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.
Fixes: a96202acaea4 ("wifi: brcmfmac: cfg80211: Add support for PMKID_V3 operations")
Signed-off-by: Duoming Zhou <[email protected]>
---
Changes in v2:
- Drop the new label and just return -ENOMEM.
drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
index 28d6a30cc01..7af6d6448b9 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
@@ -4322,6 +4322,9 @@ 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;
+
pmk_op->version = cpu_to_le16(BRCMF_PMKSA_VER_3);
if (!pmksa) {
--
2.17.1
On February 27, 2024 10:34:08 PM PST, Duoming Zhou <[email protected]> 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.
>
>Fixes: a96202acaea4 ("wifi: brcmfmac: cfg80211: Add support for PMKID_V3 operations")
>Signed-off-by: Duoming Zhou <[email protected]>
>---
>Changes in v2:
> - Drop the new label and just return -ENOMEM.
>
> drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 3 +++
> 1 file changed, 3 insertions(+)
>
>diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
>index 28d6a30cc01..7af6d6448b9 100644
>--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
>+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
>@@ -4322,6 +4322,9 @@ 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;
This doesn't fix anything. It doesn't stop the execution path; it'll continue and immediately dereference the NULL pmk_op in the next line...
>+
> pmk_op->version = cpu_to_le16(BRCMF_PMKSA_VER_3);
>
> if (!pmksa) {
--
Kees Cook
On February 28, 2024 3:48:18 PM Kees Cook <[email protected]> wrote:
> On February 27, 2024 10:34:08 PM PST, Duoming Zhou <[email protected]> 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.
>>
>> Fixes: a96202acaea4 ("wifi: brcmfmac: cfg80211: Add support for PMKID_V3
>> operations")
>> Signed-off-by: Duoming Zhou <[email protected]>
>> ---
>> Changes in v2:
>> - Drop the new label and just return -ENOMEM.
>>
>> drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 3 +++
>> 1 file changed, 3 insertions(+)
>>
>> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
>> b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
>> index 28d6a30cc01..7af6d6448b9 100644
>> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
>> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
>> @@ -4322,6 +4322,9 @@ 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;
>
> This doesn't fix anything. It doesn't stop the execution path; it'll
> continue and immediately dereference the NULL pmk_op in the next line...
Crap. Do I look bad :-( Thanks for catching my blunder. I was seeing what I
wanted to see I guess.
Regards,
Arend
>
>> +
>> pmk_op->version = cpu_to_le16(BRCMF_PMKSA_VER_3);
>>
>> if (!pmksa) {
>
> --
> Kees Cook