3.16.70-rc1 review patch. If anyone has any objections, please let me know.
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From: Takashi Iwai tiwai@suse.de
commit 13ec7f10b87f5fc04c4ccbd491c94c7980236a74 upstream.
mwifiex_update_bss_desc_with_ie() calls memcpy() unconditionally in a couple places without checking the destination size. Since the source is given from user-space, this may trigger a heap buffer overflow.
Fix it by putting the length check before performing memcpy().
This fix addresses CVE-2019-3846.
Reported-by: huangwen huangwen@venustech.com.cn Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Kalle Valo kvalo@codeaurora.org [bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- drivers/net/wireless/mwifiex/scan.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/drivers/net/wireless/mwifiex/scan.c +++ b/drivers/net/wireless/mwifiex/scan.c @@ -1171,6 +1171,8 @@ int mwifiex_update_bss_desc_with_ie(stru } switch (element_id) { case WLAN_EID_SSID: + if (element_len > IEEE80211_MAX_SSID_LEN) + return -EINVAL; bss_entry->ssid.ssid_len = element_len; memcpy(bss_entry->ssid.ssid, (current_ptr + 2), element_len); @@ -1180,6 +1182,8 @@ int mwifiex_update_bss_desc_with_ie(stru break;
case WLAN_EID_SUPP_RATES: + if (element_len > MWIFIEX_SUPPORTED_RATES) + return -EINVAL; memcpy(bss_entry->data_rates, current_ptr + 2, element_len); memcpy(bss_entry->supported_rates, current_ptr + 2,