This is an effort to get rid of all multiplications from allocation
functions in order to prevent integer overflows [1].
As the cpu variable is a pointer to "struct bcm7038_l1_cpu" and this
structure ends in a flexible array:
struct bcm7038_l1_cpu {
void __iomem *map_base;
u32 mask_cache[];
};
the preferred way in the kernel is to use the struct_size() helper to
do the arithmetic instead of the argument "size + count * size" in the
kzalloc() function.
This way, the code is more readable and more safer.
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1]
Link: https://github.com/KSPP/linux/issues/162 [2]
Signed-off-by: Erick Archer <[email protected]>
---
drivers/irqchip/irq-bcm7038-l1.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/irqchip/irq-bcm7038-l1.c b/drivers/irqchip/irq-bcm7038-l1.c
index 24ca1d656adc..36e71af054e9 100644
--- a/drivers/irqchip/irq-bcm7038-l1.c
+++ b/drivers/irqchip/irq-bcm7038-l1.c
@@ -249,7 +249,7 @@ static int __init bcm7038_l1_init_one(struct device_node *dn,
return -EINVAL;
}
- cpu = intc->cpus[idx] = kzalloc(sizeof(*cpu) + n_words * sizeof(u32),
+ cpu = intc->cpus[idx] = kzalloc(struct_size(cpu, mask_cache, n_words),
GFP_KERNEL);
if (!cpu)
return -ENOMEM;
--
2.25.1
On 2/9/24 12:31, Erick Archer wrote:
> This is an effort to get rid of all multiplications from allocation
> functions in order to prevent integer overflows [1].
>
> As the cpu variable is a pointer to "struct bcm7038_l1_cpu" and this
> structure ends in a flexible array:
>
> struct bcm7038_l1_cpu {
> void __iomem *map_base;
> u32 mask_cache[];
> };
>
> the preferred way in the kernel is to use the struct_size() helper to
> do the arithmetic instead of the argument "size + count * size" in the
> kzalloc() function.
>
> This way, the code is more readable and more safer.
>
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1]
> Link: https://github.com/KSPP/linux/issues/162 [2]
>
> Signed-off-by: Erick Archer <[email protected]>
LGTM:
Reviewed-by: Gustavo A. R. Silva <[email protected]>
Thanks
--
Gustavo
> ---
> drivers/irqchip/irq-bcm7038-l1.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/irqchip/irq-bcm7038-l1.c b/drivers/irqchip/irq-bcm7038-l1.c
> index 24ca1d656adc..36e71af054e9 100644
> --- a/drivers/irqchip/irq-bcm7038-l1.c
> +++ b/drivers/irqchip/irq-bcm7038-l1.c
> @@ -249,7 +249,7 @@ static int __init bcm7038_l1_init_one(struct device_node *dn,
> return -EINVAL;
> }
>
> - cpu = intc->cpus[idx] = kzalloc(sizeof(*cpu) + n_words * sizeof(u32),
> + cpu = intc->cpus[idx] = kzalloc(struct_size(cpu, mask_cache, n_words),
> GFP_KERNEL);
> if (!cpu)
> return -ENOMEM;
> --
> 2.25.1
>
On Fri, Feb 09, 2024 at 07:31:28PM +0100, Erick Archer wrote:
> This is an effort to get rid of all multiplications from allocation
> functions in order to prevent integer overflows [1].
>
> As the cpu variable is a pointer to "struct bcm7038_l1_cpu" and this
> structure ends in a flexible array:
>
> struct bcm7038_l1_cpu {
> void __iomem *map_base;
> u32 mask_cache[];
> };
>
> the preferred way in the kernel is to use the struct_size() helper to
> do the arithmetic instead of the argument "size + count * size" in the
> kzalloc() function.
>
> This way, the code is more readable and more safer.
>
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1]
> Link: https://github.com/KSPP/linux/issues/162 [2]
>
> Signed-off-by: Erick Archer <[email protected]>
Yeah, looks right to me.
Reviewed-by: Kees Cook <[email protected]>
--
Kees Cook
On 2/9/2024 10:31 AM, Erick Archer wrote:
> This is an effort to get rid of all multiplications from allocation
> functions in order to prevent integer overflows [1].
>
> As the cpu variable is a pointer to "struct bcm7038_l1_cpu" and this
> structure ends in a flexible array:
>
> struct bcm7038_l1_cpu {
> void __iomem *map_base;
> u32 mask_cache[];
> };
>
> the preferred way in the kernel is to use the struct_size() helper to
> do the arithmetic instead of the argument "size + count * size" in the
> kzalloc() function.
>
> This way, the code is more readable and more safer.
>
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1]
> Link: https://github.com/KSPP/linux/issues/162 [2]
>
> Signed-off-by: Erick Archer <[email protected]>
Reviewed-by: Florian Fainelli <[email protected]>
--
Florian
The following commit has been merged into the irq/core branch of tip:
Commit-ID: e955a71f83598a347eb45af5576e7eb6cb5bf285
Gitweb: https://git.kernel.org/tip/e955a71f83598a347eb45af5576e7eb6cb5bf285
Author: Erick Archer <[email protected]>
AuthorDate: Fri, 09 Feb 2024 19:31:28 +01:00
Committer: Thomas Gleixner <[email protected]>
CommitterDate: Tue, 13 Feb 2024 10:53:15 +01:00
irqchip/irq-bcm7038-l1: Prefer struct_size over open coded arithmetic
This is an effort to get rid of all multiplications from allocation
functions in order to prevent integer overflows.
The cpu variable is a pointer to "struct bcm7038_l1_cpu" and this structure
ends in a flexible array:
struct bcm7038_l1_cpu {
void __iomem *map_base;
u32 mask_cache[];
};
The preferred way in the kernel is to use the struct_size() helper to
do the arithmetic instead of the argument "size + count * size" in the
kzalloc() function.
This way, the code is more readable and more safer.
Signed-off-by: Erick Archer <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Florian Fainelli <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Reviewed-by: Gustavo A. R. Silva <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1]
Link: https://github.com/KSPP/linux/issues/162 [2]
---
drivers/irqchip/irq-bcm7038-l1.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/irqchip/irq-bcm7038-l1.c b/drivers/irqchip/irq-bcm7038-l1.c
index 24ca1d6..36e71af 100644
--- a/drivers/irqchip/irq-bcm7038-l1.c
+++ b/drivers/irqchip/irq-bcm7038-l1.c
@@ -249,7 +249,7 @@ static int __init bcm7038_l1_init_one(struct device_node *dn,
return -EINVAL;
}
- cpu = intc->cpus[idx] = kzalloc(sizeof(*cpu) + n_words * sizeof(u32),
+ cpu = intc->cpus[idx] = kzalloc(struct_size(cpu, mask_cache, n_words),
GFP_KERNEL);
if (!cpu)
return -ENOMEM;