On Wed, 2019-01-30 at 18:38 -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; > struct boo entry[]; > }; > > instance = kzalloc(sizeof(struct foo) + count * sizeof(struct boo), > 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.
Might be useful to augment the script to include cases where the computed size is saved to a temporary and that temporary is used ala: https://patchwork.kernel.org/patch/10782453/ On Sat, 2019-01-26 at 20:42 +0800, YueHaibing wrote: > Use kmemdup rather than duplicating its implementation [] > diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-nvm-parse.c > b/drivers/net/wireless/intel/iwlwifi/iwl-nvm-parse.c [] > @@ -1196,13 +1196,9 @@ iwl_parse_nvm_mcc_info(struct device *dev, const > struct iwl_cfg *cfg, > regd_to_copy = sizeof(struct ieee80211_regdomain) + > valid_rules * sizeof(struct ieee80211_reg_rule); > - copy_rd = kzalloc(regd_to_copy, GFP_KERNEL); > - if (!copy_rd) { > + copy_rd = kmemdup(regd, regd_to_copy, GFP_KERNEL); This should probably be copy_rd = kmemdup(regd, struct_size(regd, reg_rules, valid_rules), GFP_KERNEL);