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2014-10-14isdn/capi: prevent NULL pointer dereference on invalid CAPI commandTilman Schmidt
An invalid CAPI 2.0 command/subcommand combination may retrieve a NULL pointer from the cpars[] array which will later be dereferenced by the parser routines. Fix by adding NULL pointer checks in strategic places. Signed-off-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14isdn/capi: refactor command/subcommand table accessesTilman Schmidt
Encapsulate accesses to the CAPI 2.0 command/subcommand name and parameter tables in a single place in preparation for redesign. Signed-off-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14isdn/capi: prevent index overrun from command_2_index()Tilman Schmidt
The result of the function command_2_index() is used to index two arrays mnames[] and cpars[] with max. index 0x4e but in its current form that function can produce results up to 3*(0x9+0x9)+0x7f = 0xb5. Fix by clamping all result values potentially overrunning the arrays to zero which is already handled as an invalid value. Re-spotted with Coverity. Signed-off-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14isdn/capi: correct capi20_manufacturer argument type mismatchTilman Schmidt
Function capi20_manufacturer() is declared with unsigned int cmd argument but called with unsigned long. Fix by correcting the function prototype since the actual argument is part of the user visible API. Spotted with Coverity. Signed-off-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14isdn/gigaset: fix non-heap pointer deallocationTilman Schmidt
at_state structures may be allocated individually or as part of a cardstate or bc_state structure. The disconnect() function handled both cases, creating a risk that it might try to deallocate an at_state structure that had not been allocated individually. Fix by splitting disconnect() into two variants handling cases with and without an associated B channel separately, and adding an explicit check. Spotted with Coverity. Signed-off-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14isdn/gigaset: fix NULL pointer dereferenceTilman Schmidt
In do_action, a NULL pointer might be passed to function start_dial which will dereference it. Fix by adding a check for NULL before the call. Spotted with Coverity. Signed-off-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14isdn/gigaset: limit raw CAPI message dump lengthTilman Schmidt
In dump_rawmsg, the length field from a received data package was used unscrutinized, allowing an attacker to control the size of the allocated buffer and the number of times the output loop iterates. Fix by limiting to a reasonable value. Spotted with Coverity. Signed-off-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14isdn/gigaset: make sure controller name is null terminatedTilman Schmidt
In gigaset_isdn_regdev, the name field may not have a null terminator if the source string's length is equal to the buffer size. Fix by zero filling the structure and excluding the last byte of the name field from the copy. Spotted with Coverity. Signed-off-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14isdn/gigaset: missing break in do_facility_reqTilman Schmidt
If we take the unsupported supplementary service notification mask path, we end up falling through and overwriting the error code. Insert a break statement to skip the remainder of the switch case and proceed to sending the reply message. Spotted with Coverity. Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: Tilman Schmidt <tilman@imap.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14Merge branch 'fec-ptp'David S. Miller
Luwei Zhou says: ==================== Enable FEC pps feather Change from v2 to v3: -Using the default channel 0 to be PPS channel not PTP_PIN_SET/GETFUNC interface. -Using the linux definition of NSEC_PER_SEC. Change from v1 to v2: - Fix the potential 32-bit multiplication overflow issue. - Optimize the hareware adjustment code to improve efficiency as Richard suggested - Use ptp PTP_PIN_SET/GETFUNC interface to set PPS channel not device tree and add PTP_PF_PPS enumeration - Modify comments style ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14net: fec: ptp: Enable PPS output based on ptp clockLuwei Zhou
FEC ptp timer has 4 channel compare/trigger function. It can be used to enable pps output. The pulse would be ouput high exactly on N second. The pulse ouput high on compare event mode is used to produce pulse per second. The pulse width would be one cycle based on ptp timer clock source.Since 31-bit ptp hardware timer is used, the timer will wrap more than 2 seconds. We need to reload the compare compare event about every 1 second. Signed-off-by: Luwei Zhou <b45643@freescale.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14net: fec: ptp: Use hardware algorithm to adjust PTP counter.Luwei Zhou
The FEC IP supports hardware adjustment for ptp timer. Refer to the description of ENET_ATCOR and ENET_ATINC registers in the spec about the hardware adjustment. This patch uses hardware support to adjust the ptp offset and frequency on the slave side. Signed-off-by: Luwei Zhou <b45643@freescale.com> Signed-off-by: Frank Li <Frank.Li@freescale.com> Signed-off-by: Fugang Duan <b38611@freescale.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14net: fec: ptp: Use the 31-bit ptp timer.Luwei Zhou
When ptp switches from software adjustment to hardware ajustment, linux ptp can't converge. It is caused by the IP limit. Hardware adjustment logcial have issue when ptp counter runs over 0x80000000(31 bit counter). The internal IP reference manual already remove 32bit free-running count support. This patch replace the 32-bit PTP timer with 31-bit. Signed-off-by: Luwei Zhou <b45643@freescale.com> Signed-off-by: Frank Li <Frank.Li@freescale.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14ipv6: remove aca_lock spinlock from struct ifacaddr6Li RongQing
no user uses this lock. Signed-off-by: Li RongQing <roy.qing.li@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14x86: bpf_jit: fix two bugs in eBPF JIT compilerAlexei Starovoitov
1. JIT compiler using multi-pass approach to converge to final image size, since x86 instructions are variable length. It starts with large gaps between instructions (so some jumps may use imm32 instead of imm8) and iterates until total program size is the same as in previous pass. This algorithm works only if program size is strictly decreasing. Programs that use LD_ABS insn need additional code in prologue, but it was not emitted during 1st pass, so there was a chance that 2nd pass would adjust imm32->imm8 jump offsets to the same number of bytes as increase in prologue, which may cause algorithm to erroneously decide that size converged. Fix it by always emitting largest prologue in the first pass which is detected by oldproglen==0 check. Also change error check condition 'proglen != oldproglen' to fail gracefully. 2. while staring at the code realized that 64-byte buffer may not be enough when 1st insn is large, so increase it to 128 to avoid buffer overflow (theoretical maximum size of prologue+div is 109) and add runtime check. Fixes: 622582786c9e ("net: filter: x86: internal BPF JIT") Reported-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Tested-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14tcp: fix ooo_okay setting vs Small QueuesEric Dumazet
TCP Small Queues (tcp_tsq_handler()) can hold one reference on sk->sk_wmem_alloc, preventing skb->ooo_okay being set. We should relax test done to set skb->ooo_okay to take care of this extra reference. Minimal truesize of skb containing one byte of payload is SKB_TRUESIZE(1) Without this fix, we have more chance locking flows into the wrong transmit queue. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14skbuff: fix ftrace handling in skb_unshareAlexander Aring
If the skb is not dropped afterwards we should run consume_skb instead kfree_skb. Inside of function skb_unshare we do always a kfree_skb, doesn't depend if skb_copy failed or was successful. This patch switch this behaviour like skb_share_check, if allocation of sk_buff failed we use kfree_skb otherwise consume_skb. Signed-off-by: Alexander Aring <alex.aring@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14fm10k: Add skb->xmit_more supportAlexander Duyck
This change adds support for skb->xmit_more based on the changes that were made to igb to support the feature. The main changes are moving up the check for maybe_stop_tx so that we can check netif_xmit_stopped to determine if we must write the tail because we can add no further buffers. Acked-by: Matthew Vick <matthew.vick@intel.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14ceph: remove redundant code for max file size verificationChao Yu
Both ceph_update_writeable_page and ceph_setattr will verify file size with max size ceph supported. There are two caller for ceph_update_writeable_page, ceph_write_begin and ceph_page_mkwrite. For ceph_write_begin, we have already verified the size in generic_write_checks of ceph_write_iter; for ceph_page_mkwrite, we have no chance to change file size when mmap. Likewise we have already verified the size in inode_change_ok when we call ceph_setattr. So let's remove the redundant code for max file size verification. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Reviewed-by: Yan, Zheng <zyan@redhat.com>
2014-10-14ceph: remove redundant io_iter_advance()Yan, Zheng
ceph_sync_read and generic_file_read_iter() have already advanced the IO iterator. Signed-off-by: Yan, Zheng <zyan@redhat.com>
2014-10-14ceph: move ceph_find_inode() outside the s_mutexYan, Zheng
ceph_find_inode() may wait on freeing inode, using it inside the s_mutex may cause deadlock. (the freeing inode is waiting for OSD read reply, but dispatch thread is blocked by the s_mutex) Signed-off-by: Yan, Zheng <zyan@redhat.com> Reviewed-by: Sage Weil <sage@redhat.com>
2014-10-14ceph: request xattrs if xattr_version is zeroYan, Zheng
Following sequence of events can happen. - Client releases an inode, queues cap release message. - A 'lookup' reply brings the same inode back, but the reply doesn't contain xattrs because MDS didn't receive the cap release message and thought client already has up-to-data xattrs. The fix is force sending a getattr request to MDS if xattrs_version is 0. The getattr mask is set to CEPH_STAT_CAP_XATTR, so MDS knows client does not have xattr. Signed-off-by: Yan, Zheng <zyan@redhat.com>
2014-10-14rbd: set the remaining discard properties to enable supportJosh Durgin
max_discard_sectors must be set for the queue to support discard. Operations implementing discard for rbd zero data, so report that. Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
2014-10-14rbd: use helpers to handle discard for layered images correctlyJosh Durgin
Only allocate two osd ops for discard requests, since the preallocation hint is only added for regular writes. Use rbd_img_obj_request_fill() to recreate the original write or discard osd operations, isolating that logic to one place, and change the assert in rbd_osd_req_create_copyup() to accept discard requests as well. Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
2014-10-14rbd: extract a method for adding object operationsJosh Durgin
rbd_img_request_fill() creates a ceph_osd_request and has logic for adding the appropriate osd ops to it based on the request type and image properties. For layered images, the original rbd_obj_request is resent with a copyup operation in front, using a new ceph_osd_request. The logic for adding the original operations should be the same as when first sending them, so move it to a helper function. op_type only needs to be checked once, so create a helper for that as well and call it outside the loop in rbd_img_request_fill(). Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
2014-10-14rbd: make discard trigger copy-on-writeJosh Durgin
Discard requests are a form of write, so they should go through the same process as plain write requests and trigger copy-on-write for layered images. Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
2014-10-14rbd: tolerate -ENOENT for discard operationsJosh Durgin
Discard may try to delete an object from a non-layered image that does not exist. If this occurs, the image already has no data in that range, so change the result to success. Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
2014-10-14rbd: fix snapshot context reference count for discardsJosh Durgin
Discards take a reference to the snapshot context of an image when they are created. This reference needs to be cleaned up when the request is done just as it is for regular writes. Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
2014-10-14rbd: read image size for discard check safelyJosh Durgin
In rbd_img_request_fill() the image size is only checked to determine whether we can truncate an object instead of zeroing it for discard requests. Take rbd_dev->header_rwsem while reading the image size, and move this read into the discard check, so that non-discard ops don't need to take the semaphore in this function. Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
2014-10-14rbd: initial discard bits from Guangliang ZhaoGuangliang Zhao
This patch add the discard support for rbd driver. There are three types operation in the driver: 1. The objects would be removed if they completely contained within the discard range. 2. The objects would be truncated if they partly contained within the discard range, and align with their boundary. 3. Others would be zeroed. A discard request from blkdev_issue_discard() is defined which REQ_WRITE and REQ_DISCARD both marked and no data, so we must check the REQ_DISCARD first when getting the request type. This resolve: http://tracker.ceph.com/issues/190 [ Ilya Dryomov: This is incomplete and somewhat buggy, see follow up commits by Josh Durgin for refinements and fixes which weren't folded in to preserve authorship. ] Signed-off-by: Guangliang Zhao <lucienchao@gmail.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org>
2014-10-14rbd: extend the operation typeGuangliang Zhao
It could only handle the read and write operations now, extend it for the coming discard support. Signed-off-by: Guangliang Zhao <lucienchao@gmail.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org>
2014-10-14rbd: skip the copyup when an entire object writingGuangliang Zhao
It need to copyup the parent's content when layered writing, but an entire object write would overwrite it, so skip it. Signed-off-by: Guangliang Zhao <lucienchao@gmail.com> Reviewed-by: Josh Durgin <josh.durgin@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org>
2014-10-14rbd: add img_obj_request_simple() helperIlya Dryomov
To clarify the conditions and make it easier to add new ones. Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
2014-10-14rbd: access snapshot context and mapping size safelyJosh Durgin
These fields may both change while the image is mapped if a snapshot is created or deleted or the image is resized. They are guarded by rbd_dev->header_rwsem, so hold that while reading them, and store a local copy to refer to outside of the critical section. The local copy will stay consistent since the snapshot context is reference counted, and the mapping size is just a u64. This prevents torn loads from giving us inconsistent values. Move reading header.snapc into the caller of rbd_img_request_create() so that we only need to take the semaphore once. The read-only caller, rbd_parent_request_create() can just pass NULL for snapc, since the snapshot context is only relevant for writes. Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
2014-10-14rbd: do not return -ERANGE on auth failuresIlya Dryomov
Trying to map an image out of a pool for which we don't have an 'x' permission bit fails with -ERANGE from ceph_extract_encoded_string() due to an unsigned vs signed bug. Fix it and get rid of the -EINVAL sink, thus propagating rbd::get_id cls method errors. (I've seen a bunch of unexplained -ERANGE reports, I bet this is it). Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org>
2014-10-14libceph: don't try checking queue_work() return valueIlya Dryomov
queue_work() doesn't "fail to queue", it returns false if work was already on a queue, which can't happen here since we allocate event_work right before we queue it. So don't bother at all. Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org>
2014-10-14ceph: make sure request isn't in any waiting list when kicking request.Yan, Zheng
we may corrupt waiting list if a request in the waiting list is kicked. Signed-off-by: Yan, Zheng <zyan@redhat.com> Reviewed-by: Sage Weil <sage@redhat.com>
2014-10-14ceph: protect kick_requests() with mdsc->mutexYan, Zheng
Signed-off-by: Yan, Zheng <zyan@redhat.com> Reviewed-by: Sage Weil <sage@redhat.com>
2014-10-14libceph: Convert pr_warning to pr_warnJoe Perches
Use the more common pr_warn. Other miscellanea: o Coalesce formats o Realign arguments Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
2014-10-14ceph: trim unused inodes before reconnecting to recovering MDSYan, Zheng
So the recovering MDS does not need to fetch these ununsed inodes during cache rejoin. This may reduce MDS recovery time. Signed-off-by: Yan, Zheng <zyan@redhat.com>
2014-10-14libceph: fix a use after free issue in osdmap_set_max_osdLi RongQing
If the state variable is krealloced successfully, map->osd_state will be freed, once following two reallocation failed, and exit the function without resetting map->osd_state, map->osd_state become a wild pointer. fix it by resetting them after krealloc successfully. Signed-off-by: Li RongQing <roy.qing.li@gmail.com> Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
2014-10-14libceph: select CRYPTO_CBC in addition to CRYPTO_AESIlya Dryomov
We want "cbc(aes)" algorithm, so select CRYPTO_CBC too, not just CRYPTO_AES. Otherwise on !CRYPTO_CBC kernels we fail rbd map/mount with libceph: error -2 building auth method x request Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com>
2014-10-14libceph: resend lingering requests with a new tidIlya Dryomov
Both not yet registered (r_linger && list_empty(&r_linger_item)) and registered linger requests should use the new tid on resend to avoid the dup op detection logic on the OSDs, yet we were doing this only for "registered" case. Factor out and simplify the "registered" logic and use the new helper for "not registered" case as well. Fixes: http://tracker.ceph.com/issues/8806 Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org>
2014-10-14libceph: abstract out ceph_osd_request enqueue logicIlya Dryomov
Introduce __enqueue_request() and switch to it. Signed-off-by: Ilya Dryomov <ilya.dryomov@inktank.com> Reviewed-by: Alex Elder <elder@linaro.org>
2014-10-14net: fec: Fix sparse warnings with different lock contexts for basic blockNimrod Andy
reproduce: make ARCH=arm C=1 2>fec.txt drivers/net/ethernet/freescale/fec_main.o cat fec.txt sparse warnings: drivers/net/ethernet/freescale/fec_main.c:2916:12: warning: context imbalance in 'fec_set_features' - different lock contexts for basic block Christopher Li suggest to change as below: if (need_lock) { lock(); do_something_real(); unlock(); } else { do_something_real(); } Reported-by: Fabio Estevam <festevam@gmail.com> Suggested-by: Christopher Li <sparse@chrisli.org> Signed-off-by: Fugang Duan <B38611@freescale.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14MAINTAINERS: Update contact information for Vince BridgersVince Bridgers
Signed-off-by: Vince Bridgers <vbridger@opensource.altera.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14Merge branch 'sctp'David S. Miller
Daniel Borkmann says: ==================== Here are some SCTP fixes. [ Note, immediate workaround would be to disable ASCONF (it is sysctl disabled by default). It is actually only used together with chunk authentication. ] ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14net: sctp: fix remote memory pressure from excessive queueingDaniel Borkmann
This scenario is not limited to ASCONF, just taken as one example triggering the issue. When receiving ASCONF probes in the form of ... -------------- INIT[ASCONF; ASCONF_ACK] -------------> <----------- INIT-ACK[ASCONF; ASCONF_ACK] ------------ -------------------- COOKIE-ECHO --------------------> <-------------------- COOKIE-ACK --------------------- ---- ASCONF_a; [ASCONF_b; ...; ASCONF_n;] JUNK ------> [...] ---- ASCONF_m; [ASCONF_o; ...; ASCONF_z;] JUNK ------> ... where ASCONF_a, ASCONF_b, ..., ASCONF_z are good-formed ASCONFs and have increasing serial numbers, we process such ASCONF chunk(s) marked with !end_of_packet and !singleton, since we have not yet reached the SCTP packet end. SCTP does only do verification on a chunk by chunk basis, as an SCTP packet is nothing more than just a container of a stream of chunks which it eats up one by one. We could run into the case that we receive a packet with a malformed tail, above marked as trailing JUNK. All previous chunks are here goodformed, so the stack will eat up all previous chunks up to this point. In case JUNK does not fit into a chunk header and there are no more other chunks in the input queue, or in case JUNK contains a garbage chunk header, but the encoded chunk length would exceed the skb tail, or we came here from an entirely different scenario and the chunk has pdiscard=1 mark (without having had a flush point), it will happen, that we will excessively queue up the association's output queue (a correct final chunk may then turn it into a response flood when flushing the queue ;)): I ran a simple script with incremental ASCONF serial numbers and could see the server side consuming excessive amount of RAM [before/after: up to 2GB and more]. The issue at heart is that the chunk train basically ends with !end_of_packet and !singleton markers and since commit 2e3216cd54b1 ("sctp: Follow security requirement of responding with 1 packet") therefore preventing an output queue flush point in sctp_do_sm() -> sctp_cmd_interpreter() on the input chunk (chunk = event_arg) even though local_cork is set, but its precedence has changed since then. In the normal case, the last chunk with end_of_packet=1 would trigger the queue flush to accommodate possible outgoing bundling. In the input queue, sctp_inq_pop() seems to do the right thing in terms of discarding invalid chunks. So, above JUNK will not enter the state machine and instead be released and exit the sctp_assoc_bh_rcv() chunk processing loop. It's simply the flush point being missing at loop exit. Adding a try-flush approach on the output queue might not work as the underlying infrastructure might be long gone at this point due to the side-effect interpreter run. One possibility, albeit a bit of a kludge, would be to defer invalid chunk freeing into the state machine in order to possibly trigger packet discards and thus indirectly a queue flush on error. It would surely be better to discard chunks as in the current, perhaps better controlled environment, but going back and forth, it's simply architecturally not possible. I tried various trailing JUNK attack cases and it seems to look good now. Joint work with Vlad Yasevich. Fixes: 2e3216cd54b1 ("sctp: Follow security requirement of responding with 1 packet") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14net: sctp: fix panic on duplicate ASCONF chunksDaniel Borkmann
When receiving a e.g. semi-good formed connection scan in the form of ... -------------- INIT[ASCONF; ASCONF_ACK] -------------> <----------- INIT-ACK[ASCONF; ASCONF_ACK] ------------ -------------------- COOKIE-ECHO --------------------> <-------------------- COOKIE-ACK --------------------- ---------------- ASCONF_a; ASCONF_b -----------------> ... where ASCONF_a equals ASCONF_b chunk (at least both serials need to be equal), we panic an SCTP server! The problem is that good-formed ASCONF chunks that we reply with ASCONF_ACK chunks are cached per serial. Thus, when we receive a same ASCONF chunk twice (e.g. through a lost ASCONF_ACK), we do not need to process them again on the server side (that was the idea, also proposed in the RFC). Instead, we know it was cached and we just resend the cached chunk instead. So far, so good. Where things get nasty is in SCTP's side effect interpreter, that is, sctp_cmd_interpreter(): While incoming ASCONF_a (chunk = event_arg) is being marked !end_of_packet and !singleton, and we have an association context, we do not flush the outqueue the first time after processing the ASCONF_ACK singleton chunk via SCTP_CMD_REPLY. Instead, we keep it queued up, although we set local_cork to 1. Commit 2e3216cd54b1 changed the precedence, so that as long as we get bundled, incoming chunks we try possible bundling on outgoing queue as well. Before this commit, we would just flush the output queue. Now, while ASCONF_a's ASCONF_ACK sits in the corked outq, we continue to process the same ASCONF_b chunk from the packet. As we have cached the previous ASCONF_ACK, we find it, grab it and do another SCTP_CMD_REPLY command on it. So, effectively, we rip the chunk->list pointers and requeue the same ASCONF_ACK chunk another time. Since we process ASCONF_b, it's correctly marked with end_of_packet and we enforce an uncork, and thus flush, thus crashing the kernel. Fix it by testing if the ASCONF_ACK is currently pending and if that is the case, do not requeue it. When flushing the output queue we may relink the chunk for preparing an outgoing packet, but eventually unlink it when it's copied into the skb right before transmission. Joint work with Vlad Yasevich. Fixes: 2e3216cd54b1 ("sctp: Follow security requirement of responding with 1 packet") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-14net: sctp: fix skb_over_panic when receiving malformed ASCONF chunksDaniel Borkmann
Commit 6f4c618ddb0 ("SCTP : Add paramters validity check for ASCONF chunk") added basic verification of ASCONF chunks, however, it is still possible to remotely crash a server by sending a special crafted ASCONF chunk, even up to pre 2.6.12 kernels: skb_over_panic: text:ffffffffa01ea1c3 len:31056 put:30768 head:ffff88011bd81800 data:ffff88011bd81800 tail:0x7950 end:0x440 dev:<NULL> ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:129! [...] Call Trace: <IRQ> [<ffffffff8144fb1c>] skb_put+0x5c/0x70 [<ffffffffa01ea1c3>] sctp_addto_chunk+0x63/0xd0 [sctp] [<ffffffffa01eadaf>] sctp_process_asconf+0x1af/0x540 [sctp] [<ffffffff8152d025>] ? _read_unlock_bh+0x15/0x20 [<ffffffffa01e0038>] sctp_sf_do_asconf+0x168/0x240 [sctp] [<ffffffffa01e3751>] sctp_do_sm+0x71/0x1210 [sctp] [<ffffffff8147645d>] ? fib_rules_lookup+0xad/0xf0 [<ffffffffa01e6b22>] ? sctp_cmp_addr_exact+0x32/0x40 [sctp] [<ffffffffa01e8393>] sctp_assoc_bh_rcv+0xd3/0x180 [sctp] [<ffffffffa01ee986>] sctp_inq_push+0x56/0x80 [sctp] [<ffffffffa01fcc42>] sctp_rcv+0x982/0xa10 [sctp] [<ffffffffa01d5123>] ? ipt_local_in_hook+0x23/0x28 [iptable_filter] [<ffffffff8148bdc9>] ? nf_iterate+0x69/0xb0 [<ffffffff81496d10>] ? ip_local_deliver_finish+0x0/0x2d0 [<ffffffff8148bf86>] ? nf_hook_slow+0x76/0x120 [<ffffffff81496d10>] ? ip_local_deliver_finish+0x0/0x2d0 [<ffffffff81496ded>] ip_local_deliver_finish+0xdd/0x2d0 [<ffffffff81497078>] ip_local_deliver+0x98/0xa0 [<ffffffff8149653d>] ip_rcv_finish+0x12d/0x440 [<ffffffff81496ac5>] ip_rcv+0x275/0x350 [<ffffffff8145c88b>] __netif_receive_skb+0x4ab/0x750 [<ffffffff81460588>] netif_receive_skb+0x58/0x60 This can be triggered e.g., through a simple scripted nmap connection scan injecting the chunk after the handshake, for example, ... -------------- INIT[ASCONF; ASCONF_ACK] -------------> <----------- INIT-ACK[ASCONF; ASCONF_ACK] ------------ -------------------- COOKIE-ECHO --------------------> <-------------------- COOKIE-ACK --------------------- ------------------ ASCONF; UNKNOWN ------------------> ... where ASCONF chunk of length 280 contains 2 parameters ... 1) Add IP address parameter (param length: 16) 2) Add/del IP address parameter (param length: 255) ... followed by an UNKNOWN chunk of e.g. 4 bytes. Here, the Address Parameter in the ASCONF chunk is even missing, too. This is just an example and similarly-crafted ASCONF chunks could be used just as well. The ASCONF chunk passes through sctp_verify_asconf() as all parameters passed sanity checks, and after walking, we ended up successfully at the chunk end boundary, and thus may invoke sctp_process_asconf(). Parameter walking is done with WORD_ROUND() to take padding into account. In sctp_process_asconf()'s TLV processing, we may fail in sctp_process_asconf_param() e.g., due to removal of the IP address that is also the source address of the packet containing the ASCONF chunk, and thus we need to add all TLVs after the failure to our ASCONF response to remote via helper function sctp_add_asconf_response(), which basically invokes a sctp_addto_chunk() adding the error parameters to the given skb. When walking to the next parameter this time, we proceed with ... length = ntohs(asconf_param->param_hdr.length); asconf_param = (void *)asconf_param + length; ... instead of the WORD_ROUND()'ed length, thus resulting here in an off-by-one that leads to reading the follow-up garbage parameter length of 12336, and thus throwing an skb_over_panic for the reply when trying to sctp_addto_chunk() next time, which implicitly calls the skb_put() with that length. Fix it by using sctp_walk_params() [ which is also used in INIT parameter processing ] macro in the verification *and* in ASCONF processing: it will make sure we don't spill over, that we walk parameters WORD_ROUND()'ed. Moreover, we're being more defensive and guard against unknown parameter types and missized addresses. Joint work with Vlad Yasevich. Fixes: b896b82be4ae ("[SCTP] ADDIP: Support for processing incoming ASCONF_ACK chunks.") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>