| Message ID | 20210911102818.3804-1-len.baker@gmx.com |
|---|---|
| State | New |
| Headers | show |
| Series | net: mana: Prefer struct_size over open coded arithmetic | expand |
diff --git a/drivers/net/ethernet/microsoft/mana/hw_channel.c b/drivers/net/ethernet/microsoft/mana/hw_channel.c index 1a923fd99990..0efdc6c3c32a 100644 --- a/drivers/net/ethernet/microsoft/mana/hw_channel.c +++ b/drivers/net/ethernet/microsoft/mana/hw_channel.c @@ -398,9 +398,7 @@ static int mana_hwc_alloc_dma_buf(struct hw_channel_context *hwc, u16 q_depth, int err; u16 i; - dma_buf = kzalloc(sizeof(*dma_buf) + - q_depth * sizeof(struct hwc_work_request), - GFP_KERNEL); + dma_buf = kzalloc(struct_size(dma_buf, reqs, q_depth), GFP_KERNEL); if (!dma_buf) return -ENOMEM;
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 struct_size() helper to do the arithmetic instead of the argument "size + count * size" 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> --- drivers/net/ethernet/microsoft/mana/hw_channel.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) -- 2.25.1