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, 208 insertions, 0 deletions

diff --git a/Documentation/netlink/specs/nlctrl.yaml b/Documentation/netlink/specs/nlctrl.yaml
new file mode 100644
index 000000000..8b4472a6a
--- /dev/null
+++ b/Documentation/netlink/specs/nlctrl.yaml
@@ -0,0 +1,208 @@
+# SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)
+---
+name: nlctrl
+protocol: genetlink-legacy
+uapi-header: linux/genetlink.h
+
+doc: |
+  genetlink meta-family that exposes information about all genetlink
+  families registered in the kernel (including itself).
+
+definitions:
+  -
+    name: op-flags
+    type: flags
+    enum-name:
+    entries:
+      - admin-perm
+      - cmd-cap-do
+      - cmd-cap-dump
+      - cmd-cap-haspol
+      - uns-admin-perm
+  -
+    name: attr-type
+    enum-name: netlink-attribute-type
+    type: enum
+    entries:
+      - invalid
+      - flag
+      - u8
+      - u16
+      - u32
+      - u64
+      - s8
+      - s16
+      - s32
+      - s64
+      - binary
+      - string
+      - nul-string
+      - nested
+      - nested-array
+      - bitfield32
+      - sint
+      - uint
+
+attribute-sets:
+  -
+    name: ctrl-attrs
+    name-prefix: ctrl-attr-
+    attributes:
+      -
+        name: family-id
+        type: u16
+      -
+        name: family-name
+        type: string
+      -
+        name: version
+        type: u32
+      -
+        name: hdrsize
+        type: u32
+      -
+        name: maxattr
+        type: u32
+      -
+        name: ops
+        type: indexed-array
+        sub-type: nest
+        nested-attributes: op-attrs
+      -
+        name: mcast-groups
+        type: indexed-array
+        sub-type: nest
+        nested-attributes: mcast-group-attrs
+      -
+        name: policy
+        type: nest-type-value
+        type-value: [policy-id, attr-id]
+        nested-attributes: policy-attrs
+      -
+        name: op-policy
+        type: nest-type-value
+        type-value: [op-id]
+        nested-attributes: op-policy-attrs
+      -
+        name: op
+        type: u32
+  -
+    name: mcast-group-attrs
+    name-prefix: ctrl-attr-mcast-grp-
+    enum-name:
+    attributes:
+      -
+        name: name
+        type: string
+      -
+        name: id
+        type: u32
+  -
+    name: op-attrs
+    name-prefix: ctrl-attr-op-
+    enum-name:
+    attributes:
+      -
+        name: id
+        type: u32
+      -
+        name: flags
+        type: u32
+        enum: op-flags
+        enum-as-flags: true
+  -
+    name: policy-attrs
+    name-prefix: nl-policy-type-attr-
+    enum-name:
+    attributes:
+      -
+        name: type
+        type: u32
+        enum: attr-type
+      -
+        name: min-value-s
+        type: s64
+      -
+        name: max-value-s
+        type: s64
+      -
+        name: min-value-u
+        type: u64
+      -
+        name: max-value-u
+        type: u64
+      -
+        name: min-length
+        type: u32
+      -
+        name: max-length
+        type: u32
+      -
+        name: policy-idx
+        type: u32
+      -
+        name: policy-maxtype
+        type: u32
+      -
+        name: bitfield32-mask
+        type: u32
+      -
+        name: mask
+        type: u64
+      -
+        name: pad
+        type: pad
+  -
+    name: op-policy-attrs
+    name-prefix: ctrl-attr-policy-
+    enum-name:
+    attributes:
+      -
+        name: do
+        type: u32
+      -
+        name: dump
+        type: u32
+
+operations:
+  enum-model: directional
+  name-prefix: ctrl-cmd-
+  list:
+    -
+      name: getfamily
+      doc: Get / dump genetlink families
+      attribute-set: ctrl-attrs
+      do:
+        request:
+          value: 3
+          attributes:
+            - family-name
+        reply: &all-attrs
+          value: 1
+          attributes:
+            - family-id
+            - family-name
+            - hdrsize
+            - maxattr
+            - mcast-groups
+            - ops
+            - version
+      dump:
+        reply: *all-attrs
+    -
+      name: getpolicy
+      doc: Get / dump genetlink policies
+      attribute-set: ctrl-attrs
+      dump:
+        request:
+          value: 10
+          attributes:
+            - family-name
+            - family-id
+            - op
+        reply:
+          value: 10
+          attributes:
+            - family-id
+            - op-policy
+            - policy