sctp: leave the err path free in sctp_stream_init to sctp_stream_free
A NULL pointer dereference was reported by Wei Chen: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:__list_del_entry_valid+0x26/0x80 Call Trace: <TASK> sctp_sched_dequeue_common+0x1c/0x90 sctp_sched_prio_dequeue+0x67/0x80 __sctp_outq_teardown+0x299/0x380 sctp_outq_free+0x15/0x20 sctp_association_free+0xc3/0x440 sctp_do_sm+0x1ca7/0x2210 sctp_assoc_bh_rcv+0x1f6/0x340 This happens when calling sctp_sendmsg without connecting to server first. In this case, a data chunk already queues up in send queue of client side when processing the INIT_ACK from server in sctp_process_init() where it calls sctp_stream_init() to alloc stream_in. If it fails to alloc stream_in all stream_out will be freed in sctp_stream_init's err path. Then in the asoc freeing it will crash when dequeuing this data chunk as stream_out is missing. As we can't free stream out before dequeuing all data from send queue, and this patch is to fix it by moving the err path stream_out/in freeing in sctp_stream_init() to sctp_stream_free() which is eventually called when freeing the asoc in sctp_association_free(). This fix also makes the code in sctp_process_init() more clear. Note that in sctp_association_init() when it fails in sctp_stream_init(), sctp_association_free() will not be called, and in that case it should go to 'stream_free' err path to free stream instead of 'fail_init'. Fixes: 5bbbbe32 ("sctp: introduce stream scheduler foundations") Reported-by:Wei Chen <harperchen1110@gmail.com> Signed-off-by: