[ Upstream commit 796e119e9b ]
Without CONFIG_SND_DYNAMIC_MINORS, ALSA reserves only two fixed minors
for compress devices on each card: comprD0 and comprD1.
snd_find_free_minor() currently computes the compress minor as
type + dev without validating dev first, so device numbers greater than
1 spill into the HWDEP minor range instead of failing registration.
ASoC passes rtd->id to snd_compress_new(), so this can happen on real
non-dynamic-minor builds.
Add a dedicated fixed-minor check for SNDRV_DEVICE_TYPE_COMPRESS in
snd_find_free_minor() and reject out-of-range device numbers with
-EINVAL before constructing the minor.
Also remove the stale TODO in compress_offload.c that still claims
multiple compress nodes are missing.
Fixes: 3eafc959b3 ("ALSA: core: add support for compressed devices")
Signed-off-by: Cássio Gabriel <cassiogabrielcontato@gmail.com>
Link: https://patch.msgid.link/20260325-alsa-compress-static-minors-v1-1-0628573bee1c@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
22d0e2a9f0