From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794049715; b=oS/NLZJJKjh0/vIXXpgEZFe1DvC4npf56NDfnhHLaUKI1XDpX0AskegRBreI+oOQXYGl w4xLF3cHovATI7YMd7hXn/DzmhTNn/gxDqeWeViQQg6eQjkxRtZ/1mVzx5zF5WEuA3s4C x5mZe/I1hHaklGi5dPDBZKRPcMWxdZGinKMpiLfLBdVIK3TSmxmcqM/XFRfxX6U51ixgW xbJ53TV4OI5DKFu/AM5215tT4UnZLM/znJNUgclzFkrdPZS0IPzw357U5ZvMOFDj+Hmg7 IDrJzhdnNytOzARpCbxzHhEc+7aHeYvk9mO7B3EtPO4wixk7JyECjdUdn5O7eH9noPg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794049715; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=Ijy9ZC1Cc+DqM1bBxk6Sil3imXfabza3ibm3sRmqdIU=; b=B+hYZEjDKmvcAxivQLPh/movSFaVI+GQI3ikzjjpYrzKa+oHr2yTej0nDuGedyQuIarZ WVot+FJrvaYcHJL8kvfZb5vLB5rzdlJa6fMy+MrCRL4ulawhhZu6h4T6rxSNzzkXHbGA2 Ii3Gs1Hwtit5XR476HO4HJWQQKT5gVJ4ZphucmN73opNRW7iP6V64PYY9kyaKysYP2ZFG kRptFWCw0TthlVT7/cVTjglTXCuIz6kbWCvICLo/k9LteH0ztINW5uchR9T4tb68MYzNd lUx2ilZXyUHksnV8x8qkq+Gq4/MCQ22DQSPu64a99jJrKYAGdzWTVBs50YeC7iOiiWg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="OLZtMUj/"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 76249606A32F for ; Sat, 7 Nov 2026 11:08:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=OLZtMUj/ Received: by smtp.kernel.org (Postfix) with ESMTPSA id B2F111F0089F; Sat, 7 Nov 2026 11:08:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794049715; bh=Ijy9ZC1Cc+DqM1bBxk6Sil3imXfabza3ibm3sRmqdIU=; h=From:To:Cc:Subject:Date; b=OLZtMUj/5XMZQBX7Kjo/QT/okgNyqK7LNkzeCLsZTZ+Wgofl6ppj+VYYayKZgpjzd q939Br2yqjXVT5ooKEX2ChqxCiPIyf6CYsSOIIlc8KSSlML61YKEZaE8iwBoP66SFz /st8ImY1YxUPgBckrM8LiZuLGrKIlBJ+sucGiqd9u9Z7m5VPn/7JXMtfiRuYygkTIN EyV/s9cQxsl6/Lzkx9VelXYz+z9NHR9CiDpMcPoZ5r5ALCLLlwkk/Q6Eftek7T9sB5 4yFknM+Su+0IxsVLbJqjp41fD/CkM+q/u0l2UztOrw5gQRBdnj/skSK+rjgMUXQ5EH nOHXXod2mHLBg== From: Sasha Levin To: peter.ujfalusi@linux.intel.com, tiwai@suse.de Cc: stable@vger.kernel.org Subject: FAILED: patch "[PATCH] ALSA: compress: reject buffer geometry change on gapless next_track" failed to apply to 5.15-stable tree Date: Sat, 7 Nov 2026 06:08:33 -0500 Message-ID: <20261107060833-failed-5.15-82da1acad6fd@kernel.org> X-Mailer: git-send-email 2.53.0 X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 82da1acad6fd60b6072dd5f3383e6a55efdd2ac7 # git commit -s git send-email --to '' --in-reply-to '20261107060833-failed-5.15-82da1acad6fd@kernel.org' --subject-prefix 'PATCH 5.15.y' 'HEAD^..' Thanks, Sasha ------------------ original commit in Linus's tree ------------------ >From 82da1acad6fd60b6072dd5f3383e6a55efdd2ac7 Mon Sep 17 00:00:00 2001 From: Peter Ujfalusi Date: Mon, 19 Oct 2026 17:45:31 +0300 Subject: [PATCH] ALSA: compress: reject buffer geometry change on gapless next_track snd_compr_set_params() is invoked from the gapless next_track re-entry path, which calls snd_compr_allocate_buffer() again and lets buffer_size change while total_bytes_available and total_bytes_transferred still hold values computed for the previous buffer. snd_compr_calc_avail() then derives an avail/count value from those stale counters against the new buffer_size, and snd_compr_write_data() copy_from_user()s that many bytes into the new, potentially smaller buffer, overflowing it with user-controlled length and content. The buffer is set up once, with the initial SET_PARAMS, and neither the core nor the DSP expects it to change for a gapless track transition. Do not call snd_compr_allocate_buffer() on the next_track path and reject a request that changes the buffer geometry, so that the codec parameters that the driver receives match the buffer in use. Fixes: 9727b490e543 ("ALSA: compress: add support for gapless playback") Cc: stable@vger.kernel.org Signed-off-by: Peter Ujfalusi Link: https://patch.msgid.link/20261019144533.30665-3-peter.ujfalusi@linux.intel.com Signed-off-by: Takashi Iwai --- sound/core/compress_offload.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/sound/core/compress_offload.c b/sound/core/compress_offload.c index 50301f72579ee..d6863336f21cb 100644 --- a/sound/core/compress_offload.c +++ b/sound/core/compress_offload.c @@ -697,9 +697,19 @@ snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg) if (retval) return retval; - retval = snd_compr_allocate_buffer(stream, params); - if (retval) - return -ENOMEM; + if (stream->next_track) { + /* + * total_bytes_available/transferred still refer to the + * current buffer; its geometry must not change. + */ + if (params->buffer.fragment_size != stream->runtime->fragment_size || + params->buffer.fragments != stream->runtime->fragments) + return -EINVAL; + } else { + retval = snd_compr_allocate_buffer(stream, params); + if (retval) + return retval; + } retval = stream->ops->set_params(stream, params); if (retval) { -- 2.53.0