic patch:
>
> // <smpl>
> @@
>     expression E1, E2;
>     constant C1, C2;
>     identifier alloc = {vmalloc,vzalloc};
> @@
>
> (
>       alloc(C1 * C2,...)
> |
>       alloc(
> -           (E1) * (E2)
> +           array_size(E1, E2)
>       ,...)
> )
> // </smpl>
>
> Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
>
> ---
>  drivers/staging/media/ipu3/ipu3-mmu.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/staging/media/ipu3/ipu3-mmu.c b/drivers/staging/media/ipu3/ipu3-mmu.c
> index cb9bf5fb29a5..9c4adb815c94 100644
> --- a/drivers/staging/media/ipu3/ipu3-mmu.c
> +++ b/drivers/staging/media/ipu3/ipu3-mmu.c
> @@ -464,7 +464,7 @@ struct imgu_mmu_info *imgu_mmu_init(struct device *parent, void __iomem *base)
>  	 * Allocate the array of L2PT CPU pointers, initialized to zero,
>  	 * which means the dummy L2PT allocated above.
>  	 */
> -	mmu->l2pts = vzalloc(IPU3_PT_PTES * sizeof(*mmu->l2pts));
> +	mmu->l2pts = vzalloc(array_size(IPU3_PT_PTES, sizeof(*mmu->l2pts)));
>  	if (!mmu->l2pts)
>  		goto fail_l2pt;

I think that this patch can be dropped.  Since it is a multiplcation of
two constants, if there is an overflow, I guess the compiler would detect
it?

julia

Re: [PATCH 23/26] media: staging: imgu: use array_size

[Sakari Ailus]

Hi Julia, Bingbu,

On Tue, Jun 27, 2023 at 07:35:47PM +0200, Julia Lawall wrote:
> 
> 
> On Fri, 23 Jun 2023, Julia Lawall wrote:
> 
> > Use array_size to protect against multiplication overflows.
> >
> > The changes were done using the following Coccinelle semantic patch:
> >
> > // <smpl>
> > @@
> >     expression E1, E2;
> >     constant C1, C2;
> >     identifier alloc = {vmalloc,vzalloc};
> > @@
> >
> > (
> >       alloc(C1 * C2,...)
> > |
> >       alloc(
> > -           (E1) * (E2)
> > +           array_size(E1, E2)
> >       ,...)
> > )
> > // </smpl>
> >
> > Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
> >
> > ---
> >  drivers/staging/media/ipu3/ipu3-mmu.c |    2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/staging/media/ipu3/ipu3-mmu.c b/drivers/staging/media/ipu3/ipu3-mmu.c
> > index cb9bf5fb29a5..9c4adb815c94 100644
> > --- a/drivers/staging/media/ipu3/ipu3-mmu.c
> > +++ b/drivers/staging/media/ipu3/ipu3-mmu.c
> > @@ -464,7 +464,7 @@ struct imgu_mmu_info *imgu_mmu_init(struct device *parent, void __iomem *base)
> >  	 * Allocate the array of L2PT CPU pointers, initialized to zero,
> >  	 * which means the dummy L2PT allocated above.
> >  	 */
> > -	mmu->l2pts = vzalloc(IPU3_PT_PTES * sizeof(*mmu->l2pts));
> > +	mmu->l2pts = vzalloc(array_size(IPU3_PT_PTES, sizeof(*mmu->l2pts)));
> >  	if (!mmu->l2pts)
> >  		goto fail_l2pt;
> 
> I think that this patch can be dropped.  Since it is a multiplcation of
> two constants, if there is an overflow, I guess the compiler would detect
> it?

Indeed. vcalloc() would be perhaps nicer but the original isn't wrong
either.

-- 
Kind regards,

Sakari Ailus