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| author | Liu Chao <liuc63@xiaopeng.com> | 2026-09-21 15:25:51 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-10-01 07:12:43 +0200 |
| commit | 9062d50e75c24dc7911be05c9b1719b3b256af15 (patch) | |
| tree | 09559f03fb76730b4f551425ce28e6e2b01db6db /arch/powerpc/lib/string.S | |
| download | linux-stable-9062d50e75c24dc7911be05c9b1719b3b256af15.tar.gz linux-stable-9062d50e75c24dc7911be05c9b1719b3b256af15.zip | |
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>
Diffstat (limited to 'arch/powerpc/lib/string.S')
| -rw-r--r-- | arch/powerpc/lib/string.S | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/arch/powerpc/lib/string.S b/arch/powerpc/lib/string.S new file mode 100644 index 000000000..c3f5e7d31 --- /dev/null +++ b/arch/powerpc/lib/string.S @@ -0,0 +1,43 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * String handling functions for PowerPC. + * + * Copyright (C) 1996 Paul Mackerras. + */ +#include <linux/export.h> +#include <asm/ppc_asm.h> +#include <asm/cache.h> + + .text + +_GLOBAL(strncmp) + PPC_LCMPI 0,r5,0 + beq- 2f + mtctr r5 + addi r5,r3,-1 + addi r4,r4,-1 + .balign IFETCH_ALIGN_BYTES +1: lbzu r3,1(r5) + cmpwi 1,r3,0 + lbzu r0,1(r4) + subf. r3,r0,r3 + beqlr 1 + bdnzt eq,1b + blr +2: li r3,0 + blr +EXPORT_SYMBOL(strncmp) + +_GLOBAL(memchr) + PPC_LCMPI 0,r5,0 + beq- 2f + mtctr r5 + addi r3,r3,-1 + .balign IFETCH_ALIGN_BYTES +1: lbzu r0,1(r3) + cmpw 0,r0,r4 + bdnzf 2,1b + beqlr +2: li r3,0 + blr +EXPORT_SYMBOL(memchr) |