From: Wen Huang Date: Thu, 28 Nov 2019 18:51:04 +0800 Subject: libertas: Fix two buffer overflows at parsing bss descriptor Origin: https://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers.git/commit/?id=e5e884b42639c74b5b57dc277909915c0aefc8bb Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2019-14896 Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2019-14897 add_ie_rates() copys rates without checking the length in bss descriptor from remote AP.when victim connects to remote attacker, this may trigger buffer overflow. lbs_ibss_join_existing() copys rates without checking the length in bss descriptor from remote IBSS node.when victim connects to remote attacker, this may trigger buffer overflow. Fix them by putting the length check before performing copy. This fix addresses CVE-2019-14896 and CVE-2019-14897. This also fix build warning of mixed declarations and code. Reported-by: kbuild test robot Signed-off-by: Wen Huang Signed-off-by: Kalle Valo --- drivers/net/wireless/marvell/libertas/cfg.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/drivers/net/wireless/marvell/libertas/cfg.c +++ b/drivers/net/wireless/marvell/libertas/cfg.c @@ -273,6 +273,10 @@ add_ie_rates(u8 *tlv, const u8 *ie, int int hw, ap, ap_max = ie[1]; u8 hw_rate; + if (ap_max > MAX_RATES) { + lbs_deb_assoc("invalid rates\n"); + return tlv; + } /* Advance past IE header */ ie += 2; @@ -1717,6 +1721,9 @@ static int lbs_ibss_join_existing(struct struct cmd_ds_802_11_ad_hoc_join cmd; u8 preamble = RADIO_PREAMBLE_SHORT; int ret = 0; + int hw, i; + u8 rates_max; + u8 *rates; /* TODO: set preamble based on scan result */ ret = lbs_set_radio(priv, preamble, 1); @@ -1775,9 +1782,12 @@ static int lbs_ibss_join_existing(struct if (!rates_eid) { lbs_add_rates(cmd.bss.rates); } else { - int hw, i; - u8 rates_max = rates_eid[1]; - u8 *rates = cmd.bss.rates; + rates_max = rates_eid[1]; + if (rates_max > MAX_RATES) { + lbs_deb_join("invalid rates"); + goto out; + } + rates = cmd.bss.rates; for (hw = 0; hw < ARRAY_SIZE(lbs_rates); hw++) { u8 hw_rate = lbs_rates[hw].bitrate / 5; for (i = 0; i < rates_max; i++) {