From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EC9AC4657D0; Tue, 16 Jun 2026 17:18:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781630297; cv=none; b=Fb3KCJA7tD8qkOwA65ciO4T5ATOOfiB7l5P7PHvLEFNG+GNKXkiLXaUwVWI6YyuS9cuWlAZZsO4CpWvJVCw5Iz+YUzqCgJFrM42Rw+Wa8J3YzMJXeAtEWEY/k/LZB3nZgNMmFUty34ZozQ+mTFvtZ2tjfVIxuLN7eIUMnaWLAHI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781630297; c=relaxed/simple; bh=cFqaA0iGsj57JQv//R+7D/nvXHqA0TIFk2vLKCu1f/0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=lPpHmaEFH7NT318n2ZV8Y3rXRqhAcahp9SExd31I36DVBZjzr7fR7ZM4TL745gqZW8sqqgKCLe1qsw0LkCo8DFiqKXCwcbpwFmW6sS2y4VkiOWgmgnYsIMFXBpFp+kQ9NE3A9PwCNKDOrpWDn92uU6nOUou9cLOa2IMuOIfJwTs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=DNKovTCg; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="DNKovTCg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EECE41F000E9; Tue, 16 Jun 2026 17:18:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781630296; bh=1fiirbpAbdY6izSbk3cTrb1qTO0o1Ya80Vpf1XqSUAs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=DNKovTCgfJ+9yNPN3B8Gb7bdp95/qL1F+N/X1Ic8rjm1/VxqgFMMoMNzjsmQa9t9U +YI6Vhz50SspgaQpcg2YBrUufJbd8EpMDExVLh2Fx1lzp+CFzMK2drnoiprfiWHOb0 kkSx2TtL4pXeDXNGs+1VADhq7fRp0OxSzS9KBTEY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?C=C3=A1ssio=20Gabriel?= , Takashi Sakamoto , Takashi Iwai , Sasha Levin Subject: [PATCH 6.6 415/452] ALSA: firewire-motu: Protect register DSP event queue positions Date: Tue, 16 Jun 2026 20:30:42 +0530 Message-ID: <20260616145138.581454539@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145117.796205997@linuxfoundation.org> References: <20260616145117.796205997@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Cássio Gabriel [ Upstream commit 98fb1c1bb11e29eb609b7200a25e136e05aa4498 ] The register DSP event queue is updated under parser->lock, but snd_motu_register_dsp_message_parser_count_event() reads pull_pos and push_pos without the lock. snd_motu_register_dsp_message_parser_copy_event() also reads both queue positions before taking the lock. Protect these accesses with parser->lock as well. This keeps the hwdep poll/read path consistent with the producer side and with the cached meter/parameter accessors. Fixes: 634ec0b2906e ("ALSA: firewire-motu: notify event for parameter change in register DSP model") Cc: stable@vger.kernel.org Signed-off-by: Cássio Gabriel Reviewed-by: Takashi Sakamoto Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20260521-alsa-firewire-motu-event-locking-v1-1-708e1c2b5e56@gmail.com [ converted copy_event() from manual spin_lock_irqsave/spin_unlock_irqrestore to guard(spinlock_irqsave) ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- sound/firewire/motu/motu-register-dsp-message-parser.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) --- a/sound/firewire/motu/motu-register-dsp-message-parser.c +++ b/sound/firewire/motu/motu-register-dsp-message-parser.c @@ -393,6 +393,8 @@ unsigned int snd_motu_register_dsp_messa { struct msg_parser *parser = motu->message_parser; + guard(spinlock_irqsave)(&parser->lock); + if (parser->pull_pos > parser->push_pos) return EVENT_QUEUE_SIZE - parser->pull_pos + parser->push_pos; else @@ -402,14 +404,14 @@ unsigned int snd_motu_register_dsp_messa bool snd_motu_register_dsp_message_parser_copy_event(struct snd_motu *motu, u32 *event) { struct msg_parser *parser = motu->message_parser; - unsigned int pos = parser->pull_pos; - unsigned long flags; + unsigned int pos; - if (pos == parser->push_pos) - return false; + guard(spinlock_irqsave)(&parser->lock); - spin_lock_irqsave(&parser->lock, flags); + if (parser->pull_pos == parser->push_pos) + return false; + pos = parser->pull_pos; *event = parser->event_queue[pos]; ++pos; @@ -417,7 +419,5 @@ bool snd_motu_register_dsp_message_parse pos = 0; parser->pull_pos = pos; - spin_unlock_irqrestore(&parser->lock, flags); - return true; }