2023-08-26 09:50:45

by Yu Liao

Subject: [PATCH v2 2/2] ACPI: NFIT: use struct_size() helper

Make use of the struct_size() helper instead of an open-coded version,
in order to avoid any potential type mistakes or integer overflows that,
in the worst scenario, could lead to heap overflows.

Signed-off-by: Yu Liao <[email protected]>
Reviewed-by: Dave Jiang <[email protected]>
---
drivers/acpi/nfit/core.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 305f590c54a8..2f7217600307 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -712,8 +712,7 @@ static bool add_spa(struct acpi_nfit_desc *acpi_desc,
}
}

- nfit_spa = devm_kzalloc(dev, sizeof(*nfit_spa) + sizeof_spa(spa),
- GFP_KERNEL);
+ nfit_spa = devm_kzalloc(dev, struct_size(nfit_spa, spa, 1), GFP_KERNEL);
if (!nfit_spa)
return false;
INIT_LIST_HEAD(&nfit_spa->list);
@@ -741,7 +740,7 @@ static bool add_memdev(struct acpi_nfit_desc *acpi_desc,
return true;
}

- nfit_memdev = devm_kzalloc(dev, sizeof(*nfit_memdev) + sizeof(*memdev),
+ nfit_memdev = devm_kzalloc(dev, struct_size(nfit_memdev, memdev, 1),
GFP_KERNEL);
if (!nfit_memdev)
return false;
@@ -812,8 +811,7 @@ static bool add_dcr(struct acpi_nfit_desc *acpi_desc,
return true;
}

- nfit_dcr = devm_kzalloc(dev, sizeof(*nfit_dcr) + sizeof(*dcr),
- GFP_KERNEL);
+ nfit_dcr = devm_kzalloc(dev, struct_size(nfit_dcr, dcr, 1), GFP_KERNEL);
if (!nfit_dcr)
return false;
INIT_LIST_HEAD(&nfit_dcr->list);
@@ -855,7 +853,7 @@ static size_t sizeof_idt(struct acpi_nfit_interleave *idt)
{
if (idt->header.length < sizeof(*idt))
return 0;
- return sizeof(*idt) + sizeof(u32) * idt->line_count;
+ return struct_size(idt, line_offset, idt->line_count);
}

static bool add_idt(struct acpi_nfit_desc *acpi_desc,
--
2.25.1

2023-09-15 23:50:56

by Ira Weiny

Subject: Re: [PATCH v2 2/2] ACPI: NFIT: use struct_size() helper

Yu Liao wrote:
> Make use of the struct_size() helper instead of an open-coded version,
> in order to avoid any potential type mistakes or integer overflows that,
> in the worst scenario, could lead to heap overflows.
>
> Signed-off-by: Yu Liao <[email protected]>
> Reviewed-by: Dave Jiang <[email protected]>

Reviewed-by: Ira Weiny <[email protected]>

> ---
> drivers/acpi/nfit/core.c | 10 ++++------
> 1 file changed, 4 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
> index 305f590c54a8..2f7217600307 100644
> --- a/drivers/acpi/nfit/core.c
> +++ b/drivers/acpi/nfit/core.c
> @@ -712,8 +712,7 @@ static bool add_spa(struct acpi_nfit_desc *acpi_desc,
> }
> }
>
> - nfit_spa = devm_kzalloc(dev, sizeof(*nfit_spa) + sizeof_spa(spa),
> - GFP_KERNEL);
> + nfit_spa = devm_kzalloc(dev, struct_size(nfit_spa, spa, 1), GFP_KERNEL);
> if (!nfit_spa)
> return false;
> INIT_LIST_HEAD(&nfit_spa->list);
> @@ -741,7 +740,7 @@ static bool add_memdev(struct acpi_nfit_desc *acpi_desc,
> return true;
> }
>
> - nfit_memdev = devm_kzalloc(dev, sizeof(*nfit_memdev) + sizeof(*memdev),
> + nfit_memdev = devm_kzalloc(dev, struct_size(nfit_memdev, memdev, 1),
> GFP_KERNEL);
> if (!nfit_memdev)
> return false;
> @@ -812,8 +811,7 @@ static bool add_dcr(struct acpi_nfit_desc *acpi_desc,
> return true;
> }
>
> - nfit_dcr = devm_kzalloc(dev, sizeof(*nfit_dcr) + sizeof(*dcr),
> - GFP_KERNEL);
> + nfit_dcr = devm_kzalloc(dev, struct_size(nfit_dcr, dcr, 1), GFP_KERNEL);
> if (!nfit_dcr)
> return false;
> INIT_LIST_HEAD(&nfit_dcr->list);
> @@ -855,7 +853,7 @@ static size_t sizeof_idt(struct acpi_nfit_interleave *idt)
> {
> if (idt->header.length < sizeof(*idt))
> return 0;
> - return sizeof(*idt) + sizeof(u32) * idt->line_count;
> + return struct_size(idt, line_offset, idt->line_count);
> }
>
> static bool add_idt(struct acpi_nfit_desc *acpi_desc,
> --
> 2.25.1
>