There is a regular need in the kernel to provide a way to declare having
a dynamically sized set of trailing elements in a structure. Kernel code
should always use “flexible array members”[1] for these cases. The older
style of one-element or zero-length arrays should no longer be used[2].
Refactor the code according to the use of a flexible-array member in
struct phm_vce_clock_voltage_dependency_table, instead of a one-element array,
and use the struct_size() helper to calculate the size for the allocation.
Also, save some heap space as the original code is multiplying
table->numEntries by sizeof(struct phm_vce_clock_voltage_dependency_table)
when it should have multiplied it by sizeof(struct phm_vce_clock_voltage_dependency_record)
instead.
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arrays
Build-tested-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/5f7c5d35.pJToGs3H9khZK6ws%25lkp@intel.com/
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
struct phm_vce_clock_voltage_dependency_table {
uint8_t count;
- struct phm_vce_clock_voltage_dependency_record entries[1];
+ struct phm_vce_clock_voltage_dependency_record entries[];
};
const ATOM_PPLIB_VCE_Clock_Voltage_Limit_Table *table,
const VCEClockInfoArray *array)
{
- unsigned long table_size, i;
+ unsigned long i;
struct phm_vce_clock_voltage_dependency_table *vce_table = NULL;
- table_size = sizeof(unsigned long) +
- sizeof(struct phm_vce_clock_voltage_dependency_table)
- * table->numEntries;
-
- vce_table = kzalloc(table_size, GFP_KERNEL);
- if (NULL == vce_table)
+ vce_table = kzalloc(struct_size(vce_table, entries, table->numEntries),
+ GFP_KERNEL);
+ if (!vce_table)
return -ENOMEM;
vce_table->count = table->numEntries;