This is a note to let you know that I've just added the patch titled sctp: sctp should release assoc when sctp_make_abort_user return NULL in sctp_close to the 3.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: sctp-sctp-should-release-assoc-when-sctp_make_abort_user-return-null-in-sctp_close.patch and it can be found in the queue-3.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Tue Jan 26 22:24:47 PST 2016 From: Xin Long <lucien.xin@xxxxxxxxx> Date: Tue, 29 Dec 2015 17:49:25 +0800 Subject: sctp: sctp should release assoc when sctp_make_abort_user return NULL in sctp_close Status: RO Content-Length: 2604 Lines: 68 From: Xin Long <lucien.xin@xxxxxxxxx> [ Upstream commit 068d8bd338e855286aea54e70d1c101569284b21 ] In sctp_close, sctp_make_abort_user may return NULL because of memory allocation failure. If this happens, it will bypass any state change and never free the assoc. The assoc has no chance to be freed and it will be kept in memory with the state it had even after the socket is closed by sctp_close(). So if sctp_make_abort_user fails to allocate memory, we should abort the asoc via sctp_primitive_ABORT as well. Just like the annotation in sctp_sf_cookie_wait_prm_abort and sctp_sf_do_9_1_prm_abort said, "Even if we can't send the ABORT due to low memory delete the TCB. This is a departure from our typical NOMEM handling". But then the chunk is NULL (low memory) and the SCTP_CMD_REPLY cmd would dereference the chunk pointer, and system crash. So we should add SCTP_CMD_REPLY cmd only when the chunk is not NULL, just like other places where it adds SCTP_CMD_REPLY cmd. Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/sctp/sm_statefuns.c | 6 ++++-- net/sctp/socket.c | 3 +-- 2 files changed, 5 insertions(+), 4 deletions(-) --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -4835,7 +4835,8 @@ sctp_disposition_t sctp_sf_do_9_1_prm_ab retval = SCTP_DISPOSITION_CONSUME; - sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); + if (abort) + sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); /* Even if we can't send the ABORT due to low memory delete the * TCB. This is a departure from our typical NOMEM handling. @@ -4972,7 +4973,8 @@ sctp_disposition_t sctp_sf_cookie_wait_p SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT)); retval = SCTP_DISPOSITION_CONSUME; - sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); + if (abort) + sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE, SCTP_STATE(SCTP_STATE_CLOSED)); --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -1533,8 +1533,7 @@ SCTP_STATIC void sctp_close(struct sock struct sctp_chunk *chunk; chunk = sctp_make_abort_user(asoc, NULL, 0); - if (chunk) - sctp_primitive_ABORT(net, asoc, chunk); + sctp_primitive_ABORT(net, asoc, chunk); } else sctp_primitive_SHUTDOWN(net, asoc, NULL); } Patches currently in stable-queue which might be from lucien.xin@xxxxxxxxx are queue-3.10/sctp-sctp-should-release-assoc-when-sctp_make_abort_user-return-null-in-sctp_close.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html