Fixed scan buffer increasing with WEXT

We can now handle up to 65535 byte result buffer which is the maximum
due to WEXT using 16-bit length field. Previously, this was limited to
32768 bytes in practice even through we tried with 65536 and 131072
buffers which we just truncated into 0 in the 16-bit variable.

This more or less doubles the number of BSSes we can received from scan
results.
This commit is contained in:
Jouni Malinen 2009-02-05 12:00:23 +02:00 committed by Jouni Malinen
parent 94abc2f11b
commit 42f1ee7d1f
4 changed files with 11 additions and 3 deletions

View file

@ -2291,10 +2291,12 @@ static int i802_get_ht_scan_res(struct i802_driver_data *drv)
if (ioctl(drv->ioctl_sock, SIOCGIWSCAN, &iwr) == 0)
break;
if (errno == E2BIG && res_buf_len < 100000) {
if (errno == E2BIG && res_buf_len < 65535) {
os_free(res_buf);
res_buf = NULL;
res_buf_len *= 2;
if (res_buf_len > 65535)
res_buf_len = 65535; /* 16-bit length field */
wpa_printf(MSG_DEBUG, "Scan results did not fit - "
"trying larger buffer (%lu bytes)",
(unsigned long) res_buf_len);

View file

@ -1565,10 +1565,12 @@ static u8 * wpa_driver_nl80211_giwscan(struct wpa_driver_nl80211_data *drv,
if (ioctl(drv->ioctl_sock, SIOCGIWSCAN, &iwr) == 0)
break;
if (errno == E2BIG && res_buf_len < 100000) {
if (errno == E2BIG && res_buf_len < 65535) {
os_free(res_buf);
res_buf = NULL;
res_buf_len *= 2;
if (res_buf_len > 65535)
res_buf_len = 65535; /* 16-bit length field */
wpa_printf(MSG_DEBUG, "Scan results did not fit - "
"trying larger buffer (%lu bytes)",
(unsigned long) res_buf_len);

View file

@ -1140,10 +1140,12 @@ static u8 * wpa_driver_wext_giwscan(struct wpa_driver_wext_data *drv,
if (ioctl(drv->ioctl_sock, SIOCGIWSCAN, &iwr) == 0)
break;
if (errno == E2BIG && res_buf_len < 100000) {
if (errno == E2BIG && res_buf_len < 65535) {
os_free(res_buf);
res_buf = NULL;
res_buf_len *= 2;
if (res_buf_len > 65535)
res_buf_len = 65535; /* 16-bit length field */
wpa_printf(MSG_DEBUG, "Scan results did not fit - "
"trying larger buffer (%lu bytes)",
(unsigned long) res_buf_len);

View file

@ -3,6 +3,8 @@ ChangeLog for wpa_supplicant
????-??-?? - v0.7.0
* increased wpa_cli ping interval to 5 seconds and made this
configurable with a new command line options (-G<seconds>)
* fixed scan buffer processing with WEXT to handle up to 65535
byte result buffer (previously, limited to 32768 bytes)
2009-01-06 - v0.6.7
* added support for Wi-Fi Protected Setup (WPS)