[patch] iommu/amd: use after free in get_irq_table()

[patch] iommu/amd: use after free in get_irq_table()

[Dan Carpenter]

We should return NULL on error instead of the freed pointer.

Signed-off-by: Dan Carpenter <dan.carpenter-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index e78b8a4..a636d68 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -3867,6 +3867,7 @@ static struct irq_remap_table *get_irq_table(u16 devid, bool ioapic)
 	table->table = kmem_cache_alloc(amd_iommu_irq_cache, GFP_ATOMIC);
 	if (!table->table) {
 		kfree(table);
+		table = NULL;
 		goto out;
 	}
 

Re: [patch] iommu/amd: use after free in get_irq_table()

[Joerg Roedel]

On Tue, Oct 02, 2012 at 11:34:40AM +0300, Dan Carpenter wrote:
> We should return NULL on error instead of the freed pointer.
> 
> Signed-off-by: Dan Carpenter <dan.carpenter-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org>
> 
> diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
> index e78b8a4..a636d68 100644
> --- a/drivers/iommu/amd_iommu.c
> +++ b/drivers/iommu/amd_iommu.c
> @@ -3867,6 +3867,7 @@ static struct irq_remap_table *get_irq_table(u16 devid, bool ioapic)
>  	table->table = kmem_cache_alloc(amd_iommu_irq_cache, GFP_ATOMIC);
>  	if (!table->table) {
>  		kfree(table);
> +		table = NULL;
>  		goto out;
>  	}

Good catch. Thanks, applied.

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