[ Upstream commit c305366a37441c2ac90b08711cb6f032b43672f2 ]
snd_sb_qsound_destroy() contains the calls of removing the previously
created mixer controls, but it doesn't clear the pointers. As
snd_sb_qsound_destroy() itself may be repeatedly called via ioctl,
this could lead to double-free potentially.
Fix it by clearing the struct fields properly afterwards.
Link: https://lore.kernel.org/r/20210608140540.17885-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
0e54f8ee6b