| Message ID | 20190403164052.GA26381@embeddedor (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | ae187ba915412d20de8a6470ebaa7670c4d1e1e5 |
| Delegated to: | Kalle Valo |
| Headers | show |
| Series | [next] mwifiex: use struct_size() in kzalloc() | expand |
"Gustavo A. R. Silva" <gustavo@embeddedor.com> 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[]; > }; > > 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 regd_size 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> Patch applied to wireless-drivers-next.git, thanks. ae187ba91541 mwifiex: use struct_size() in kzalloc()
diff --git a/drivers/net/wireless/marvell/mwifiex/sta_cmdresp.c b/drivers/net/wireless/marvell/mwifiex/sta_cmdresp.c index 69e3b624adbb..24b33e20e7a9 100644 --- a/drivers/net/wireless/marvell/mwifiex/sta_cmdresp.c +++ b/drivers/net/wireless/marvell/mwifiex/sta_cmdresp.c @@ -1025,17 +1025,14 @@ mwifiex_create_custom_regdomain(struct mwifiex_private *priv, struct ieee80211_regdomain *regd; struct ieee80211_reg_rule *rule; bool new_rule; - int regd_size, idx, freq, prev_freq = 0; + int idx, freq, prev_freq = 0; u32 bw, prev_bw = 0; u8 chflags, prev_chflags = 0, valid_rules = 0; if (WARN_ON_ONCE(num_chan > NL80211_MAX_SUPP_REG_RULES)) return ERR_PTR(-EINVAL); - regd_size = sizeof(struct ieee80211_regdomain) + - num_chan * sizeof(struct ieee80211_reg_rule); - - regd = kzalloc(regd_size, GFP_KERNEL); + regd = kzalloc(struct_size(regd, reg_rules, num_chan), GFP_KERNEL); if (!regd) return ERR_PTR(-ENOMEM);
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 regd_size 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> --- drivers/net/wireless/marvell/mwifiex/sta_cmdresp.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-)