From: Alexandru Hossu Date: Fri, 22 May 2026 00:45:27 +0000 (+0200) Subject: staging: rtl8723bs: fix heap buffer overflow in rtw_cfg80211_set_wpa_ie() X-Git-Tag: v7.2-rc3~2^2~4 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5a752a616e756844388a1a45404db9fc29fec655;p=thirdparty%2Fkernel%2Flinux.git staging: rtl8723bs: fix heap buffer overflow in rtw_cfg80211_set_wpa_ie() supplicant_ie is a 256-byte array in struct security_priv. The WPA and WPA2 IE copy paths use: memcpy(padapter->securitypriv.supplicant_ie, &pwpa[0], wpa_ielen + 2); where wpa_ielen is the raw IE length field (u8, 0-255). When a local user supplies a connect request via nl80211 with a crafted WPA IE of length 255, wpa_ielen + 2 equals 257, overflowing the 256-byte buffer by one byte into the adjacent last_mic_err_time field. rtw_parse_wpa_ie() does not prevent this: its length consistency check compares *(wpa_ie+1) against (u8)(wpa_ie_len-2), which is (u8)(255) == 255 when wpa_ie_len = 257, so the check passes silently. Add explicit bounds checks for both the WPA and WPA2 paths before the memcpy, rejecting any IE whose total size (wpa_ielen + 2) exceeds the supplicant_ie buffer. Fixes: 554c0a3abf21 ("staging: Add rtl8723bs sdio wifi driver") Cc: stable Reviewed-by: Luka Gejak Signed-off-by: Alexandru Hossu Link: https://patch.msgid.link/20260522004531.1038924-4-hossu.alexandru@gmail.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c b/drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c index 1484336d7551..6a97afd89dc7 100644 --- a/drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c +++ b/drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c @@ -1446,6 +1446,10 @@ static int rtw_cfg80211_set_wpa_ie(struct adapter *padapter, u8 *pie, size_t iel pwpa = rtw_get_wpa_ie(buf, &wpa_ielen, ielen); if (pwpa && wpa_ielen > 0) { + if (wpa_ielen + 2 > sizeof(padapter->securitypriv.supplicant_ie)) { + ret = -EINVAL; + goto exit; + } if (rtw_parse_wpa_ie(pwpa, wpa_ielen + 2, &group_cipher, &pairwise_cipher, NULL) == _SUCCESS) { padapter->securitypriv.dot11AuthAlgrthm = dot11AuthAlgrthm_8021X; padapter->securitypriv.ndisauthtype = Ndis802_11AuthModeWPAPSK; @@ -1455,6 +1459,10 @@ static int rtw_cfg80211_set_wpa_ie(struct adapter *padapter, u8 *pie, size_t iel pwpa2 = rtw_get_wpa2_ie(buf, &wpa2_ielen, ielen); if (pwpa2 && wpa2_ielen > 0) { + if (wpa2_ielen + 2 > sizeof(padapter->securitypriv.supplicant_ie)) { + ret = -EINVAL; + goto exit; + } if (rtw_parse_wpa2_ie(pwpa2, wpa2_ielen + 2, &group_cipher, &pairwise_cipher, NULL) == _SUCCESS) { padapter->securitypriv.dot11AuthAlgrthm = dot11AuthAlgrthm_8021X; padapter->securitypriv.ndisauthtype = Ndis802_11AuthModeWPA2PSK;