Re: [PATCH net-next] nfp: use struct_size() in kzalloc()
From: Joe Perches <joe@perches.com>
Date: 2019-01-31 17:11:19
Also in:
lkml
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
[]
quoted hunk ↗ jump to hunk
diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-nvm-parse.c b/drivers/net/wireless/intel/iwlwifi/iwl-nvm-parse.c
[]
quoted hunk ↗ jump to hunk
@@ -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);