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2014-01-18net: add build-time checks for msg->msg_name sizeSteffen Hurrle
This is a follow-up patch to f3d3342602f8bc ("net: rework recvmsg handler msg_name and msg_namelen logic"). DECLARE_SOCKADDR validates that the structure we use for writing the name information to is not larger than the buffer which is reserved for msg->msg_name (which is 128 bytes). Also use DECLARE_SOCKADDR consistently in sendmsg code paths. Signed-off-by: Steffen Hurrle <steffen@hurrle.net> Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16tipc: standardize recvmsg routineYing Xue
Standardize the behaviour of waiting for events in TIPC recvmsg() so that all variables of socket or port structures are protected within socket lock, allowing the process of calling recvmsg() to be woken up at appropriate time. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16tipc: standardize sendmsg routine of connected socketYing Xue
Standardize the behaviour of waiting for events in TIPC send_packet() so that all variables of socket or port structures are protected within socket lock, allowing the process of calling sendmsg() to be woken up at appropriate time. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16tipc: standardize sendmsg routine of connectionless socketYing Xue
Comparing the behaviour of how to wait for events in TIPC sendmsg() with other stacks, the TIPC implementation might be perceived as different, and sometimes even incorrect. For instance, sk_sleep() and tport->congested variables associated with socket are exposed without socket lock protection while wait_event_interruptible_timeout() accesses them. So standardizing it with similar implementation in other stacks can help us correct these errors which the process of calling sendmsg() cannot be woken up event if an expected event arrive at socket or improperly woken up although the wake condition doesn't match. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16tipc: standardize accept routineYing Xue
Comparing the behaviour of how to wait for events in TIPC accept() with other stacks, the TIPC implementation might be perceived as different, and sometimes even incorrect. As sk_sleep() and sk->sk_receive_queue variables associated with socket are not protected by socket lock, the process of calling accept() may be woken up improperly or sometimes cannot be woken up at all. After standardizing it with inet_csk_wait_for_connect routine, we can get benefits including: avoiding 'thundering herd' phenomenon, adding a timeout mechanism for accept(), coping with a pending signal, and having sk_sleep() and sk->sk_receive_queue being always protected within socket lock scope and so on. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16tipc: standardize connect routineYing Xue
Comparing the behaviour of how to wait for events in TIPC connect() with other stacks, the TIPC implementation might be perceived as different, and sometimes even incorrect. For instance, as both sock->state and sk_sleep() are directly fed to wait_event_interruptible_timeout() as its arguments, and socket lock has to be released before we call wait_event_interruptible_timeout(), the two variables associated with socket are exposed out of socket lock protection, thereby probably getting stale values so that the process of calling connect() cannot be woken up exactly even if correct event arrives or it is woken up improperly even if the wake condition is not satisfied in practice. Therefore, standardizing its behaviour with sk_stream_wait_connect routine can avoid these risks. Additionally the implementation of connect routine is simplified as a whole, allowing it to return correct values in all different cases. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-14tipc: spelling fixesstephen hemminger
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2014-01-07tipc: make link start event synchronousJon Paul Maloy
When a link is created we delay the start event by launching it to be executed later in a tasklet. As we hold all the necessary locks at the moment of creation, and there is no risk of deadlock or contention, this delay serves no purpose in the current code. We remove this obsolete indirection step, and the associated function link_start(). At the same time, we rename the function tipc_link_stop() to the more appropriate tipc_link_purge_queues(). Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-07tipc: introduce new spinlock to protect struct link_reqYing Xue
Currently, only 'bearer_lock' is used to protect struct link_req in the function disc_timeout(). This is unsafe, since the member fields 'num_nodes' and 'timer_intv' might be accessed by below three different threads simultaneously, none of them grabbing bearer_lock in the critical region: link_activate() tipc_bearer_add_dest() tipc_disc_add_dest() req->num_nodes++; tipc_link_reset() tipc_bearer_remove_dest() tipc_disc_remove_dest() req->num_nodes-- disc_update() read req->num_nodes write req->timer_intv disc_timeout() read req->num_nodes read/write req->timer_intv Without lock protection, the only symptom of a race is that discovery messages occasionally may not be sent out. This is not fatal, since such messages are best-effort anyway. On the other hand, since discovery messages are not time critical, adding a protecting lock brings no serious overhead either. So we add a new, dedicated spinlock in order to guarantee absolute data consistency in link_req objects. This also helps reduce the overall role of the bearer_lock, which we want to remove completely in a later commit series. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-07tipc: remove 'has_redundant_link' flag from STATE link protocol messagesJon Paul Maloy
The flag 'has_redundant_link' is defined only in RESET and ACTIVATE protocol messages. Due to an ambiguity in the protocol specification it is currently also transferred in STATE messages. Its value is used to initialize a link state variable, 'permit_changeover', which is used to inhibit futile link failover attempts when it is known that the peer node has no working links at the moment, although the local node may still think it has one. The fact that 'has_redundant_link' incorrectly is read from STATE messages has the effect that 'permit_changeover' sometimes gets a wrong value, and permanently blocks any links from being re-established. Such failures can only occur in in dual-link systems, and are extremely rare. This bug seems to have always been present in the code. Furthermore, since commit b4b5610223f17790419b03eaa962b0e3ecf930d7 ("tipc: Ensure both nodes recognize loss of contact between them"), the 'permit_changeover' field serves no purpose any more. The task of enforcing 'lost contact' cycles at both peer endpoints is now taken by a new mechanism, using the flags WAIT_NODE_DOWN and WAIT_PEER_DOWN in struct tipc_node to abort unnecessary failover attempts. We therefore remove the 'has_redundant_link' flag from STATE messages, as well as the now redundant 'permit_changeover' variable. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-07tipc: rename functions related to link failover and improve commentsJon Paul Maloy
The functionality related to link addition and failover is unnecessarily hard to understand and maintain. We try to improve this by renaming some of the functions, at the same time adding or improving the explanatory comments around them. Names such as "tipc_rcv()" etc. also align better with what is used in other networking components. The changes in this commit are purely cosmetic, no functional changes are made. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-07tipc: correctly unlink packets from deferred packet queueErik Hugne
When we pull a received packet from a link's 'deferred packets' queue for processing, its 'next' pointer is not cleared, and still refers to the next packet in that queue, if any. This is incorrect, but caused no harm before commit 40ba3cdf542a469aaa9083fa041656e59b109b90 ("tipc: message reassembly using fragment chain") was introduced. After that commit, it may sometimes lead to the following oops: general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC Modules linked in: tipc CPU: 4 PID: 0 Comm: swapper/4 Tainted: G W 3.13.0-rc2+ #6 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 task: ffff880017af4880 ti: ffff880017aee000 task.ti: ffff880017aee000 RIP: 0010:[<ffffffff81710694>] [<ffffffff81710694>] skb_try_coalesce+0x44/0x3d0 RSP: 0018:ffff880016603a78 EFLAGS: 00010212 RAX: 6b6b6b6bd6d6d6d6 RBX: ffff880013106ac0 RCX: ffff880016603ad0 RDX: ffff880016603ad7 RSI: ffff88001223ed00 RDI: ffff880013106ac0 RBP: ffff880016603ab8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88001223ed00 R13: ffff880016603ad0 R14: 000000000000058c R15: ffff880012297650 FS: 0000000000000000(0000) GS:ffff880016600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b CR2: 000000000805b000 CR3: 0000000011f5d000 CR4: 00000000000006e0 Stack: ffff880016603a88 ffffffff810a38ed ffff880016603aa8 ffff88001223ed00 0000000000000001 ffff880012297648 ffff880016603b68 ffff880012297650 ffff880016603b08 ffffffffa0006c51 ffff880016603b08 00ffffffa00005fc Call Trace: <IRQ> [<ffffffff810a38ed>] ? trace_hardirqs_on+0xd/0x10 [<ffffffffa0006c51>] tipc_link_recv_fragment+0xd1/0x1b0 [tipc] [<ffffffffa0007214>] tipc_recv_msg+0x4e4/0x920 [tipc] [<ffffffffa00016f0>] ? tipc_l2_rcv_msg+0x40/0x250 [tipc] [<ffffffffa000177c>] tipc_l2_rcv_msg+0xcc/0x250 [tipc] [<ffffffffa00016f0>] ? tipc_l2_rcv_msg+0x40/0x250 [tipc] [<ffffffff8171e65b>] __netif_receive_skb_core+0x80b/0xd00 [<ffffffff8171df94>] ? __netif_receive_skb_core+0x144/0xd00 [<ffffffff8171eb76>] __netif_receive_skb+0x26/0x70 [<ffffffff8171ed6d>] netif_receive_skb+0x2d/0x200 [<ffffffff8171fe70>] napi_gro_receive+0xb0/0x130 [<ffffffff815647c2>] e1000_clean_rx_irq+0x2c2/0x530 [<ffffffff81565986>] e1000_clean+0x266/0x9c0 [<ffffffff81985f7b>] ? notifier_call_chain+0x2b/0x160 [<ffffffff8171f971>] net_rx_action+0x141/0x310 [<ffffffff81051c1b>] __do_softirq+0xeb/0x480 [<ffffffff819817bb>] ? _raw_spin_unlock+0x2b/0x40 [<ffffffff810b8c42>] ? handle_fasteoi_irq+0x72/0x100 [<ffffffff81052346>] irq_exit+0x96/0xc0 [<ffffffff8198cbc3>] do_IRQ+0x63/0xe0 [<ffffffff81981def>] common_interrupt+0x6f/0x6f <EOI> This happens when the last fragment of a message has passed through the the receiving link's 'deferred packets' queue, and at least one other packet was added to that queue while it was there. After the fragment chain with the complete message has been successfully delivered to the receiving socket, it is released. Since 'next' pointer of the last fragment in the released chain now is non-NULL, we get the crash shown above. We fix this by clearing the 'next' pointer of all received packets, including those being pulled from the 'deferred' queue, before they undergo any further processing. Fixes: 40ba3cdf542a4 ("tipc: message reassembly using fragment chain") Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Reported-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-06Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/qlogic/qlcnic/qlcnic_sriov_pf.c net/ipv6/ip6_tunnel.c net/ipv6/ip6_vti.c ipv6 tunnel statistic bug fixes conflicting with consolidation into generic sw per-cpu net stats. qlogic conflict between queue counting bug fix and the addition of multiple MAC address support. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-04tipc: remove unused codestephen hemminger
Remove dead code; tipc_bearer_find_interface tipc_node_redundant_links This may break out of tree version of TIPC if there still is one. But that maybe a good thing :-) Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-04tipc: make local function staticstephen hemminger
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-02tipc: make the code look more readablewangweidong
In commit 3b8401fe9d ("tipc: kill unnecessary goto's") didn't make the code look most readable, so fix it. This patch is cosmetic and does not change the operation of TIPC in any way. Suggested-by: David Laight <David.Laight@ACULAB.COM> Signed-off-by: Wang Weidong <wangweidong1@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-29tipc: fix deadlock during socket releaseYing Xue
A deadlock might occur if name table is withdrawn in socket release routine, and while packets are still being received from bearer. CPU0 CPU1 T0: recv_msg() release() T1: tipc_recv_msg() tipc_withdraw() T2: [grab node lock] [grab port lock] T3: tipc_link_wakeup_ports() tipc_nametbl_withdraw() T4: [grab port lock]* named_cluster_distribute() T5: wakeupdispatch() tipc_link_send() T6: [grab node lock]* The opposite order of holding port lock and node lock on above two different paths may result in a deadlock. If socket lock instead of port lock is used to protect port instance in tipc_withdraw(), the reverse order of holding port lock and node lock will be eliminated, as a result, the deadlock is killed as well. Reported-by: Lars Everbrand <lars.everbrand@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/intel/i40e/i40e_main.c drivers/net/macvtap.c Both minor merge hassles, simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-16tipc: change lock_sock order in connect()wangweidong
Instead of reaquiring the socket lock and taking the normal exit path when a connection times out, we bail out early with a return -ETIMEDOUT. Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Wang Weidong <wangweidong1@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-16tipc: Use <linux/uaccess.h> instead of <asm/uaccess.h>wangweidong
As warned by checkpatch.pl, use #include <linux/uaccess.h> instead of <asm/uaccess.h> Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Wang Weidong <wangweidong1@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-16tipc: kill unnecessary goto'swangweidong
Remove a number of needless 'goto exit' in send_stream when the socket is in an unconnected state. This patch is cosmetic and does not alter the operation of TIPC in any way. Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Wang Weidong <wangweidong1@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-16tipc: remove unnecessary variables and conditionswangweidong
We remove a number of unnecessary variables and branches in TIPC. This patch is cosmetic and does not change the operation of TIPC in any way. Reviewed-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: Wang Weidong <wangweidong1@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-11tipc: remove unused 'blocked' flag from tipc_link structYing Xue
In early versions of TIPC it was possible to administratively block individual links through the use of the member flag 'blocked'. This functionality was deemed redundant, and since commit 7368dd ("tipc: clean out all instances of #if 0'd unused code"), this flag has been unused. In the current code, a link only needs to be blocked for sending and reception if it is subject to an ongoing link failover. In that case, it is sufficient to check if the number of expected failover packets is non-zero, something which is done via the funtion 'link_blocked()'. This commit finally removes the redundant 'blocked' flag completely. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-11tipc: eliminate code duplication in media layerYing Xue
Currently TIPC supports two L2 media types, Ethernet and Infiniband. Because both these media are accessed through the common net_device API, several functions in the two media adaptation files turn out to be fully or almost identical, leading to unnecessary code duplication. In this commit we extract this common code from the two media files and move them to the generic bearer.c. Additionally, we change the function names to reflect their real role: to access L2 media, irrespective of type. Signed-off-by: Ying Xue <ying.xue@windriver.com> Cc: Patrick McHardy <kaber@trash.net> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-11tipc: relocate common functions from media to bearerYing Xue
Currently, registering a TIPC stack handler in the network device layer is done twice, once for Ethernet (eth_media) and Infiniband (ib_media) repectively. But, as this registration is not media specific, we can avoid some code duplication by moving the registering function to the generic bearer layer, to the file bearer.c, and call it only once. The same is true for the network device event notifier. As a side effect, the two workqueues we are using for for setting up/ cleaning up media can now be eliminated. Furthermore, the array for storing the specific media type structs, media_array[], can be entirely deleted. Note that the eth_started and ib_started flags were removed during the code relocation. There is now only one call to bearer_setup and bearer_cleanup, and these can logically not race against each other. Despite its size, this cleanup work incurs no functional changes in TIPC. In particular, it should be noted that the sequence ordering of received packets is unaffected by this change, since packet reception never was subject to any work queue handling in the first place. Signed-off-by: Ying Xue <ying.xue@windriver.com> Cc: Patrick McHardy <kaber@trash.net> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-11tipc: remove TIPC usage of field af_packet_priv in struct net_deviceYing Xue
TIPC is currently using the field 'af_packet_priv' in struct net_device as a handle to find the bearer instance associated to the given network device. But, by doing so it is blocking other networking cleanups, such as the one discussed here: http://patchwork.ozlabs.org/patch/178044/ This commit removes this usage from TIPC. Instead, we introduce a new field, 'tipc_ptr', to the net_device structure, to serve this purpose. When TIPC bearer is enabled, the bearer object is associated to 'tipc_ptr'. When a TIPC packet arrives in the recv_msg() upcall from a networking device, the bearer object can now be obtained from 'tipc_ptr'. When a bearer is disabled, the bearer object is detached from its underlying network device by setting 'tipc_ptr' to NULL. Additionally, an RCU lock is used to protect the new pointer. Henceforth, the existing tipc_net_lock is used in write mode to serialize write accesses to this pointer, while the new RCU lock is applied on the read side to ensure that the pointer is 100% valid within its wrapped area for all readers. Signed-off-by: Ying Xue <ying.xue@windriver.com> Cc: Patrick McHardy <kaber@trash.net> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-11tipc: improve naming and comment consistency in media layerJon Paul Maloy
struct 'tipc_media' represents the specific info that the media layer adaptors (eth_media and ib_media) expose to the generic bearer layer. We clarify this by improved commenting, and by giving the 'media_list' array the more appropriate name 'media_info_array'. There are no functional changes in this commit. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-11tipc: initiate media type array at compile timeJon Paul Maloy
Communication media types are abstracted through the struct 'tipc_media', one per media type. These structs are allocated statically inside their respective media file. Furthermore, in order to be able to reach all instances from a central location, we keep a static array with pointers to these structs. This array is currently initialized at runtime, under protection of tipc_net_lock. However, since the contents of the array itself never changes after initialization, we can just as well initialize it at compile time and make it 'const', at the same time making it obvious that no lock protection is needed here. This commit makes the array constant and removes the redundant lock protection. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-11tipc: eliminate redundant code with kfree_skb_list routineYing Xue
sk_buff lists are currently relased by looping over the list and explicitly releasing each buffer. We replace all occurrences of this loop with a call to kfree_skb_list(). Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10tipc: protect handler_enabled variable with qitem_lock spin lockYing Xue
'handler_enabled' is a global flag indicating whether the TIPC signal handling service is enabled or not. The lack of lock protection for this flag incurs a risk for contention, so that a tipc_k_signal() call might queue a signal handler to a destroyed signal queue, with unpredictable results. To correct this, we let the already existing 'qitem_lock' protect the flag, as it already does with the queue itself. This way, we ensure that the flag always is consistent across all cores. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10tipc: correct the order of stopping services at rmmodJon Paul Maloy
The 'signal handler' service in TIPC is a mechanism that makes it possible to postpone execution of functions, by launcing them into a job queue for execution in a separate tasklet, independent of the launching execution thread. When we do rmmod on the tipc module, this service is stopped after the network service. At the same time, the stopping of the network service may itself launch jobs for execution, with the risk that these functions may be scheduled for execution after the data structures meant to be accessed by the job have already been deleted. We have seen this happen, most often resulting in an oops. This commit ensures that the signal handler is the very first to be stopped when TIPC is shut down, so there are no surprises during the cleanup of the other services. Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-09tipc: remove interface state mirroring in bearerErik Hugne
struct 'tipc_bearer' is a generic representation of the underlying media type, and exists in a one-to-one relationship to each interface TIPC is using. The struct contains a 'blocked' flag that mirrors the operational and execution state of the represented interface, and is updated through notification calls from the latter. The users of tipc_bearer are checking this flag before each attempt to send a packet via the interface. This state mirroring serves no purpose in the current code base. TIPC links will not discover a media failure any faster through this mechanism, and in reality the flag only adds overhead at packet sending and reception. Furthermore, the fact that the flag needs to be protected by a spinlock aggregated into tipc_bearer has turned out to cause a serious and completely unnecessary deadlock problem. CPU0 CPU1 ---- ---- Time 0: bearer_disable() link_timeout() Time 1: spin_lock_bh(&b_ptr->lock) tipc_link_push_queue() Time 2: tipc_link_delete() tipc_bearer_blocked(b_ptr) Time 3: k_cancel_timer(&req->timer) spin_lock_bh(&b_ptr->lock) Time 4: del_timer_sync(&req->timer) I.e., del_timer_sync() on CPU0 never returns, because the timer handler on CPU1 is waiting for the bearer lock. We eliminate the 'blocked' flag from struct tipc_bearer, along with all tests on this flag. This not only resolves the deadlock, but also simplifies and speeds up the data path execution of TIPC. It also fits well into our ongoing effort to make the locking policy simpler and more manageable. An effect of this change is that we can get rid of functions such as tipc_bearer_blocked(), tipc_continue() and tipc_block_bearer(). We replace the latter with a new function, tipc_reset_bearer(), which resets all links associated to the bearer immediately after an interface goes down. A user might notice one slight change in link behaviour after this change. When an interface goes down, (e.g. through a NETDEV_DOWN event) all attached links will be reset immediately, instead of leaving it to each link to detect the failure through a timer-driven mechanism. We consider this an improvement, and see no obvious risks with the new behavior. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <Paul.Gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-20net: rework recvmsg handler msg_name and msg_namelen logicHannes Frederic Sowa
This patch now always passes msg->msg_namelen as 0. recvmsg handlers must set msg_namelen to the proper size <= sizeof(struct sockaddr_storage) to return msg_name to the user. This prevents numerous uninitialized memory leaks we had in the recvmsg handlers and makes it harder for new code to accidentally leak uninitialized memory. Optimize for the case recvfrom is called with NULL as address. We don't need to copy the address at all, so set it to NULL before invoking the recvmsg handler. We can do so, because all the recvmsg handlers must cope with the case a plain read() is called on them. read() also sets msg_name to NULL. Also document these changes in include/linux/net.h as suggested by David Miller. Changes since RFC: Set msg->msg_name = NULL if user specified a NULL in msg_name but had a non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't affect sendto as it would bail out earlier while trying to copy-in the address. It also more naturally reflects the logic by the callers of verify_iovec. With this change in place I could remove " if (!uaddr || msg_sys->msg_namelen == 0) msg->msg_name = NULL ". This change does not alter the user visible error logic as we ignore msg_namelen as long as msg_name is NULL. Also remove two unnecessary curly brackets in ___sys_recvmsg and change comments to netdev style. Cc: David Miller <davem@davemloft.net> Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-19genetlink: only pass array to genl_register_family_with_ops()Johannes Berg
As suggested by David Miller, make genl_register_family_with_ops() a macro and pass only the array, evaluating ARRAY_SIZE() in the macro, this is a little safer. The openvswitch has some indirection, assing ops/n_ops directly in that code. This might ultimately just assign the pointers in the family initializations, saving the struct genl_family_and_ops and code (once mcast groups are handled differently.) Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-15tipc: fix dereference before check warningErik Hugne
This fixes the following Smatch warning: net/tipc/link.c:2364 tipc_link_recv_fragment() warn: variable dereferenced before check '*head' (see line 2361) A null pointer might be passed to skb_try_coalesce if a malicious sender injects orphan fragments on a link. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-07tipc: reassembly failures should cause link resetErik Hugne
If appending a received fragment to the pending fragment chain in a unicast link fails, the current code tries to force a retransmission of the fragment by decrementing the 'next received sequence number' field in the link. This is done under the assumption that the failure is caused by an out-of-memory situation, an assumption that does not hold true after the previous patch in this series. A failure to append a fragment can now only be caused by a protocol violation by the sending peer, and it must hence be assumed that it is either malicious or buggy. Either way, the correct behavior is now to reset the link instead of trying to revert its sequence number. So, this is what we do in this commit. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-07tipc: message reassembly using fragment chainErik Hugne
When the first fragment of a long data data message is received on a link, a reassembly buffer large enough to hold the data from this and all subsequent fragments of the message is allocated. The payload of each new fragment is copied into this buffer upon arrival. When the last fragment is received, the reassembled message is delivered upwards to the port/socket layer. Not only is this an inefficient approach, but it may also cause bursts of reassembly failures in low memory situations. since we may fail to allocate the necessary large buffer in the first place. Furthermore, after 100 subsequent such failures the link will be reset, something that in reality aggravates the situation. To remedy this problem, this patch introduces a different approach. Instead of allocating a big reassembly buffer, we now append the arriving fragments to a reassembly chain on the link, and deliver the whole chain up to the socket layer once the last fragment has been received. This is safe because the retransmission layer of a TIPC link always delivers packets in strict uninterrupted order, to the reassembly layer as to all other upper layers. Hence there can never be more than one fragment chain pending reassembly at any given time in a link, and we can trust (but still verify) that the fragments will be chained up in the correct order. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-07tipc: don't reroute message fragmentsErik Hugne
When a message fragment is received in a broadcast or unicast link, the reception code will append the fragment payload to a big reassembly buffer through a call to the function tipc_recv_fragm(). However, after the return of that call, the logics goes on and passes the fragment buffer to the function tipc_net_route_msg(), which will simply drop it. This behavior is a remnant from the now obsolete multi-cluster functionality, and has no relevance in the current code base. Although currently harmless, this unnecessary call would be fatal after applying the next patch in this series, which introduces a completely new reassembly algorithm. So we change the code to eliminate the redundant call. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-30tipc: remove two indentation levels in tipc_recv_msg routineYing Xue
The message dispatching part of tipc_recv_msg() is wrapped layers of while/if/if/switch, causing out-of-control indentation and does not look very good. We reduce two indentation levels by separating the message dispatching from the blocks that checks link state and sequence numbers, allowing longer function and arg names to be consistently indented without wrapping. Additionally we also rename "cont" label to "discard" and add one new label called "unlock_discard" to make code clearer. In all, these are cosmetic changes that do not alter the operation of TIPC in any way. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Erik Hugne <erik.hugne@ericsson.com> Cc: David Laight <david.laight@aculab.com> Cc: Andreas Bofjäll <andreas.bofjall@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-19net: misc: Remove extern from function prototypesJoe Perches
There are a mix of function prototypes with and without extern in the kernel sources. Standardize on not using extern for function prototypes. Function prototypes don't need to be written with extern. extern is assumed by the compiler. Its use is as unnecessary as using auto to declare automatic/local variables in a block. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-18tipc: simplify the link lookup routineErik Hugne
When checking statistics or changing parameters on a link, the link_find_link function is used to locate the link with a given name. The complex method of deconstructing the name into local and remote address/interface is error prone and may fail if the interface names contains special characters. We change the lookup method to iterate over the list of nodes and compare the link names. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-18tipc: correct return value of link_cmd_set_value routineYing Xue
link_cmd_set_value() takes commands for link, bearer and media related configuration. Genereally the function returns 0 when a command is recognized, and -EINVAL when it is not. However, in the switch for link related commands it returns 0 even when the command is unrecognized. This will sometimes make it look as if a failed configuration command has been successful, but has otherwise no negative effects. We remove this anomaly by returning -EINVAL even for link commands. We also rework all three switches to make them conforming to common kernel coding style. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-18tipc: correct return value of recv_msg routineYing Xue
Currently, rcv_msg() always returns zero on a packet delivery upcall from net_device. To make its behavior more compliant with the way this API should be used, we change this to let it return NET_RX_SUCCESS (which is zero anyway) when it is able to handle the packet, and NET_RX_DROP otherwise. The latter does not imply any functional change, it only enables the driver to keep more accurate statistics about the fate of delivered packets. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-18tipc: avoid unnecessary lookup for tipc bearer instanceYing Xue
tipc_block_bearer() currently takes a bearer name (const char*) as argument. This requires the function to make a lookup to find the pointer to the corresponding bearer struct. In the current code base this is not necessary, since the only two callers (tipc_continue(),recv_notification()) already have validated copies of this pointer, and hence can pass it directly in the function call. We change tipc_block_bearer() to directly take struct tipc_bearer* as argument instead. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-18tipc: make bearer and media naming consistentYing Xue
TIPC 'bearer' exists as an abstract concept, while 'media' is deemed a specific implementation of a bearer, such as Ethernet or Infiniband media. When a component inside TIPC wants to control a specific media, it only needs to access the generic bearer API to achieve this. However, in the current media implementations, the 'bearer' name is also extensively used in media specific function and variable names. This may create confusion, so we choose to replace the term 'bearer' with 'media' in all function names, variable names, and prefixes where this is what really is meant. Note that this change is cosmetic only, and no runtime behaviour changes are made here. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-18tipc: silence sparse warningsYing Xue
Eliminate below sparse warnings: net/tipc/link.c:1210:37: warning: cast removes address space of expression net/tipc/link.c:1218:59: warning: incorrect type in argument 2 (different address spaces) net/tipc/link.c:1218:59: expected void const [noderef] <asn:1>*from net/tipc/link.c:1218:59: got unsigned char const [usertype] *[assigned] sect_crs net/tipc/socket.c:341:49: warning: Using plain integer as NULL pointer net/tipc/socket.c:1371:36: warning: Using plain integer as NULL pointer net/tipc/socket.c:1694:57: warning: Using plain integer as NULL pointer Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: Andreas Bofjäll <andreas.bofjall@ericsson.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-18tipc: remove iovec length parameter from all sending functionsYing Xue
tipc_msg_build() now copies message data from iovec to skb_buff using memcpy_fromiovecend(), which doesn't need to be passed the iovec length to perform the copying. So we remove the parameter indicating iovec length in all functions where TIPC messages are built and sent. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-18tipc: don't use memcpy to copy from user spaceYing Xue
tipc_msg_build() calls skb_copy_to_linear_data_offset() to copy data from user space to kernel space. However, the latter function does in its turn call memcpy() to perform the actual copying. This poses an obvious security and robustness risk, since memcpy() never makes any validity check on the pointer it is copying from. To correct this, we the replace the offending function call with a call to memcpy_fromiovecend(), which uses copy_from_user() to perform the copying. Signed-off-by: Ying Xue <ying.xue@windriver.com> Reviewed-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Jon Maloy <jon.maloy@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-30tipc: set sk_err correctly when connection failsErik Hugne
Should a connect fail, if the publication/server is unavailable or due to some other error, a positive value will be returned and errno is never set. If the application code checks for an explicit zero return from connect (success) or a negative return (failure), it will not catch the error and subsequent send() calls will fail as shown from the strace snippet below. socket(0x1e /* PF_??? */, SOCK_SEQPACKET, 0) = 3 connect(3, {sa_family=0x1e /* AF_??? */, sa_data="\2\1\322\4\0\0\322\4\0\0\0\0\0\0"}, 16) = 111 sendto(3, "test", 4, 0, NULL, 0) = -1 EPIPE (Broken pipe) The reason for this behaviour is that TIPC wrongly inverts error codes set in sk_err. Signed-off-by: Erik Hugne <erik.hugne@ericsson.com> Signed-off-by: David S. Miller <davem@davemloft.net>