From ac0d71ee534e67c7e53439e8e9cb45ed40731660 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Wed, 29 May 2024 18:47:16 +0200 Subject: ALSA: ump: Don't accept an invalid UMP protocol number When a UMP Stream Configuration message is received, the driver tries to switch the protocol, but there was no sanity check of the protocol, hence it can pass an invalid value. Add the check and bail out if a wrong value is passed. Fixes: a79807683781 ("ALSA: ump: Add helper to change MIDI protocol") Cc: Link: https://lore.kernel.org/r/20240529164723.18309-1-tiwai@suse.de Signed-off-by: Takashi Iwai --- sound/core/ump.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'sound/core/ump.c') diff --git a/sound/core/ump.c b/sound/core/ump.c index fd6a68a54278..117c7ecc4856 100644 --- a/sound/core/ump.c +++ b/sound/core/ump.c @@ -685,10 +685,17 @@ static void seq_notify_protocol(struct snd_ump_endpoint *ump) */ int snd_ump_switch_protocol(struct snd_ump_endpoint *ump, unsigned int protocol) { + unsigned int type; + protocol &= ump->info.protocol_caps; if (protocol == ump->info.protocol) return 0; + type = protocol & SNDRV_UMP_EP_INFO_PROTO_MIDI_MASK; + if (type != SNDRV_UMP_EP_INFO_PROTO_MIDI1 && + type != SNDRV_UMP_EP_INFO_PROTO_MIDI2) + return 0; + ump->info.protocol = protocol; ump_dbg(ump, "New protocol = %x (caps = %x)\n", protocol, ump->info.protocol_caps); -- cgit v1.2.3 From bc42ca002d5d211f9c57334b9b4c25ddb0b4ec35 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Wed, 29 May 2024 18:47:17 +0200 Subject: ALSA: ump: Set default protocol when not given explicitly When an inquiry of the current protocol via UMP Stream Configuration message fails by some reason, we may leave the current protocol undefined, which may lead to unexpected behavior. Better to assume a valid protocol found in the protocol capability bits instead. For a device that doesn't support the UMP v1.2 feature, it won't reach to this code path, and USB MIDI GTB descriptor would be used for determining the protocol, instead. Link: https://lore.kernel.org/r/20240529164723.18309-2-tiwai@suse.de Signed-off-by: Takashi Iwai --- sound/core/ump.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'sound/core/ump.c') diff --git a/sound/core/ump.c b/sound/core/ump.c index 117c7ecc4856..3f61220c23b4 100644 --- a/sound/core/ump.c +++ b/sound/core/ump.c @@ -967,6 +967,14 @@ int snd_ump_parse_endpoint(struct snd_ump_endpoint *ump) if (err < 0) ump_dbg(ump, "Unable to get UMP EP stream config\n"); + /* If no protocol is set by some reason, assume the valid one */ + if (!(ump->info.protocol & SNDRV_UMP_EP_INFO_PROTO_MIDI_MASK)) { + if (ump->info.protocol_caps & SNDRV_UMP_EP_INFO_PROTO_MIDI2) + ump->info.protocol |= SNDRV_UMP_EP_INFO_PROTO_MIDI2; + else if (ump->info.protocol_caps & SNDRV_UMP_EP_INFO_PROTO_MIDI1) + ump->info.protocol |= SNDRV_UMP_EP_INFO_PROTO_MIDI1; + } + /* Query and create blocks from Function Blocks */ for (blk = 0; blk < ump->info.num_blocks; blk++) { err = create_block_from_fb_info(ump, blk); -- cgit v1.2.3