kernel/linux.git/include/net/sctp/command.h, branch v4.14.223

sctp: avoid running the sctp state machine recursively

2019-05-08T05:20:44+00:00

[ Upstream commit fbd019737d71e405f86549fd738f81e2ff3dd073 ] Ying triggered a call trace when doing an asconf testing: BUG: scheduling while atomic: swapper/12/0/0x10000100 Call Trace: [] dump_stack+0x19/0x1b [] __schedule_bug+0x64/0x72 [] __schedule+0x9ba/0xa00 [] __cond_resched+0x26/0x30 [] _cond_resched+0x3a/0x50 [] kmem_cache_alloc_node+0x38/0x200 [] __alloc_skb+0x5d/0x2d0 [] sctp_packet_transmit+0x610/0xa20 [sctp] [] sctp_outq_flush+0x2ce/0xc00 [sctp] [] sctp_outq_uncork+0x1c/0x20 [sctp] [] sctp_cmd_interpreter.isra.22+0xc8/0x1460 [sctp] [] sctp_do_sm+0xe1/0x350 [sctp] [] sctp_primitive_ASCONF+0x3d/0x50 [sctp] [] sctp_cmd_interpreter.isra.22+0x114/0x1460 [sctp] [] sctp_do_sm+0xe1/0x350 [sctp] [] sctp_assoc_bh_rcv+0xf4/0x1b0 [sctp] [] sctp_inq_push+0x51/0x70 [sctp] [] sctp_rcv+0xa8b/0xbd0 [sctp] As it shows, the first sctp_do_sm() running under atomic context (NET_RX softirq) invoked sctp_primitive_ASCONF() that uses GFP_KERNEL flag later, and this flag is supposed to be used in non-atomic context only. Besides, sctp_do_sm() was called recursively, which is not expected. Vlad tried to fix this recursive call in Commit c0786693404c ("sctp: Fix oops when sending queued ASCONF chunks") by introducing a new command SCTP_CMD_SEND_NEXT_ASCONF. But it didn't work as this command is still used in the first sctp_do_sm() call, and sctp_primitive_ASCONF() will be called in this command again. To avoid calling sctp_do_sm() recursively, we send the next queued ASCONF not by sctp_primitive_ASCONF(), but by sctp_sf_do_prm_asconf() in the 1st sctp_do_sm() directly. Reported-by: Ying Xu Signed-off-by: Xin Long Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: remove the typedef sctp_verb_t

2017-08-11T17:02:44+00:00

This patch is to remove the typedef sctp_verb_t, and replace with enum sctp_verb in the places where it's using this typedef. Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: remove the typedef sctp_arg_t

2017-08-11T17:02:44+00:00

This patch is to remove the typedef sctp_arg_t, and replace with union sctp_arg in the places where it's using this typedef. Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: remove the typedef sctp_cmd_seq_t

2017-08-11T17:02:44+00:00

This patch is to remove the typedef sctp_cmd_seq_t, and replace with struct sctp_cmd_seq in the places where it's using this typedef. Note that it doesn't fix many indents although it should, as sctp_disposition_t's removal would mess them up again. So better to fix them when removing sctp_disposition_t in the later patch. Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: remove the typedef sctp_cmd_t

2017-08-11T17:02:44+00:00

This patch is to remove the typedef sctp_cmd_t, and replace with enum sctp_cmd in the places where it's using this typedef. Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: remove the typedef sctp_event_timeout_t

2017-08-07T04:33:42+00:00

This patch is to remove the typedef sctp_event_timeout_t, and replace with enum sctp_event_timeout in the places where it's using this typedef. Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: remove the typedef sctp_state_t

2017-08-07T04:33:42+00:00

This patch is to remove the typedef sctp_state_t, and replace with enum sctp_state in the places where it's using this typedef. Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: remove the typedef sctp_sackhdr_t

2017-07-24T23:01:20+00:00

This patch is to remove the typedef sctp_sackhdr_t, and replace with struct sctp_sackhdr in the places where it's using this typedef. Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: remove the typedef sctp_init_chunk_t

2017-07-01T16:08:42+00:00

This patch is to remove the typedef sctp_init_chunk_t, and replace with struct sctp_init_chunk in the places where it's using this typedef. Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: handle association restarts when the socket is closed.

2014-10-06T04:21:45+00:00

Currently association restarts do not take into consideration the state of the socket. When a restart happens, the current assocation simply transitions into established state. This creates a condition where a remote system, through a the restart procedure, may create a local association that is no way reachable by user. The conditions to trigger this are as follows: 1) Remote does not acknoledge some data causing data to remain outstanding. 2) Local application calls close() on the socket. Since data is still outstanding, the association is placed in SHUTDOWN_PENDING state. However, the socket is closed. 3) The remote tries to create a new association, triggering a restart on the local system. The association moves from SHUTDOWN_PENDING to ESTABLISHED. At this point, it is no longer reachable by any socket on the local system. This patch addresses the above situation by moving the newly ESTABLISHED association into SHUTDOWN-SENT state and bundling a SHUTDOWN after the COOKIE-ACK chunk. This way, the restarted associate immidiately enters the shutdown procedure and forces the termination of the unreachable association. Reported-by: David Laight Signed-off-by: Vlad Yasevich Signed-off-by: David S. Miller