staging: rtl8723bs: fix OOB read in rtw_action_frame_parse()grafted

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 <meatuni001@gmail.com>
Link: https://patch.msgid.link/20260728125456.32359-3-meatuni001@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 174 insertions, 0 deletions

diff --git a/scripts/gendwarfksyms/examples/kabi.h b/scripts/gendwarfksyms/examples/kabi.h
new file mode 100644
index 000000000..170733a3f
--- /dev/null
+++ b/scripts/gendwarfksyms/examples/kabi.h
@@ -0,0 +1,174 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2024 Google LLC
+ *
+ * Example macros for maintaining kABI stability.
+ *
+ * This file is based on android_kabi.h, which has the following notice:
+ *
+ * Heavily influenced by rh_kabi.h which came from the RHEL/CENTOS kernel
+ * and was:
+ *	Copyright (c) 2014 Don Zickus
+ *	Copyright (c) 2015-2018 Jiri Benc
+ *	Copyright (c) 2015 Sabrina Dubroca, Hannes Frederic Sowa
+ *	Copyright (c) 2016-2018 Prarit Bhargava
+ *	Copyright (c) 2017 Paolo Abeni, Larry Woodman
+ */
+
+#ifndef __KABI_H__
+#define __KABI_H__
+
+/* Kernel macros for userspace testing. */
+#ifndef __aligned
+#define __aligned(x) __attribute__((__aligned__(x)))
+#endif
+#ifndef __used
+#define __used __attribute__((__used__))
+#endif
+#ifndef __section
+#define __section(section) __attribute__((__section__(section)))
+#endif
+#ifndef __PASTE
+#define ___PASTE(a, b) a##b
+#define __PASTE(a, b) ___PASTE(a, b)
+#endif
+#ifndef __stringify
+#define __stringify_1(x...) #x
+#define __stringify(x...) __stringify_1(x)
+#endif
+
+#define ___KABI_RULE(hint, target, value)                            \
+	static const char __PASTE(__gendwarfksyms_rule_,             \
+				  __COUNTER__)[] __used __aligned(1) \
+		__section(".discard.gendwarfksyms.kabi_rules") =     \
+			"1\0" #hint "\0" target "\0" value
+
+#define __KABI_RULE(hint, target, value) \
+	___KABI_RULE(hint, #target, #value)
+
+#define __KABI_NORMAL_SIZE_ALIGN(_orig, _new)                                             \
+	union {                                                                           \
+		_Static_assert(                                                           \
+			sizeof(struct { _new; }) <= sizeof(struct { _orig; }),            \
+			__FILE__ ":" __stringify(__LINE__) ": " __stringify(              \
+				_new) " is larger than " __stringify(_orig));             \
+		_Static_assert(                                                           \
+			__alignof__(struct { _new; }) <=                                  \
+				__alignof__(struct { _orig; }),                           \
+			__FILE__ ":" __stringify(__LINE__) ": " __stringify(              \
+				_orig) " is not aligned the same as " __stringify(_new)); \
+	}
+
+#define __KABI_REPLACE(_orig, _new)                    \
+	union {                                        \
+		_new;                                  \
+		struct {                               \
+			_orig;                         \
+		};                                     \
+		__KABI_NORMAL_SIZE_ALIGN(_orig, _new); \
+	}
+
+/*
+ * KABI_DECLONLY(fqn)
+ *   Treat the struct/union/enum fqn as a declaration, i.e. even if
+ *   a definition is available, don't expand the contents.
+ */
+#define KABI_DECLONLY(fqn) __KABI_RULE(declonly, fqn, )
+
+/*
+ * KABI_ENUMERATOR_IGNORE(fqn, field)
+ *   When expanding enum fqn, skip the provided field. This makes it
+ *   possible to hide added enum fields from versioning.
+ */
+#define KABI_ENUMERATOR_IGNORE(fqn, field) \
+	__KABI_RULE(enumerator_ignore, fqn field, )
+
+/*
+ * KABI_ENUMERATOR_VALUE(fqn, field, value)
+ *   When expanding enum fqn, use the provided value for the
+ *   specified field. This makes it possible to override enumerator
+ *   values when calculating versions.
+ */
+#define KABI_ENUMERATOR_VALUE(fqn, field, value) \
+	__KABI_RULE(enumerator_value, fqn field, value)
+
+/*
+ * KABI_BYTE_SIZE(fqn, value)
+ *   Set the byte_size attribute for the struct/union/enum fqn to
+ *   value bytes.
+ */
+#define KABI_BYTE_SIZE(fqn, value) __KABI_RULE(byte_size, fqn, value)
+
+/*
+ * KABI_TYPE_STRING(type, str)
+ *   For the given type, override the type string used in symtypes
+ *   output and version calculation with str.
+ */
+#define KABI_TYPE_STRING(type, str) ___KABI_RULE(type_string, type, str)
+
+/*
+ * KABI_RESERVE
+ *   Reserve some "padding" in a structure for use by LTS backports.
+ *   This is normally placed at the end of a structure.
+ *   number: the "number" of the padding variable in the structure.  Start with
+ *   1 and go up.
+ */
+#define KABI_RESERVE(n) unsigned long __kabi_reserved##n
+
+/*
+ * KABI_RESERVE_ARRAY
+ *   Same as _BACKPORT_RESERVE but allocates an array with the specified
+ *   size in bytes.
+ */
+#define KABI_RESERVE_ARRAY(n, s) \
+	unsigned char __aligned(8) __kabi_reserved##n[s]
+
+/*
+ * KABI_IGNORE
+ *   Add a new field that's ignored in versioning.
+ */
+#define KABI_IGNORE(n, _new)                     \
+	union {                                  \
+		_new;                            \
+		unsigned char __kabi_ignored##n; \
+	}
+
+/*
+ * KABI_REPLACE
+ *   Replace a field with a compatible new field.
+ */
+#define KABI_REPLACE(_oldtype, _oldname, _new) \
+	__KABI_REPLACE(_oldtype __kabi_renamed##_oldname, struct { _new; })
+
+/*
+ * KABI_USE(number, _new)
+ *   Use a previous padding entry that was defined with KABI_RESERVE
+ *   number: the previous "number" of the padding variable
+ *   _new: the variable to use now instead of the padding variable
+ */
+#define KABI_USE(number, _new) __KABI_REPLACE(KABI_RESERVE(number), _new)
+
+/*
+ * KABI_USE2(number, _new1, _new2)
+ *   Use a previous padding entry that was defined with KABI_RESERVE for
+ *   two new variables that fit into 64 bits.  This is good for when you do not
+ *   want to "burn" a 64bit padding variable for a smaller variable size if not
+ *   needed.
+ */
+#define KABI_USE2(number, _new1, _new2)        \
+	__KABI_REPLACE(                        \
+		KABI_RESERVE(number), struct { \
+			_new1;                 \
+			_new2;                 \
+		})
+/*
+ * KABI_USE_ARRAY(number, bytes, _new)
+ *   Use a previous padding entry that was defined with KABI_RESERVE_ARRAY
+ *   number: the previous "number" of the padding variable
+ *   bytes: the size in bytes reserved for the array
+ *   _new: the variable to use now instead of the padding variable
+ */
+#define KABI_USE_ARRAY(number, bytes, _new) \
+	__KABI_REPLACE(KABI_RESERVE_ARRAY(number, bytes), _new)
+
+#endif /* __KABI_H__ */