The find.h APIs are designed to be used only on unsigned long arguments.
This can technically result in a over-read, but it is harmless in this
case. Regardless, fix it to avoid the warning seen under -Warray-bounds,
which we'd like to enable globally:
In file included from ./include/linux/bitmap.h:9,
from drivers/iommu/intel/iommu.c:17:
drivers/iommu/intel/iommu.c: In function 'domain_context_mapping_one':
./include/linux/find.h:119:37: warning: array subscript 'long unsigned int[0]' is partly outside array bounds of 'int[1]' [-Warray-bounds]
119 | unsigned long val = *addr & GENMASK(size - 1, 0);
| ^~~~~
drivers/iommu/intel/iommu.c:2115:18: note: while referencing 'max_pde'
2115 | int pds, max_pde;
| ^~~~~~~
Signed-off-by: Kees Cook <[email protected]>
---
drivers/iommu/intel/iommu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index b6a8f3282411..99f9e8229384 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -2112,10 +2112,10 @@ static void domain_exit(struct dmar_domain *domain)
*/
static inline unsigned long context_get_sm_pds(struct pasid_table *table)
{
- int pds, max_pde;
+ unsigned long pds, max_pde;
max_pde = table->max_pasid >> PASID_PDE_SHIFT;
- pds = find_first_bit((unsigned long *)&max_pde, MAX_NR_PASID_BITS);
+ pds = find_first_bit(&max_pde, MAX_NR_PASID_BITS);
if (pds < 7)
return 0;
--
2.30.2
On Wed, Dec 15, 2021 at 3:24 PM Kees Cook <[email protected]> wrote:
>
> The find.h APIs are designed to be used only on unsigned long arguments.
> This can technically result in a over-read, but it is harmless in this
> case. Regardless, fix it to avoid the warning seen under -Warray-bounds,
> which we'd like to enable globally:
>
> In file included from ./include/linux/bitmap.h:9,
> from drivers/iommu/intel/iommu.c:17:
> drivers/iommu/intel/iommu.c: In function 'domain_context_mapping_one':
> ./include/linux/find.h:119:37: warning: array subscript 'long unsigned int[0]' is partly outside array bounds of 'int[1]' [-Warray-bounds]
> 119 | unsigned long val = *addr & GENMASK(size - 1, 0);
> | ^~~~~
> drivers/iommu/intel/iommu.c:2115:18: note: while referencing 'max_pde'
> 2115 | int pds, max_pde;
> | ^~~~~~~
>
> Signed-off-by: Kees Cook <[email protected]>
For all patches in this (not a) series
Acked-by: Yury Norov <[email protected]>
But can you explain, what for did you split this change? The
Documentation/process says: "Solve only one problem per patch.",
but here one problem is solved per 4 patches with identical
description.
I think it would be more logical to move-in this change as a single
commitment rather than random scattered patches.
Thanks,
Yury
> ---
> drivers/iommu/intel/iommu.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index b6a8f3282411..99f9e8229384 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -2112,10 +2112,10 @@ static void domain_exit(struct dmar_domain *domain)
> */
> static inline unsigned long context_get_sm_pds(struct pasid_table *table)
> {
> - int pds, max_pde;
> + unsigned long pds, max_pde;
>
> max_pde = table->max_pasid >> PASID_PDE_SHIFT;
> - pds = find_first_bit((unsigned long *)&max_pde, MAX_NR_PASID_BITS);
> + pds = find_first_bit(&max_pde, MAX_NR_PASID_BITS);
> if (pds < 7)
> return 0;
>
> --
> 2.30.2
>
On Wed, Dec 15, 2021 at 03:24:32PM -0800, Kees Cook wrote:
> The find.h APIs are designed to be used only on unsigned long arguments.
> This can technically result in a over-read, but it is harmless in this
> case. Regardless, fix it to avoid the warning seen under -Warray-bounds,
> which we'd like to enable globally:
>
> In file included from ./include/linux/bitmap.h:9,
> from drivers/iommu/intel/iommu.c:17:
> drivers/iommu/intel/iommu.c: In function 'domain_context_mapping_one':
> ./include/linux/find.h:119:37: warning: array subscript 'long unsigned int[0]' is partly outside array bounds of 'int[1]' [-Warray-bounds]
> 119 | unsigned long val = *addr & GENMASK(size - 1, 0);
> | ^~~~~
> drivers/iommu/intel/iommu.c:2115:18: note: while referencing 'max_pde'
> 2115 | int pds, max_pde;
> | ^~~~~~~
>
> Signed-off-by: Kees Cook <[email protected]>
> ---
> drivers/iommu/intel/iommu.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
Applied, thanks.