diff options
| author | Takashi Iwai <tiwai@suse.de> | 2017-08-22 09:15:13 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-08-30 11:26:31 +0300 |
| commit | ba6b08b62f0cc989a9b9465bf5bdca2b68ba43d4 (patch) | |
| tree | fe340b7f39fb6ba223cb5acb52e0fb112d31fa9c | |
| parent | 1157dcda136aa1ad408f7dbc4aa385639ee783e2 (diff) | |
| download | linux-ba6b08b62f0cc989a9b9465bf5bdca2b68ba43d4.tar.xz | |
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 c109b82eef4b..7b43b0f74b84 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -1157,7 +1157,7 @@ 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; |