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 --- tools/lib/vsprintf.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 tools/lib/vsprintf.c (limited to 'tools/lib/vsprintf.c') diff --git a/tools/lib/vsprintf.c b/tools/lib/vsprintf.c new file mode 100644 index 000000000..8780b4cda --- /dev/null +++ b/tools/lib/vsprintf.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include + +int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) +{ + int i = vsnprintf(buf, size, fmt, args); + ssize_t ssize = size; + + return (i >= ssize) ? (ssize - 1) : i; +} + +int scnprintf(char * buf, size_t size, const char * fmt, ...) +{ + ssize_t ssize = size; + va_list args; + int i; + + va_start(args, fmt); + i = vsnprintf(buf, size, fmt, args); + va_end(args); + + return (i >= ssize) ? (ssize - 1) : i; +} + +int scnprintf_pad(char * buf, size_t size, const char * fmt, ...) +{ + ssize_t ssize = size; + va_list args; + int i; + + va_start(args, fmt); + i = vscnprintf(buf, size, fmt, args); + va_end(args); + + if (i < (int) size) { + for (; i < (int) size; i++) + buf[i] = ' '; + buf[i] = 0x0; + } + + return (i >= ssize) ? (ssize - 1) : i; +} -- cgit v1.3.1