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/sysctl/debug.rst | 52 ++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 Documentation/admin-guide/sysctl/debug.rst (limited to 'Documentation/admin-guide/sysctl/debug.rst') diff --git a/Documentation/admin-guide/sysctl/debug.rst b/Documentation/admin-guide/sysctl/debug.rst new file mode 100644 index 000000000..506bd5e48 --- /dev/null +++ b/Documentation/admin-guide/sysctl/debug.rst @@ -0,0 +1,52 @@ +================ +/proc/sys/debug/ +================ + +These files show up in ``/proc/sys/debug/``, depending on the +kernel configuration: + +.. contents:: :local: + +exception-trace +=============== + +This flag controls whether the kernel prints information about unhandled +signals (like segmentation faults) to the kernel log (``dmesg``). + +- ``0``: Unhandled signals are not traced. +- ``1``: Information about unhandled signals is printed. + +The default value is ``1`` on most architectures (like x86, MIPS, RISC-V), +but it is ``0`` on **arm64**. + +The actual information printed and the context provided varies +significantly depending on the CPU architecture. For example: + +- On **x86**, it typically prints the instruction pointer (IP), error + code, and address that caused a page fault. +- On **PowerPC**, it may print the next instruction pointer (NIP), + link register (LR), and other relevant registers. + +When enabled, this feature is often rate-limited to prevent the kernel +log from being flooded during a crash loop. + +kprobes-optimization +==================== + +This flag enables or disables the optimization of Kprobes on certain +architectures (like x86). + +- ``0``: Kprobes optimization is turned off. +- ``1``: Kprobes optimization is turned on (default). + +For more details on Kprobes and its optimization, please refer to +Documentation/trace/kprobes.rst. + +Copyright (c) 2026, Shubham Chakraborty + +For general info and legal blurb, please look in +Documentation/admin-guide/sysctl/index.rst. + +.. See scripts/check-sysctl-docs to keep this up to date: +.. scripts/check-sysctl-docs -vtable="debug" \ +.. $(git grep -l register_sysctl_) -- cgit v1.3.1