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=1794047813; b=sUNazHwySvx633FXt+DY+PvXP77mssXdH1qKYi4K4Jj2rtcKEarCkaU8b4BXNBfhUYaL edYr04GdC4CWITF8eP6WphEyJma3pWqRZdkp/zUiiiveLlZWaRy9v2hmNpEDnUhEPkD5W K4GRKrd7yEKvLVfWmwQxJttqriaCTnUOwVm0SxvrbYXaj45q+KZe2KsfHYPZehFLowbSq QJDRJ76lnQ6TRqRf+DIe5V9WL/+3nsWlc3JYXSI60cLL3ef8dkWRVcDxA9jy8mAzYP80m LJdA6zey5E61o4rEqORMM04u6LIsBO8XeEhw36OIaW0P3ZZWDdcizbxcGCQpcUJ/wIA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794047813; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=nSH67wWyhxtaUOJLOUOCQxtchhTWWRlbILutZPr4Ks4=; b=AU4qsAqgcJKcZiEzDeuHhwuyXcU+zlfEgngK55cHEl4Giz0O14wjhwNs/ycCkiU9lsOA ecES3pEvdN5wT9NXcIvXq9om6Y3achweVprXCh04Z1nornFcaa8twnte4slbc7fvE0n7y SIdalq6VrEf8h07b1K+cLUxSAUlV5ORvkKaPeQXoYwJGeh3g3CRQYh8rhzvhPKUugBATz a3pKijo6iI8GK8r1C1EietB+yd8VKZa2nnOjESYovUphwBstFPJvupz2/c1tOdCgusv8S DGfifUrV3tUzZbXag/xWncJJkKKLfsPkjduC6HnAsKE2wy6GIKvKNbwlc5ta5R8ZSyw== 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=YFaMqPnf; 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 BEE40606A32C for ; Sat, 7 Nov 2026 10:36:52 +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=YFaMqPnf Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3884A1F0089F; Sat, 7 Nov 2026 10:36:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794047812; bh=nSH67wWyhxtaUOJLOUOCQxtchhTWWRlbILutZPr4Ks4=; h=From:To:Cc:Subject:Date; b=YFaMqPnfWu93VhROn6wIMMygGTrL3prg+NVsz7h1uSgVC6zuv02Fg8//iqeAtJQ+H 2+83JzxhRf1OudWDUTEJhTigeJq6mG44iQ6sQBWy4hHBY03iHi3ZoHqsIfNp+GDvLV 0e0Xq2OpwDGLfEbJrIl51hN7mDNUQp4Ky1verjEPOAQZtZ9g4uml5coRiQbbhb5bo7 5TPBYUi3qOqbVBi0Lwe5dfq0MSBzQB7wekhI1tRyfPP4t3NlfF/2hc5Z8xilb56ASR kELmhtWlUOD6JXZ+2WLzlb9Ms5Y9y+BfL9Um1Q1laYojOmd/XeKMr/spHLkt3hfhKO +ymHjQLhbek4g== 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 6.6-stable tree Date: Sat, 7 Nov 2026 05:36:51 -0500 Message-ID: <20261107053651-failed-6.6-82da1acad6fd@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 6.6-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-6.6.y git checkout FETCH_HEAD git cherry-pick -x 82da1acad6fd60b6072dd5f3383e6a55efdd2ac7 # git commit -s git send-email --to '' --in-reply-to '20261107053651-failed-6.6-82da1acad6fd@kernel.org' --subject-prefix 'PATCH 6.6.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