lkml.org 
[lkml]   [2024]   [Feb]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH] wifi: brcm80211: handle pmk_op allocation failure
From
On 2/27/2024 12:42 PM, Joe Perches wrote:
> On Tue, 2024-02-27 at 12:21 +0100, Arend van Spriel wrote:
>> On 2/27/2024 9:06 AM, Duoming Zhou wrote:
>>> The kzalloc() in brcmf_pmksa_v3_op() will return null if the
>>> physical memory has run out. As a result, if we dereference
>>> the null value, the null pointer dereference bug will happen.
>>>
>>> Return -ENOMEM from brcmf_pmksa_v3_op() if kzalloc() fails
>>> for pmk_op.
>>
>> NAK (see below)
>>
>> Also this issue was reported earlier by Joe Perches. Not sure if he
>> wants to be mentioned as such.
>
> I think it's unimportant to be mentioned.
>
> I think it's more important that the code be researched
> that the simple return of -ENOMEM the appropriate fix
> and is handled by all possible callers of the function.

Right. That is what I did after which I replied on Feb 18 to your email.

https://lore.kernel.org/all/3e1f11b3-a689-4c8e-bfda-b43649db7106@broadcom.com/

Regards,
Arend

>>
>>> Fixes: a96202acaea4 ("wifi: brcmfmac: cfg80211: Add support for PMKID_V3 operations")
>>> Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
>>> ---
>>> drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 5 +++++
>>> 1 file changed, 5 insertions(+)
>>>
>>> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.cq b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
>>> index 28d6a30cc01..3b420b33188 100644
>>> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
>>> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
>>> @@ -4322,6 +4322,10 @@ brcmf_pmksa_v3_op(struct brcmf_if *ifp, struct cfg80211_pmksa *pmksa,
>>> int ret;
>>>
>>> pmk_op = kzalloc(sizeof(*pmk_op), GFP_KERNEL);
>>> + if (!pmk_op) {
>>> + ret = -ENOMEM;
>>> + goto out;
>>> + }
>>
>> There is really no need to introduce a new label for this. Although you
>> can kfree() a NULL pointer there is no need to do so when you know
>> already it is NULL. Just return -ENOMEM and be done with it.
>>
>> Regards,
>> Arend
>>
>>> pmk_op->version = cpu_to_le16(BRCMF_PMKSA_VER_3);
>>>
>>> if (!pmksa) {
>>> @@ -4340,6 +4344,7 @@ brcmf_pmksa_v3_op(struct brcmf_if *ifp, struct cfg80211_pmksa *pmksa,
>>> pmk_op->length = cpu_to_le16(length);
>>>
>>> ret = brcmf_fil_iovar_data_set(ifp, "pmkid_info", pmk_op, sizeof(*pmk_op));
>>> +out:
>>> kfree(pmk_op);
>>> return ret;
>>> }
>
[unhandled content-type:application/pkcs7-signature]
\
 
 \ /
  Last update: 2024-05-27 15:25    [W:0.037 / U:0.592 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site