6.5-stable review patch. If anyone has any objections, please let me know.
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From: Takashi Iwai tiwai@suse.de
commit b1757fa30ef14f254f4719bf6f7d54a4c8207216 upstream.
The allocation and initialization errors at alloc_midi_urbs() that is called at MIDI 2.0 / UMP device are supposed to be handled at the caller side by invoking free_midi_urbs(). However, free_midi_urbs() loops only for ep->num_urbs entries, and since ep->num_entries wasn't updated yet at the allocation / init error in alloc_midi_urbs(), this entry won't be released.
The intention of free_midi_urbs() is to release the whole elements, so change the loop size to NUM_URBS to scan over all elements for fixing the missed releases.
Also, the call of free_midi_urbs() is missing at snd_usb_midi_v2_open(). Although it'll be released later at reopen/close or disconnection, it's better to release immediately at the error path.
Fixes: ff49d1df79ae ("ALSA: usb-audio: USB MIDI 2.0 UMP support") Reported-by: Christophe JAILLET christophe.jaillet@wanadoo.fr Closes: https://lore.kernel.org/r/fc275ed315b9157952dcf2744ee7bdb78defdb5f.169374634... Link: https://lore.kernel.org/r/20230905054511.20502-1-tiwai@suse.de Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- sound/usb/midi2.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
--- a/sound/usb/midi2.c +++ b/sound/usb/midi2.c @@ -265,7 +265,7 @@ static void free_midi_urbs(struct snd_us
if (!ep) return; - for (i = 0; i < ep->num_urbs; ++i) { + for (i = 0; i < NUM_URBS; ++i) { ctx = &ep->urbs[i]; if (!ctx->urb) break; @@ -279,6 +279,7 @@ static void free_midi_urbs(struct snd_us }
/* allocate URBs for an EP */ +/* the callers should handle allocation errors via free_midi_urbs() */ static int alloc_midi_urbs(struct snd_usb_midi2_endpoint *ep) { struct snd_usb_midi2_urb *ctx; @@ -351,8 +352,10 @@ static int snd_usb_midi_v2_open(struct s return -EIO; if (ep->direction == STR_OUT) { err = alloc_midi_urbs(ep); - if (err) + if (err) { + free_midi_urbs(ep); return err; + } } return 0; }