| Message ID | 20240224181932.2720-1-erick.archer@gmx.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 848e34ca203046c9b967034596828472f08e4ac7 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | net: wwan: t7xx: Prefer struct_size over open coded arithmetic | expand |
On 24.02.2024 20:19, Erick Archer wrote: > This is an effort to get rid of all multiplications from allocation > functions in order to prevent integer overflows [1][2]. > > As the "port_prox" variable is a pointer to "struct port_proxy" and > this structure ends in a flexible array: > > struct port_proxy { > [...] > struct t7xx_port ports[]; > }; > > the preferred way in the kernel is to use the struct_size() helper to > do the arithmetic instead of the argument "size + size * count" in the > devm_kzalloc() function. > > This way, the code is more readable and 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/160 [2] > > Signed-off-by: Erick Archer <erick.archer@gmx.com> Reviewed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Hello: This patch was applied to netdev/net-next.git (main) by Jakub Kicinski <kuba@kernel.org>: On Sat, 24 Feb 2024 19:19:32 +0100 you wrote: > This is an effort to get rid of all multiplications from allocation > functions in order to prevent integer overflows [1][2]. > > As the "port_prox" variable is a pointer to "struct port_proxy" and > this structure ends in a flexible array: > > struct port_proxy { > [...] > struct t7xx_port ports[]; > }; > > [...] Here is the summary with links: - net: wwan: t7xx: Prefer struct_size over open coded arithmetic https://git.kernel.org/netdev/net-next/c/848e34ca2030 You are awesome, thank you!
diff --git a/drivers/net/wwan/t7xx/t7xx_port_proxy.c b/drivers/net/wwan/t7xx/t7xx_port_proxy.c index 8f5e01705af2..7d6388bf1d7c 100644 --- a/drivers/net/wwan/t7xx/t7xx_port_proxy.c +++ b/drivers/net/wwan/t7xx/t7xx_port_proxy.c @@ -543,8 +543,10 @@ static int t7xx_proxy_alloc(struct t7xx_modem *md) struct device *dev = &md->t7xx_dev->pdev->dev; struct port_proxy *port_prox; - port_prox = devm_kzalloc(dev, sizeof(*port_prox) + - sizeof(struct t7xx_port) * T7XX_MAX_POSSIBLE_PORTS_NUM, + port_prox = devm_kzalloc(dev, + struct_size(port_prox, + ports, + T7XX_MAX_POSSIBLE_PORTS_NUM), GFP_KERNEL); if (!port_prox) return -ENOMEM;
This is an effort to get rid of all multiplications from allocation functions in order to prevent integer overflows [1][2]. As the "port_prox" variable is a pointer to "struct port_proxy" and this structure ends in a flexible array: struct port_proxy { [...] struct t7xx_port ports[]; }; the preferred way in the kernel is to use the struct_size() helper to do the arithmetic instead of the argument "size + size * count" in the devm_kzalloc() function. This way, the code is more readable and 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/160 [2] Signed-off-by: Erick Archer <erick.archer@gmx.com> --- drivers/net/wwan/t7xx/t7xx_port_proxy.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) -- 2.25.1