p71924506
/
linux_old1
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

nl80211: Use struct_size() in kzalloc() 

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[];
};

size = sizeof(struct foo) + count * sizeof(struct boo);
instance = kzalloc(size, 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)

Notice that, in this case, variable size_of_regd is not necessary,
hence it is removed.

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Gustavo A. R. Silva 2019-04-03 10:37:44 -05:00 committed by Johannes Berg
parent 9f8c7136e8
commit 391d132cbe
1 changed files with 3 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
net/wireless/nl80211.c
View File

@ -3876,8 +3876,7 @@ static struct cfg80211_acl_data *parse_acl_data(struct wiphy *wiphy,
if (n_entries > wiphy->max_acl_mac_addrs) if (n_entries > wiphy->max_acl_mac_addrs)
return ERR_PTR(-ENOTSUPP); return ERR_PTR(-ENOTSUPP);
acl = kzalloc(sizeof(*acl) + (sizeof(struct mac_address) * n_entries), acl = kzalloc(struct_size(acl, mac_addrs, n_entries), GFP_KERNEL);
GFP_KERNEL);
if (!acl) if (!acl)
return ERR_PTR(-ENOMEM); return ERR_PTR(-ENOMEM);
@ -6916,7 +6915,7 @@ static int nl80211_set_reg(struct sk_buff *skb, struct genl_info *info)
struct nlattr *nl_reg_rule; struct nlattr *nl_reg_rule;
char *alpha2; char *alpha2;
int rem_reg_rules, r; int rem_reg_rules, r;
u32 num_rules = 0, rule_idx = 0, size_of_regd; u32 num_rules = 0, rule_idx = 0;
enum nl80211_dfs_regions dfs_region = NL80211_DFS_UNSET; enum nl80211_dfs_regions dfs_region = NL80211_DFS_UNSET;
struct ieee80211_regdomain *rd; struct ieee80211_regdomain *rd;
@ -6941,10 +6940,7 @@ static int nl80211_set_reg(struct sk_buff *skb, struct genl_info *info)
if (!reg_is_valid_request(alpha2)) if (!reg_is_valid_request(alpha2))
return -EINVAL; return -EINVAL;
size_of_regd = sizeof(struct ieee80211_regdomain) + rd = kzalloc(struct_size(rd, reg_rules, num_rules), GFP_KERNEL);
num_rules * sizeof(struct ieee80211_reg_rule);
rd = kzalloc(size_of_regd, GFP_KERNEL);
if (!rd) if (!rd)
return -ENOMEM; return -ENOMEM;