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

Summary

In the Linux kernel, the following vulnerability has been resolved: usb: gadget: f_uac1_legacy: validate bRequest index in generic_{set,get}_cmd 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.

Timeline

1. Oct 18, 2026, 3:48 PM UTCCVE published
2. Oct 21, 2026, 12:56 PM UTCRecord last updated

Affected versions

• Linux Linux

  From c47d7b09891abb4f8b222317c89c7469bed8db3a · fixed in da841c1511a6160b8bc6bb7b7c6d4c9fb76fb51e; From c47d7b09891abb4f8b222317c89c7469bed8db3a · fixed in 36f3f009049bc91e14dc856007932473318d12f8; From c47d7b09891abb4f8b222317c89c7469bed8db3a · fixed in 8c611876c002d712ae5f246af5188432c708f79d; From c47d7b09891abb4f8b222317c89c7469bed8db3a · fixed in 697cfe6e53b66cda196d6f8833b0ee97fefd0a8a; From c47d7b09891abb4f8b222317c89c7469bed8db3a · fixed in 9062d50e75c24dc7911be05c9b1719b3b256af15

• Linux Linux

  2.6.31

• KernelLinux

  From 2.6.31 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.113; From 6.13.0 · fixed in 6.18.56; From 6.19.0 · fixed in 7.2.10

References 5