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 --- Documentation/admin-guide/edid.rst | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) create mode 100644 Documentation/admin-guide/edid.rst (limited to 'Documentation/admin-guide/edid.rst') diff --git a/Documentation/admin-guide/edid.rst b/Documentation/admin-guide/edid.rst new file mode 100644 index 000000000..1a9b965aa --- /dev/null +++ b/Documentation/admin-guide/edid.rst @@ -0,0 +1,27 @@ +.. SPDX-License-Identifier: GPL-2.0 + +==== +EDID +==== + +In the good old days when graphics parameters were configured explicitly +in a file called xorg.conf, even broken hardware could be managed. + +Today, with the advent of Kernel Mode Setting, a graphics board is +either correctly working because all components follow the standards - +or the computer is unusable, because the screen remains dark after +booting or it displays the wrong area. Cases when this happens are: + +- The graphics board does not recognize the monitor. +- The graphics board is unable to detect any EDID data. +- The graphics board incorrectly forwards EDID data to the driver. +- The monitor sends no or bogus EDID data. +- A KVM sends its own EDID data instead of querying the connected monitor. + +Adding the kernel parameter "nomodeset" helps in most cases, but causes +restrictions later on. + +As a remedy for such situations, the kernel configuration item +CONFIG_DRM_LOAD_EDID_FIRMWARE was introduced. It allows to provide an +individually prepared or corrected EDID data set in the /lib/firmware +directory from where it is loaded via the firmware interface. -- cgit v1.3.1