i3c/master/mipi-i3c-hci: Prefer kcalloc over open coded arithmetic

As noted in the "Deprecated Interfaces, Language Features, Attributes,
and Conventions" documentation [1], size calculations (especially
multiplication) should not be performed in memory allocator (or similar)
function arguments due to the risk of them overflowing. This could lead
to values wrapping around and a smaller allocation being made than the
caller was expecting. Using those allocations could lead to linear
overflows of heap memory and other misbehaviors.

So, use the purpose specific kcalloc() function instead of the argument
size * count in the kzalloc() function.

[1] https://www.kernel.org/doc/html/v5.14/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments

Signed-off-by: Len Baker <len.baker@gmx.com>
Acked-by: Nicolas Pitre <npitre@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210912155135.7541-1-len.baker@gmx.com

diff --git a/drivers/i3c/master/mipi-i3c-hci/hci.h b/drivers/i3c/master/mipi-i3c-hci/hci.h
index 80beb1d..f109923 100644 (file)
--- a/drivers/i3c/master/mipi-i3c-hci/hci.h
+++ b/drivers/i3c/master/mipi-i3c-hci/hci.h
@@ -98,7 +98,7 @@ struct hci_xfer {
 
 static inline struct hci_xfer *hci_alloc_xfer(unsigned int n)
 {
-       return kzalloc(sizeof(struct hci_xfer) * n, GFP_KERNEL);
+       return kcalloc(n, sizeof(struct hci_xfer), GFP_KERNEL);
 }
 
 static inline void hci_free_xfer(struct hci_xfer *xfer, unsigned int n)