From c0786693404cffd80ca3cb6e75ee7b35186b2825 Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Wed, 28 Apr 2010 08:47:22 +0000 Subject: [PATCH] sctp: Fix oops when sending queued ASCONF chunks When we finish processing ASCONF_ACK chunk, we try to send the next queued ASCONF. This action runs the sctp state machine recursively and it's not prepared to do so. kernel BUG at kernel/timer.c:790! invalid opcode: 0000 [#1] SMP last sysfs file: /sys/module/ipv6/initstate Modules linked in: sha256_generic sctp libcrc32c ipv6 dm_multipath uinput 8139too i2c_piix4 8139cp mii i2c_core pcspkr virtio_net joydev floppy virtio_blk virtio_pci [last unloaded: scsi_wait_scan] Pid: 0, comm: swapper Not tainted 2.6.34-rc4 #15 /Bochs EIP: 0060:[] EFLAGS: 00010286 CPU: 0 EIP is at add_timer+0xd/0x1b EAX: cecbab14 EBX: 000000f0 ECX: c0957b1c EDX: 03595cf4 ESI: cecba800 EDI: cf276f00 EBP: c0957aa0 ESP: c0957aa0 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 Process swapper (pid: 0, ti=c0956000 task=c0988ba0 task.ti=c0956000) Stack: c0957ae0 d1851214 c0ab62e4 c0ab5f26 0500ffff 00000004 00000005 00000004 <0> 00000000 d18694fd 00000004 1666b892 cecba800 cecba800 c0957b14 00000004 <0> c0957b94 d1851b11 ceda8b00 cecba800 cf276f00 00000001 c0957b14 000000d0 Call Trace: [] ? sctp_side_effects+0x607/0xdfc [sctp] [] ? sctp_do_sm+0x108/0x159 [sctp] [] ? sctp_pname+0x0/0x1d [sctp] [] ? sctp_primitive_ASCONF+0x36/0x3b [sctp] [] ? sctp_process_asconf_ack+0x2a4/0x2d3 [sctp] [] ? sctp_sf_do_asconf_ack+0x1dd/0x2b4 [sctp] [] ? sctp_do_sm+0xb8/0x159 [sctp] [] ? sctp_cname+0x0/0x52 [sctp] [] ? sctp_assoc_bh_rcv+0xac/0xe1 [sctp] [] ? sctp_inq_push+0x2d/0x30 [sctp] [] ? sctp_rcv+0x797/0x82e [sctp] Tested-by: Wei Yongjun Signed-off-by: Yuansong Qiao Signed-off-by: Shuaijun Zhang Signed-off-by: Vlad Yasevich Signed-off-by: David S. Miller --- include/net/sctp/command.h | 1 + net/sctp/sm_make_chunk.c | 15 --------------- net/sctp/sm_sideeffect.c | 26 ++++++++++++++++++++++++++ net/sctp/sm_statefuns.c | 8 +++++++- 4 files changed, 34 insertions(+), 16 deletions(-) diff --git a/include/net/sctp/command.h b/include/net/sctp/command.h index 8be5135ff7aa..2c55a7ea20af 100644 --- a/include/net/sctp/command.h +++ b/include/net/sctp/command.h @@ -107,6 +107,7 @@ typedef enum { SCTP_CMD_T1_RETRAN, /* Mark for retransmission after T1 timeout */ SCTP_CMD_UPDATE_INITTAG, /* Update peer inittag */ SCTP_CMD_SEND_MSG, /* Send the whole use message */ + SCTP_CMD_SEND_NEXT_ASCONF, /* Send the next ASCONF after ACK */ SCTP_CMD_LAST } sctp_verb_t; diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c index f6fc5c1a4078..0fd5b4c88358 100644 --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c @@ -3318,21 +3318,6 @@ int sctp_process_asconf_ack(struct sctp_association *asoc, sctp_chunk_free(asconf); asoc->addip_last_asconf = NULL; - /* Send the next asconf chunk from the addip chunk queue. */ - if (!list_empty(&asoc->addip_chunk_list)) { - struct list_head *entry = asoc->addip_chunk_list.next; - asconf = list_entry(entry, struct sctp_chunk, list); - - list_del_init(entry); - - /* Hold the chunk until an ASCONF_ACK is received. */ - sctp_chunk_hold(asconf); - if (sctp_primitive_ASCONF(asoc, asconf)) - sctp_chunk_free(asconf); - else - asoc->addip_last_asconf = asconf; - } - return retval; } diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c index 4c5bed9af4e3..d5ae450b6f02 100644 --- a/net/sctp/sm_sideeffect.c +++ b/net/sctp/sm_sideeffect.c @@ -962,6 +962,29 @@ static int sctp_cmd_send_msg(struct sctp_association *asoc, } +/* Sent the next ASCONF packet currently stored in the association. + * This happens after the ASCONF_ACK was succeffully processed. + */ +static void sctp_cmd_send_asconf(struct sctp_association *asoc) +{ + /* Send the next asconf chunk from the addip chunk + * queue. + */ + if (!list_empty(&asoc->addip_chunk_list)) { + struct list_head *entry = asoc->addip_chunk_list.next; + struct sctp_chunk *asconf = list_entry(entry, + struct sctp_chunk, list); + list_del_init(entry); + + /* Hold the chunk until an ASCONF_ACK is received. */ + sctp_chunk_hold(asconf); + if (sctp_primitive_ASCONF(asoc, asconf)) + sctp_chunk_free(asconf); + else + asoc->addip_last_asconf = asconf; + } +} + /* These three macros allow us to pull the debugging code out of the * main flow of sctp_do_sm() to keep attention focused on the real @@ -1617,6 +1640,9 @@ static int sctp_cmd_interpreter(sctp_event_t event_type, } error = sctp_cmd_send_msg(asoc, cmd->obj.msg); break; + case SCTP_CMD_SEND_NEXT_ASCONF: + sctp_cmd_send_asconf(asoc); + break; default: printk(KERN_WARNING "Impossible command: %u, %p\n", cmd->verb, cmd->obj.ptr); diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index abf601a1b847..24b2cd555637 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -3676,8 +3676,14 @@ sctp_disposition_t sctp_sf_do_asconf_ack(const struct sctp_endpoint *ep, SCTP_TO(SCTP_EVENT_TIMEOUT_T4_RTO)); if (!sctp_process_asconf_ack((struct sctp_association *)asoc, - asconf_ack)) + asconf_ack)) { + /* Successfully processed ASCONF_ACK. We can + * release the next asconf if we have one. + */ + sctp_add_cmd_sf(commands, SCTP_CMD_SEND_NEXT_ASCONF, + SCTP_NULL()); return SCTP_DISPOSITION_CONSUME; + } abort = sctp_make_abort(asoc, asconf_ack, sizeof(sctp_errhdr_t));