3.2.95-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Takashi Iwai <[email protected]> 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 <[email protected]> Signed-off-by: Ben Hutchings <[email protected]> --- sound/core/control.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/sound/core/control.c +++ b/sound/core/control.c @@ -1084,7 +1084,7 @@ static int snd_ctl_elem_user_tlv(struct 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;
