| Message ID | 20210905153707.9638-1-len.baker@gmx.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | tifm: Prefer struct_size over open coded arithmetic | expand |
diff --git a/drivers/misc/tifm_core.c b/drivers/misc/tifm_core.c index 667e574a7df2..9babf171a035 100644 --- a/drivers/misc/tifm_core.c +++ b/drivers/misc/tifm_core.c @@ -177,8 +177,7 @@ struct tifm_adapter *tifm_alloc_adapter(unsigned int num_sockets, { struct tifm_adapter *fm; - fm = kzalloc(sizeof(struct tifm_adapter) - + sizeof(struct tifm_dev*) * num_sockets, GFP_KERNEL); + fm = kzalloc(struct_size(fm, sockets, num_sockets), GFP_KERNEL); if (fm) { fm->dev.class = &tifm_adapter_class; fm->dev.parent = dev;
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 + 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> --- drivers/misc/tifm_core.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) -- 2.25.1