usb: gadget: f_uac1_legacy: validate bRequest index in generic_{set,get}_cmdgrafted

generic_set_cmd() and generic_get_cmd() use the low nibble of
ctrl->bRequest as an index into con->data[]:

    u8 cmd = (ctrl->bRequest & 0x0F);  /* 0 .. 15 */
    ...
    con->data[cmd] = value;            /* OOB when cmd >= 5 */

struct usb_audio_control (include/linux/usb/audio.h) declares data as
a 5-element array, so indices 5 through 15 write (or read) up to 44
bytes past the end of the array on the heap.

A malicious USB host can craft a class-specific SET_CUR / GET_CUR
request with an arbitrary bRequest value, triggering the out-of-bounds
access from an IRQ completion handler with no further preconditions.

Add an ARRAY_SIZE() guard to both functions.

Fixes: c47d7b09891a ("USB: audio: add USB audio class definitions")
Cc: stable <stable@kernel.org>
Reviewed-by: Weibin Liu <liuwb@xiaopeng.com>
Signed-off-by: Liu Chao <liuc63@xiaopeng.com>
Reviewed-by: Ivy Lopez <skunkolee@gmail.com>
Link: https://patch.msgid.link/20260921072551.3708191-1-liuc63@xiaopeng.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 19 insertions, 0 deletions

diff --git a/Documentation/sphinx/templates/kernel-toc.html b/Documentation/sphinx/templates/kernel-toc.html
new file mode 100644
index 000000000..b84969bd3
--- /dev/null
+++ b/Documentation/sphinx/templates/kernel-toc.html
@@ -0,0 +1,19 @@
+{# SPDX-License-Identifier: GPL-2.0 #}
+
+{# Create a local TOC the kernel way #}
+<p>
+<h3 class="kernel-toc-contents">Contents</h3>
+<input type="checkbox" class="kernel-toc-toggle" id = "kernel-toc-toggle" checked>
+<label class="kernel-toc-title" for="kernel-toc-toggle"></label>
+
+<div class="kerneltoc" id="kerneltoc">
+{{ toctree(maxdepth=3) }}
+</div>
+{# hacky script to try to position the left column #}
+<script type="text/javascript"> <!--
+  var sbar = document.getElementsByClassName("sphinxsidebar")[0];
+  let currents = document.getElementsByClassName("current")
+  if (currents.length) {
+    sbar.scrollTop = currents[currents.length - 1].offsetTop;
+  }
+  --> </script>