ASoC: soc-compress: prevent the potentially use of null pointer
There is one call trace that snd_soc_register_card() ->snd_soc_bind_card()->soc_init_pcm_runtime() ->snd_soc_dai_compress_new()->snd_soc_new_compress(). In the trace the 'codec_dai' transfers from card->dai_link, and we can see from the snd_soc_add_pcm_runtime() in snd_soc_bind_card() that, if value of card->dai_link->num_codecs is 0, then 'codec_dai' could be null pointer caused by index out of bound in 'asoc_rtd_to_codec(rtd, 0)'. And snd_soc_register_card() is called by various platforms. Therefore, it is better to add the check in the case of misusing. And because 'cpu_dai' has already checked in soc_init_pcm_runtime(), there is no need to check again. Adding the check as follow, then if 'codec_dai' is null, snd_soc_new_compress() will not pass through the check 'if (playback + capture != 1)', avoiding the leftover use of 'codec_dai'. Fixes: 467fece8 ("ASoC: soc-dai: move snd_soc_dai_stream_valid() to soc-dai.c") Signed-off-by: NJiasheng Jiang <jiasheng@iscas.ac.cn> Reported-by: Nkernel test robot <lkp@intel.com> Reported-by: NDan Carpenter <dan.carpenter@oracle.com> Link: https://lore.kernel.org/r/1634285633-529368-1-git-send-email-jiasheng@iscas.ac.cnSigned-off-by: NMark Brown <broonie@kernel.org>
Showing
想要评论请 注册 或 登录