Despite carefully rewording the kerneldoc to describe the new direct
interaction with dma_range_map, it seems I managed to confuse myself in
removing the redundant force_aperture check and ended up making the code
not do that at all. This led to dma_range_maps inadvertently being able
to set iovad->start_pfn = 0, and all the nonsensical chaos which ensues
from there. Restore the correct behaviour of constraining base_pfn to
the domain aperture regardless of dma_range_map, and not trying to apply
dma_range_map constraints to the basic IOVA domain since they will be
properly handled with reserved regions later.
Reported-by: Jon Hunter <[email protected]>
Reported-by: Jerry Snitselaar <[email protected]>
Fixes: e28a114243d1 ("iommu/dma: Make limit checks self-contained")
Signed-off-by: Robin Murphy <[email protected]>
---
drivers/iommu/dma-iommu.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 89a53c2f2cf9..1ec89ca75c59 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -685,15 +685,15 @@ static int iommu_dma_init_domain(struct iommu_domain *domain, struct device *dev
/* Check the domain allows at least some access to the device... */
if (map) {
- dma_addr_t base = dma_range_map_min(map);
- if (base > domain->geometry.aperture_end ||
+ if (dma_range_map_min(map) > domain->geometry.aperture_end ||
dma_range_map_max(map) < domain->geometry.aperture_start) {
pr_warn("specified DMA range outside IOMMU capability\n");
return -EFAULT;
}
- /* ...then finally give it a kicking to make sure it fits */
- base_pfn = max(base, domain->geometry.aperture_start) >> order;
}
+ /* ...then finally give it a kicking to make sure it fits */
+ base_pfn = max_t(unsigned long, base_pfn,
+ domain->geometry.aperture_start >> order);
/* start_pfn is always nonzero for an already-initialised domain */
mutex_lock(&cookie->mutex);
--
2.39.2.101.g768bb238c484.dirty
On Mon, May 20, 2024 at 08:14:44PM GMT, Robin Murphy wrote:
> Despite carefully rewording the kerneldoc to describe the new direct
> interaction with dma_range_map, it seems I managed to confuse myself in
> removing the redundant force_aperture check and ended up making the code
> not do that at all. This led to dma_range_maps inadvertently being able
> to set iovad->start_pfn = 0, and all the nonsensical chaos which ensues
> from there. Restore the correct behaviour of constraining base_pfn to
> the domain aperture regardless of dma_range_map, and not trying to apply
> dma_range_map constraints to the basic IOVA domain since they will be
> properly handled with reserved regions later.
>
> Reported-by: Jon Hunter <[email protected]>
> Reported-by: Jerry Snitselaar <[email protected]>
> Fixes: e28a114243d1 ("iommu/dma: Make limit checks self-contained")
I'm seeing this upstream as ad4750b07d34 ("iommu/dma: Make limit checks self-contained") now.
> Signed-off-by: Robin Murphy <[email protected]>
> ---
Tested-by: Jerry Snitselaar <[email protected]>
Reviewed-by: Jerry Snitselaar <[email protected]>
> drivers/iommu/dma-iommu.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
> index 89a53c2f2cf9..1ec89ca75c59 100644
> --- a/drivers/iommu/dma-iommu.c
> +++ b/drivers/iommu/dma-iommu.c
> @@ -685,15 +685,15 @@ static int iommu_dma_init_domain(struct iommu_domain *domain, struct device *dev
>
> /* Check the domain allows at least some access to the device... */
> if (map) {
> - dma_addr_t base = dma_range_map_min(map);
> - if (base > domain->geometry.aperture_end ||
> + if (dma_range_map_min(map) > domain->geometry.aperture_end ||
> dma_range_map_max(map) < domain->geometry.aperture_start) {
> pr_warn("specified DMA range outside IOMMU capability\n");
> return -EFAULT;
> }
> - /* ...then finally give it a kicking to make sure it fits */
> - base_pfn = max(base, domain->geometry.aperture_start) >> order;
> }
> + /* ...then finally give it a kicking to make sure it fits */
> + base_pfn = max_t(unsigned long, base_pfn,
> + domain->geometry.aperture_start >> order);
>
> /* start_pfn is always nonzero for an already-initialised domain */
> mutex_lock(&cookie->mutex);
> --
> 2.39.2.101.g768bb238c484.dirty
>
On 21/05/2024 5:45 am, Jerry Snitselaar wrote:
> On Mon, May 20, 2024 at 08:14:44PM GMT, Robin Murphy wrote:
>> Despite carefully rewording the kerneldoc to describe the new direct
>> interaction with dma_range_map, it seems I managed to confuse myself in
>> removing the redundant force_aperture check and ended up making the code
>> not do that at all. This led to dma_range_maps inadvertently being able
>> to set iovad->start_pfn = 0, and all the nonsensical chaos which ensues
>> from there. Restore the correct behaviour of constraining base_pfn to
>> the domain aperture regardless of dma_range_map, and not trying to apply
>> dma_range_map constraints to the basic IOVA domain since they will be
>> properly handled with reserved regions later.
>>
>> Reported-by: Jon Hunter <[email protected]>
>> Reported-by: Jerry Snitselaar <[email protected]>
>> Fixes: e28a114243d1 ("iommu/dma: Make limit checks self-contained")
>
> I'm seeing this upstream as ad4750b07d34 ("iommu/dma: Make limit checks self-contained") now.
What, you mean when Linus pulls some patches I wrote he *doesn't* also
rebase my local development branch for me? /facepalm
Joerg, please shout if you'd like a resend for that.
>> Signed-off-by: Robin Murphy <[email protected]>
>> ---
>
> Tested-by: Jerry Snitselaar <[email protected]>
> Reviewed-by: Jerry Snitselaar <[email protected]>
Thanks!
Robin.
>> drivers/iommu/dma-iommu.c | 8 ++++----
>> 1 file changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
>> index 89a53c2f2cf9..1ec89ca75c59 100644
>> --- a/drivers/iommu/dma-iommu.c
>> +++ b/drivers/iommu/dma-iommu.c
>> @@ -685,15 +685,15 @@ static int iommu_dma_init_domain(struct iommu_domain *domain, struct device *dev
>>
>> /* Check the domain allows at least some access to the device... */
>> if (map) {
>> - dma_addr_t base = dma_range_map_min(map);
>> - if (base > domain->geometry.aperture_end ||
>> + if (dma_range_map_min(map) > domain->geometry.aperture_end ||
>> dma_range_map_max(map) < domain->geometry.aperture_start) {
>> pr_warn("specified DMA range outside IOMMU capability\n");
>> return -EFAULT;
>> }
>> - /* ...then finally give it a kicking to make sure it fits */
>> - base_pfn = max(base, domain->geometry.aperture_start) >> order;
>> }
>> + /* ...then finally give it a kicking to make sure it fits */
>> + base_pfn = max_t(unsigned long, base_pfn,
>> + domain->geometry.aperture_start >> order);
>>
>> /* start_pfn is always nonzero for an already-initialised domain */
>> mutex_lock(&cookie->mutex);
>> --
>> 2.39.2.101.g768bb238c484.dirty
>>
>
On Tue, May 21, 2024 at 04:14:50PM +0100, Robin Murphy wrote:
> Joerg, please shout if you'd like a resend for that.
No need to re-send. I applied with the correct commit-id.