kernel.git/net/sctp/socket.c, branch linux-3.12.y

sctp: listen on the sock only when it's state is listening or closed

2017-05-09T06:19:48Z

[ Upstream commit 34b2789f1d9bf8dcca9b5cb553d076ca2cd898ee ] Now sctp doesn't check sock's state before listening on it. It could even cause changing a sock with any state to become a listening sock when doing sctp_listen. This patch is to fix it by checking sock's state in sctp_listen, so that it will listen on the sock with right state. Reported-by: Andrey Konovalov Tested-by: Andrey Konovalov Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: deny peeloff operation on asocs with threads sleeping on it

2017-03-11T14:37:02Z

commit dfcb9f4f99f1e9a49e43398a7bfbf56927544af1 upstream. commit 2dcab5984841 ("sctp: avoid BUG_ON on sctp_wait_for_sndbuf") attempted to avoid a BUG_ON call when the association being used for a sendmsg() is blocked waiting for more sndbuf and another thread did a peeloff operation on such asoc, moving it to another socket. As Ben Hutchings noticed, then in such case it would return without locking back the socket and would cause two unlocks in a row. Further analysis also revealed that it could allow a double free if the application managed to peeloff the asoc that is created during the sendmsg call, because then sctp_sendmsg() would try to free the asoc that was created only for that call. This patch takes another approach. It will deny the peeloff operation if there is a thread sleeping on the asoc, so this situation doesn't exist anymore. This avoids the issues described above and also honors the syscalls that are already being handled (it can be multiple sendmsg calls). Joint work with Xin Long. Fixes: 2dcab5984841 ("sctp: avoid BUG_ON on sctp_wait_for_sndbuf") Cc: Alexander Popov Cc: Ben Hutchings Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby

sctp: avoid BUG_ON on sctp_wait_for_sndbuf

2017-03-01T08:59:48Z

[ Upstream commit 2dcab598484185dea7ec22219c76dcdd59e3cb90 ] Alexander Popov reported that an application may trigger a BUG_ON in sctp_wait_for_sndbuf if the socket tx buffer is full, a thread is waiting on it to queue more data and meanwhile another thread peels off the association being used by the first thread. This patch replaces the BUG_ON call with a proper error handling. It will return -EPIPE to the original sendmsg call, similarly to what would have been done if the association wasn't found in the first place. Acked-by: Alexander Popov Signed-off-by: Marcelo Ricardo Leitner Reviewed-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby

sctp: assign assoc_id earlier in __sctp_connect

2016-11-28T21:22:38Z

[ Upstream commit 7233bc84a3aeda835d334499dc00448373caf5c0 ] sctp_wait_for_connect() currently already holds the asoc to keep it alive during the sleep, in case another thread release it. But Andrey Konovalov and Dmitry Vyukov reported an use-after-free in such situation. Problem is that __sctp_connect() doesn't get a ref on the asoc and will do a read on the asoc after calling sctp_wait_for_connect(), but by then another thread may have closed it and the _put on sctp_wait_for_connect will actually release it, causing the use-after-free. Fix is, instead of doing the read after waiting for the connect, do it before so, and avoid this issue as the socket is still locked by then. There should be no issue on returning the asoc id in case of failure as the application shouldn't trust on that number in such situations anyway. This issue doesn't exist in sctp_sendmsg() path. Reported-by: Dmitry Vyukov Reported-by: Andrey Konovalov Tested-by: Andrey Konovalov Signed-off-by: Marcelo Ricardo Leitner Reviewed-by: Xin Long Acked-by: Neil Horman Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby

net: sctp, forbid negative length

2016-11-28T21:22:30Z

[ Upstream commit a4b8e71b05c27bae6bad3bdecddbc6b68a3ad8cf ] Most of getsockopt handlers in net/sctp/socket.c check len against sizeof some structure like: if (len < sizeof(int)) return -EINVAL; On the first look, the check seems to be correct. But since len is int and sizeof returns size_t, int gets promoted to unsigned size_t too. So the test returns false for negative lengths. Yes, (-1 < sizeof(long)) is false. Fix this in sctp by explicitly checking len < 0 before any getsockopt handler is called. Note that sctp_getsockopt_events already handled the negative case. Since we added the < 0 check elsewhere, this one can be removed. If not checked, this is the result: UBSAN: Undefined behaviour in ../mm/page_alloc.c:2722:19 shift exponent 52 is too large for 32-bit type 'int' CPU: 1 PID: 24535 Comm: syz-executor Not tainted 4.8.1-0-syzkaller #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.1-0-gb3ef39f-prebuilt.qemu-project.org 04/01/2014 0000000000000000 ffff88006d99f2a8 ffffffffb2f7bdea 0000000041b58ab3 ffffffffb4363c14 ffffffffb2f7bcde ffff88006d99f2d0 ffff88006d99f270 0000000000000000 0000000000000000 0000000000000034 ffffffffb5096422 Call Trace: [] ? __ubsan_handle_shift_out_of_bounds+0x29c/0x300 ... [] ? kmalloc_order+0x24/0x90 [] ? kmalloc_order_trace+0x24/0x220 [] ? __kmalloc+0x330/0x540 [] ? sctp_getsockopt_local_addrs+0x174/0xca0 [sctp] [] ? sctp_getsockopt+0x10d/0x1b0 [sctp] [] ? sock_common_getsockopt+0xb9/0x150 [] ? SyS_getsockopt+0x1a5/0x270 Signed-off-by: Jiri Slaby Cc: Vlad Yasevich Cc: Neil Horman Cc: "David S. Miller" Cc: linux-sctp@vger.kernel.org Cc: netdev@vger.kernel.org Acked-by: Neil Horman Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby

sctp: translate network order to host order when users get a hmacid

2016-03-02T15:29:08Z

[ Upstream commit 7a84bd46647ff181eb2659fdc99590e6f16e501d ] Commit ed5a377d87dc ("sctp: translate host order to network order when setting a hmacid") corrected the hmacid byte-order when setting a hmacid. but the same issue also exists on getting a hmacid. We fix it by changing hmacids to host order when users get them with getsockopt. Fixes: Commit ed5a377d87dc ("sctp: translate host order to network order when setting a hmacid") Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby

sctp: allow setting SCTP_SACK_IMMEDIATELY by the application

2016-03-02T15:29:05Z

[ Upstream commit 27f7ed2b11d42ab6d796e96533c2076ec220affc ] This patch extends commit b93d6471748d ("sctp: implement the sender side for SACK-IMMEDIATELY extension") as it didn't white list SCTP_SACK_IMMEDIATELY on sctp_msghdr_parse(), causing it to be understood as an invalid flag and returning -EINVAL to the application. Note that the actual handling of the flag is already there in sctp_datamsg_from_user(). https://tools.ietf.org/html/rfc7053#section-7 Fixes: b93d6471748d ("sctp: implement the sender side for SACK-IMMEDIATELY extension") Signed-off-by: Marcelo Ricardo Leitner Acked-by: Vlad Yasevich Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby

sctp: sctp should release assoc when sctp_make_abort_user return NULL in sctp_close

2016-01-28T08:41:33Z

[ 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 Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby

sctp: update the netstamp_needed counter when copying sockets

2016-01-05T16:57:50Z

[ Upstream commit 01ce63c90170283a9855d1db4fe81934dddce648 ] Dmitry Vyukov reported that SCTP was triggering a WARN on socket destroy related to disabling sock timestamp. When SCTP accepts an association or peel one off, it copies sock flags but forgot to call net_enable_timestamp() if a packet timestamping flag was copied, leading to extra calls to net_disable_timestamp() whenever such clones were closed. The fix is to call net_enable_timestamp() whenever we copy a sock with that flag on, like tcp does. Reported-by: Dmitry Vyukov Signed-off-by: Marcelo Ricardo Leitner Acked-by: Vlad Yasevich Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby

ipv6: sctp: implement sctp_v6_destroy_sock()

2016-01-05T15:11:15Z

[ Upstream commit 602dd62dfbda3e63a2d6a3cbde953ebe82bf5087 ] Dmitry Vyukov reported a memory leak using IPV6 SCTP sockets. We need to call inet6_destroy_sock() to properly release inet6 specific fields. Reported-by: Dmitry Vyukov Signed-off-by: Eric Dumazet Acked-by: Daniel Borkmann Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby