Re: [PATCH] [v2] ALSA: core: fix buffer overflow in test_format_fill_silence()

From: Takashi Iwai
Date: Mon Feb 19 2024 - 03:24:14 EST


On Sat, 17 Feb 2024 11:42:38 +0100,
Arnd Bergmann wrote:
>
> From: Arnd Bergmann <arnd@xxxxxxxx>
>
> KASAN caught a buffer overflow with the hardcoded 2048 byte buffer
> size, when 2080 bytes are written to it:
>
> BUG: KASAN: slab-out-of-bounds in snd_pcm_format_set_silence+0x3bc/0x3e4
> Write of size 8 at addr ffff0000c8149800 by task kunit_try_catch/1297
>
> CPU: 0 PID: 1297 Comm: kunit_try_catch Tainted: G N 6.8.0-rc4-next-20240216 #1
> Hardware name: linux,dummy-virt (DT)
> Call trace:
> kasan_report+0x78/0xc0
> __asan_report_store_n_noabort+0x1c/0x28
> snd_pcm_format_set_silence+0x3bc/0x3e4
> _test_fill_silence+0xdc/0x298
> test_format_fill_silence+0x110/0x228
> kunit_try_run_case+0x144/0x3bc
> kunit_generic_run_threadfn_adapter+0x50/0x94
> kthread+0x330/0x3e8
> ret_from_fork+0x10/0x20
>
> Allocated by task 1297:
> __kmalloc+0x17c/0x2f0
> kunit_kmalloc_array+0x2c/0x78
> test_format_fill_silence+0xcc/0x228
> kunit_try_run_case+0x144/0x3bc
> kunit_generic_run_threadfn_adapter+0x50/0x94
> kthread+0x330/0x3e8
> ret_from_fork+0x10/0x20
>
> Replace the incorrect size with the correct length of 260 64-bit samples.
>
> Reported-by: Naresh Kamboju <naresh.kamboju@xxxxxxxxxx>
> Suggested-by: Ivan Orlov <ivan.orlov0322@xxxxxxxxx>
> Fixes: 3e39acf56ede ("ALSA: core: Add sound core KUnit test")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
> v2: use a named constant as suggested by Ivan Orlov

Thanks, applied now.


Takashi