The "dev" variable could be out of bounds. Calling
snd_seq_oss_synth_is_valid() checks that it is is a valid device
which has been opened. We check this inside set_note_event() so
this function can't succeed without a valid "dev". But we need to
do the check earlier to prevent invalid dereferences and memory
corruption.
One call tree where "dev" could be out of bounds is:
-> snd_seq_oss_oob_user()
-> snd_seq_oss_process_event()
-> extended_event()
-> note_on_event()
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
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