diff options
| author | Takashi Iwai <tiwai@suse.de> | 2017-08-22 08:15:13 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-08-30 10:19:22 +0200 |
| commit | 099e57fcb03fb46ec707c9627ebc5e8b6f1ffcdc (patch) | |
| tree | 7efc858b827fad4670fa7929c72fb3cf3d648d5f | |
| parent | 07051c1754775c95306ef75730efbaa321a97523 (diff) | |
ALSA: core: Fix unexpected error at replacing user TLV
commit 88c54cdf61f508ebcf8da2d819f5dfc03e954d1d upstream.
When user tries to replace the user-defined control TLV, the kernel
checks the change of its content via memcmp(). The problem is that
the kernel passes the return value from memcmp() as is. memcmp()
gives a non-zero negative value depending on the comparison result,
and this shall be recognized as an error code.
The patch covers that corner-case, return 1 properly for the changed
TLV.
Fixes: 8aa9b586e420 ("[ALSA] Control API - more robust TLV implementation")
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | sound/core/control.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/sound/core/control.c b/sound/core/control.c index b4fe9b002512..bd01d492f46a 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -1126,7 +1126,7 @@ static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kcontrol, mutex_lock(&ue->card->user_ctl_lock); change = ue->tlv_data_size != size; if (!change) - change = memcmp(ue->tlv_data, new_data, size); + change = memcmp(ue->tlv_data, new_data, size) != 0; kfree(ue->tlv_data); ue->tlv_data = new_data; ue->tlv_data_size = size; |