From ff917923f4fb9c83717ba135ee47d7e4c1567bb7 Mon Sep 17 00:00:00 2001 From: Muhammad Bilal Date: Tue, 28 Jul 2026 17:54:55 +0500 Subject: staging: rtl8723bs: fix OOB read in rtw_action_frame_parse() rtw_action_frame_parse() takes a frame_len parameter but never actually checks it before indexing into the frame body: const u8 *frame_body = frame + sizeof(struct ieee80211_hdr_3addr); ... c = frame_body[0]; ... a = frame_body[1]; frame_body already points 24 bytes (sizeof(struct ieee80211_hdr_3addr)) into frame, so reading frame_body[0] and frame_body[1] requires frame_len >= 26. A management action frame shorter than that (e.g. exactly 24 bytes, the minimum a malicious peer can send) causes a 1-2 byte out-of-bounds read. This is reachable from rtw_cfg80211_monitor_if_xmit_entry() and cfg80211_rtw_mgmt_tx() in ioctl_cfg80211.c, both of which pass attacker/user-influenced frame buffers and lengths straight through. Add the missing length check before frame_body is dereferenced. Fixes: 554c0a3abf216 ("staging: Add rtl8723bs sdio wifi driver") Cc: stable@vger.kernel.org Signed-off-by: Muhammad Bilal Link: https://patch.msgid.link/20260728125456.32359-3-meatuni001@gmail.com Signed-off-by: Greg Kroah-Hartman --- lib/net_utils.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) create mode 100644 lib/net_utils.c (limited to 'lib/net_utils.c') diff --git a/lib/net_utils.c b/lib/net_utils.c new file mode 100644 index 000000000..215cda672 --- /dev/null +++ b/lib/net_utils.c @@ -0,0 +1,27 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include + +bool mac_pton(const char *s, u8 *mac) +{ + int i; + + if (strnlen(s, MAC_ADDR_STR_LEN) < MAC_ADDR_STR_LEN) + return false; + + /* Don't dirty result unless string is valid MAC. */ + for (i = 0; i < ETH_ALEN; i++) { + if (!isxdigit(s[i * 3]) || !isxdigit(s[i * 3 + 1])) + return false; + if (i != ETH_ALEN - 1 && s[i * 3 + 2] != ':') + return false; + } + for (i = 0; i < ETH_ALEN; i++) { + mac[i] = (hex_to_bin(s[i * 3]) << 4) | hex_to_bin(s[i * 3 + 1]); + } + return true; +} +EXPORT_SYMBOL(mac_pton); -- cgit v1.3.1