wifi: brcm80211: handle pmk_op allocation failure

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: a96202ac ("wifi: brcmfmac: cfg80211: Add support for PMKID_V3 operations")
Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20240229103153.18533-1-duoming@zju.edu.cn

drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c

@@ -4308,6 +4308,9 @@ 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)
+		return -ENOMEM;
+
 	pmk_op->version = cpu_to_le16(BRCMF_PMKSA_VER_3);
 
 	if (!pmksa) {