2019-06-18 01:44:44

by Hariprasad Kelam

Subject: [Patch v2] staging: rtl8723bs: os_dep: ioctl_linux: make use of kzalloc

kmalloc with memset can be replaced with kzalloc.

Signed-off-by: Hariprasad Kelam <[email protected]>
-----
changes in v2: Replace rtw_zmalloc with kzalloc
---
---
drivers/staging/rtl8723bs/os_dep/ioctl_linux.c | 12 +++---------
1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c b/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c
index ea50ec424..e050f20 100644
--- a/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c
+++ b/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c
@@ -477,14 +477,12 @@ static int wpa_set_encryption(struct net_device *dev, struct ieee_param *param,
if (wep_key_len > 0) {
wep_key_len = wep_key_len <= 5 ? 5 : 13;
wep_total_len = wep_key_len + FIELD_OFFSET(struct ndis_802_11_wep, KeyMaterial);
- pwep = rtw_malloc(wep_total_len);
+ pwep = kzalloc(wep_total_len, GFP_KERNEL);
if (pwep == NULL) {
RT_TRACE(_module_rtl871x_ioctl_os_c, _drv_err_, (" wpa_set_encryption: pwep allocate fail !!!\n"));
goto exit;
}

- memset(pwep, 0, wep_total_len);
-
pwep->KeyLength = wep_key_len;
pwep->Length = wep_total_len;

@@ -2142,12 +2140,10 @@ static int rtw_wx_set_enc_ext(struct net_device *dev,
int ret = 0;

param_len = sizeof(struct ieee_param) + pext->key_len;
- param = rtw_malloc(param_len);
+ param = kzalloc(param_len, GFP_KERNEL);
if (param == NULL)
return -1;

- memset(param, 0, param_len);
-
param->cmd = IEEE_CMD_SET_ENCRYPTION;
memset(param->sta_addr, 0xff, ETH_ALEN);

@@ -3513,14 +3509,12 @@ static int rtw_set_encryption(struct net_device *dev, struct ieee_param *param,
if (wep_key_len > 0) {
wep_key_len = wep_key_len <= 5 ? 5 : 13;
wep_total_len = wep_key_len + FIELD_OFFSET(struct ndis_802_11_wep, KeyMaterial);
- pwep = rtw_malloc(wep_total_len);
+ pwep = kzalloc(wep_total_len, GFP_KERNEL);
if (pwep == NULL) {
DBG_871X(" r871x_set_encryption: pwep allocate fail !!!\n");
goto exit;
}

- memset(pwep, 0, wep_total_len);
-
pwep->KeyLength = wep_key_len;
pwep->Length = wep_total_len;

--
2.7.4

2019-06-18 06:58:34

by Greg Kroah-Hartman

Subject: Re: [Patch v2] staging: rtl8723bs: os_dep: ioctl_linux: make use of kzalloc

On Tue, Jun 18, 2019 at 07:14:10AM +0530, Hariprasad Kelam wrote:
> kmalloc with memset can be replaced with kzalloc.

Yes, but did you audit the call-paths of this to ensure that GFP_KERNEL
is the correct value for kzalloc() here? If so, please document that in
the changelog.

thanks,

greg k-h

2019-06-18 08:58:30

by Dan Carpenter

Subject: Re: [Patch v2] staging: rtl8723bs: os_dep: ioctl_linux: make use of kzalloc

On Tue, Jun 18, 2019 at 07:14:10AM +0530, Hariprasad Kelam wrote:
> kmalloc with memset can be replaced with kzalloc.
>
> Signed-off-by: Hariprasad Kelam <[email protected]>
> -----
> changes in v2: Replace rtw_zmalloc with kzalloc
> ---
> ---


The changelog should say something like:

This patch is a cleanup which replaces rtw_malloc(wep_total_len)
with kzalloc() and removes the memset().

The rtw_malloc() does GFP_ATOMIC allocations when in_atomic() is true.
But as the comments for in_atomic() describe, the in_atomic() check
should not be used in driver code. The in_atomic() check is not
accurate when preempt is disabled.

In this code we are not in IRQ context and we are not holding any
spin_locks so GFP_KERNEL is safe.

regards,
dan carpenter