6.5-stable review patch. If anyone has any objections, please let me know.
------------------
From: Takashi Iwai <tiwai@xxxxxxx>
commit b2ce0027d7b2905495021c5208f92043eb493146 upstream.
At the implementation of the optional proc fs in rawmidi, I forgot
that rmidi->ops itself is optional and can be NULL.
Add the proper NULL check for avoiding the Oops.
Fixes: fa030f666d24 ("ALSA: ump: Additional proc output")
Reported-and-tested-by: Mark Hills <mark@xxxxxxxx>
Closes: https://lore.kernel.org/r/ef9118c3-a2eb-d0ff-1efa-cc5fb6416bde@xxxxxxxx
Cc: <stable@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230916060725.11726-1-tiwai@xxxxxxx
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
sound/core/rawmidi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c
index ba06484ac4aa..1431cb997808 100644
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -1770,7 +1770,7 @@ static void snd_rawmidi_proc_info_read(struct snd_info_entry *entry,
if (IS_ENABLED(CONFIG_SND_UMP))
snd_iprintf(buffer, "Type: %s\n",
rawmidi_is_ump(rmidi) ? "UMP" : "Legacy");
- if (rmidi->ops->proc_read)
+ if (rmidi->ops && rmidi->ops->proc_read)
rmidi->ops->proc_read(entry, buffer);
mutex_lock(&rmidi->open_mutex);
if (rmidi->info_flags & SNDRV_RAWMIDI_INFO_OUTPUT) {
--
2.42.0
