| Message ID | 20190108171738.GA32297@embeddedor (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Luca Coelho |
| Headers | show |
| Series | iwlwifi: eeprom-parse: use struct_size() in kzalloc() | expand |
On Tue, 2019-01-08 at 11:17 -0600, Gustavo A. R. Silva wrote: > One of the more common cases of allocation size calculations is > finding the > size of a structure that has a zero-sized array at the end, along > with memory > for some number of elements for that array. For example: > > struct foo { > int stuff; > void *entry[]; > }; > > instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, > GFP_KERNEL); > > Instead of leaving these open-coded and prone to type mistakes, we > can now > use the new struct_size() helper: > > instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL); > > This code was detected with the help of Coccinelle. > > Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> > --- Applied to our internal tree, thanks! It will reach the mainline following our normal upstreaming process. -- Luca.
On 1/22/19 4:58 AM, Luciano Coelho wrote: > On Tue, 2019-01-08 at 11:17 -0600, Gustavo A. R. Silva wrote: >> One of the more common cases of allocation size calculations is >> finding the >> size of a structure that has a zero-sized array at the end, along >> with memory >> for some number of elements for that array. For example: >> >> struct foo { >> int stuff; >> void *entry[]; >> }; >> >> instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, >> GFP_KERNEL); >> >> Instead of leaving these open-coded and prone to type mistakes, we >> can now >> use the new struct_size() helper: >> >> instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL); >> >> This code was detected with the help of Coccinelle. >> >> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> >> --- > > Applied to our internal tree, thanks! It will reach the mainline > following our normal upstreaming process. > Great. :) Thanks, Luca. -- Gustavo
diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-eeprom-parse.c b/drivers/net/wireless/intel/iwlwifi/iwl-eeprom-parse.c index 75940ac406b9..04338c3a6205 100644 --- a/drivers/net/wireless/intel/iwlwifi/iwl-eeprom-parse.c +++ b/drivers/net/wireless/intel/iwlwifi/iwl-eeprom-parse.c @@ -850,8 +850,7 @@ iwl_parse_eeprom_data(struct device *dev, const struct iwl_cfg *cfg, if (WARN_ON(!cfg || !cfg->eeprom_params)) return NULL; - data = kzalloc(sizeof(*data) + - sizeof(struct ieee80211_channel) * IWL_NUM_CHANNELS, + data = kzalloc(struct_size(data, channels, IWL_NUM_CHANNELS), GFP_KERNEL); if (!data) return NULL;
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct foo { int stuff; void *entry[]; }; instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> --- drivers/net/wireless/intel/iwlwifi/iwl-eeprom-parse.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)