| Message ID | 20240128115236.4791-1-erick.archer@gmx.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | dmaengine: pl08x: Use kcalloc() instead of kzalloc() | expand |
On 1/28/24 05:52, Erick Archer wrote: > This is an effort to get rid of all multiplications from allocation > functions in order to prevent integer overflows [1]. > > Here the multiplication is obviously safe because the "channels" > member can only be 8 or 2. This value is set when the "vendor_data" > structs are initialized. > > static struct vendor_data vendor_pl080 = { > [...] > .channels = 8, > [...] > }; > > static struct vendor_data vendor_nomadik = { > [...] > .channels = 8, > [...] > }; > > static struct vendor_data vendor_pl080s = { > [...] > .channels = 8, > [...] > }; > > static struct vendor_data vendor_pl081 = { > [...] > .channels = 2, > [...] > }; > > However, using kcalloc() is more appropriate [1] and improves > readability. This patch has no effect on runtime behavior. > > Link: https://github.com/KSPP/linux/issues/162 [1] > Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1] > Signed-off-by: Erick Archer <erick.archer@gmx.com> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Thanks!
diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c index eea8bd33b4b7..e40766108787 100644 --- a/drivers/dma/amba-pl08x.c +++ b/drivers/dma/amba-pl08x.c @@ -2855,8 +2855,8 @@ static int pl08x_probe(struct amba_device *adev, const struct amba_id *id) } /* Initialize physical channels */ - pl08x->phy_chans = kzalloc((vd->channels * sizeof(*pl08x->phy_chans)), - GFP_KERNEL); + pl08x->phy_chans = kcalloc(vd->channels, sizeof(*pl08x->phy_chans), + GFP_KERNEL); if (!pl08x->phy_chans) { ret = -ENOMEM; goto out_no_phychans;
This is an effort to get rid of all multiplications from allocation functions in order to prevent integer overflows [1]. Here the multiplication is obviously safe because the "channels" member can only be 8 or 2. This value is set when the "vendor_data" structs are initialized. static struct vendor_data vendor_pl080 = { [...] .channels = 8, [...] }; static struct vendor_data vendor_nomadik = { [...] .channels = 8, [...] }; static struct vendor_data vendor_pl080s = { [...] .channels = 8, [...] }; static struct vendor_data vendor_pl081 = { [...] .channels = 2, [...] }; However, using kcalloc() is more appropriate [1] and improves readability. This patch has no effect on runtime behavior. Link: https://github.com/KSPP/linux/issues/162 [1] Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1] Signed-off-by: Erick Archer <erick.archer@gmx.com> --- drivers/dma/amba-pl08x.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) -- 2.25.1