From: Junrui Luo Date: Tue, 9 Dec 2025 05:16:41 +0000 (+0800) Subject: ALSA: firewire-motu: add bounds check in put_user loop for DSP events X-Git-Tag: v6.19-rc1~20^2~4 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=298e753880b6ea99ac30df34959a7a03b0878eed;p=thirdparty%2Flinux.git ALSA: firewire-motu: add bounds check in put_user loop for DSP events In the DSP event handling code, a put_user() loop copies event data. When the user buffer size is not aligned to 4 bytes, it could overwrite beyond the buffer boundary. Fix by adding a bounds check before put_user(). Suggested-by: Takashi Iwai Fixes: 634ec0b2906e ("ALSA: firewire-motu: notify event for parameter change in register DSP model") Signed-off-by: Junrui Luo Link: https://patch.msgid.link/SYBPR01MB788112C72AF8A1C8C448B4B8AFA3A@SYBPR01MB7881.ausprd01.prod.outlook.com Signed-off-by: Takashi Iwai --- diff --git a/sound/firewire/motu/motu-hwdep.c b/sound/firewire/motu/motu-hwdep.c index 6675b23aad69..89dc436a0652 100644 --- a/sound/firewire/motu/motu-hwdep.c +++ b/sound/firewire/motu/motu-hwdep.c @@ -75,7 +75,7 @@ static long hwdep_read(struct snd_hwdep *hwdep, char __user *buf, long count, while (consumed < count && snd_motu_register_dsp_message_parser_copy_event(motu, &ev)) { ptr = (u32 __user *)(buf + consumed); - if (put_user(ev, ptr)) + if (consumed + sizeof(ev) > count || put_user(ev, ptr)) return -EFAULT; consumed += sizeof(ev); }