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* net: fix skb use after free in netpollFeng Sun2019-09-101-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 2c1644cf6d46a8267d79ed95cb9b563839346562 ] After commit baeababb5b85d5c4e6c917efe2a1504179438d3b ("tun: return NET_XMIT_DROP for dropped packets"), when tun_net_xmit drop packets, it will free skb and return NET_XMIT_DROP, netpoll_send_skb_on_dev will run into following use after free cases: 1. retry netpoll_start_xmit with freed skb; 2. queue freed skb in npinfo->txq. queue_process will also run into use after free case. hit netpoll_send_skb_on_dev first case with following kernel log: [ 117.864773] kernel BUG at mm/slub.c:306! [ 117.864773] invalid opcode: 0000 [#1] SMP PTI [ 117.864774] CPU: 3 PID: 2627 Comm: loop_printmsg Kdump: loaded Tainted: P OE 5.3.0-050300rc5-generic #201908182231 [ 117.864775] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014 [ 117.864775] RIP: 0010:kmem_cache_free+0x28d/0x2b0 [ 117.864781] Call Trace: [ 117.864781] ? tun_net_xmit+0x21c/0x460 [ 117.864781] kfree_skbmem+0x4e/0x60 [ 117.864782] kfree_skb+0x3a/0xa0 [ 117.864782] tun_net_xmit+0x21c/0x460 [ 117.864782] netpoll_start_xmit+0x11d/0x1b0 [ 117.864788] netpoll_send_skb_on_dev+0x1b8/0x200 [ 117.864789] __br_forward+0x1b9/0x1e0 [bridge] [ 117.864789] ? skb_clone+0x53/0xd0 [ 117.864790] ? __skb_clone+0x2e/0x120 [ 117.864790] deliver_clone+0x37/0x50 [bridge] [ 117.864790] maybe_deliver+0x89/0xc0 [bridge] [ 117.864791] br_flood+0x6c/0x130 [bridge] [ 117.864791] br_dev_xmit+0x315/0x3c0 [bridge] [ 117.864792] netpoll_start_xmit+0x11d/0x1b0 [ 117.864792] netpoll_send_skb_on_dev+0x1b8/0x200 [ 117.864792] netpoll_send_udp+0x2c6/0x3e8 [ 117.864793] write_msg+0xd9/0xf0 [netconsole] [ 117.864793] console_unlock+0x386/0x4e0 [ 117.864793] vprintk_emit+0x17e/0x280 [ 117.864794] vprintk_default+0x29/0x50 [ 117.864794] vprintk_func+0x4c/0xbc [ 117.864794] printk+0x58/0x6f [ 117.864795] loop_fun+0x24/0x41 [printmsg_loop] [ 117.864795] kthread+0x104/0x140 [ 117.864795] ? 0xffffffffc05b1000 [ 117.864796] ? kthread_park+0x80/0x80 [ 117.864796] ret_from_fork+0x35/0x40 Signed-off-by: Feng Sun <loyou85@gmail.com> Signed-off-by: Xiaojun Zhao <xiaojunzhao141@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Revert "bond: take rcu lock in netpoll_send_skb_on_dev"David S. Miller2018-10-191-2/+0
| | | | | | | | | This reverts commit 6fe9487892b32cb1c8b8b0d552ed7222a527fe30. It is causing more serious regressions than the RCU warning it is fixing. Signed-off-by: David S. Miller <davem@davemloft.net>
* bond: take rcu lock in netpoll_send_skb_on_devDave Jones2018-10-011-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The bonding driver lacks the rcu lock when it calls down into netdev_lower_get_next_private_rcu from bond_poll_controller, which results in a trace like: WARNING: CPU: 2 PID: 179 at net/core/dev.c:6567 netdev_lower_get_next_private_rcu+0x34/0x40 CPU: 2 PID: 179 Comm: kworker/u16:15 Not tainted 4.19.0-rc5-backup+ #1 Workqueue: bond0 bond_mii_monitor RIP: 0010:netdev_lower_get_next_private_rcu+0x34/0x40 Code: 48 89 fb e8 fe 29 63 ff 85 c0 74 1e 48 8b 45 00 48 81 c3 c0 00 00 00 48 8b 00 48 39 d8 74 0f 48 89 45 00 48 8b 40 f8 5b 5d c3 <0f> 0b eb de 31 c0 eb f5 0f 1f 40 00 0f 1f 44 00 00 48 8> RSP: 0018:ffffc9000087fa68 EFLAGS: 00010046 RAX: 0000000000000000 RBX: ffff880429614560 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 00000000ffffffff RDI: ffffffffa184ada0 RBP: ffffc9000087fa80 R08: 0000000000000001 R09: 0000000000000000 R10: ffffc9000087f9f0 R11: ffff880429798040 R12: ffff8804289d5980 R13: ffffffffa1511f60 R14: 00000000000000c8 R15: 00000000ffffffff FS: 0000000000000000(0000) GS:ffff88042f880000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4b78fce180 CR3: 000000018180f006 CR4: 00000000001606e0 Call Trace: bond_poll_controller+0x52/0x170 netpoll_poll_dev+0x79/0x290 netpoll_send_skb_on_dev+0x158/0x2c0 netpoll_send_udp+0x2d5/0x430 write_ext_msg+0x1e0/0x210 console_unlock+0x3c4/0x630 vprintk_emit+0xfa/0x2f0 printk+0x52/0x6e ? __netdev_printk+0x12b/0x220 netdev_info+0x64/0x80 ? bond_3ad_set_carrier+0xe9/0x180 bond_select_active_slave+0x1fc/0x310 bond_mii_monitor+0x709/0x9b0 process_one_work+0x221/0x5e0 worker_thread+0x4f/0x3b0 kthread+0x100/0x140 ? process_one_work+0x5e0/0x5e0 ? kthread_delayed_work_timer_fn+0x90/0x90 ret_from_fork+0x24/0x30 We're also doing rcu dereferences a layer up in netpoll_send_skb_on_dev before we call down into netpoll_poll_dev, so just take the lock there. Suggested-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: do not test NAPI_STATE_SCHED in poll_one_napi()Eric Dumazet2018-09-281-19/+1
| | | | | | | | | | | | | | | | | | | | Since we do no longer require NAPI drivers to provide an ndo_poll_controller(), napi_schedule() has not been done before poll_one_napi() invocation. So testing NAPI_STATE_SCHED is likely to cause early returns. While we are at it, remove outdated comment. Note to future bisections : This change might surface prior bugs in drivers. See commit 73f21c653f93 ("bnxt_en: Fix TX timeout during netpoll.") for one occurrence. Fixes: ac3d9dd034e5 ("netpoll: make ndo_poll_controller() optional") Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Song Liu <songliubraving@fb.com> Cc: Michael Chan <michael.chan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: make ndo_poll_controller() optionalEric Dumazet2018-09-231-12/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | As diagnosed by Song Liu, ndo_poll_controller() can be very dangerous on loaded hosts, since the cpu calling ndo_poll_controller() might steal all NAPI contexts (for all RX/TX queues of the NIC). This capture can last for unlimited amount of time, since one cpu is generally not able to drain all the queues under load. It seems that all networking drivers that do use NAPI for their TX completions, should not provide a ndo_poll_controller(). NAPI drivers have netpoll support already handled in core networking stack, since netpoll_poll_dev() uses poll_napi(dev) to iterate through registered NAPI contexts for a device. This patch allows netpoll_poll_dev() to process NAPI contexts even for drivers not providing ndo_poll_controller(), allowing for following patches in NAPI drivers. Also we export netpoll_poll_dev() so that it can be called by bonding/team drivers in following patches. Reported-by: Song Liu <songliubraving@fb.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Song Liu <songliubraving@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Use lockdep to assert IRQs are disabled/enabledFrederic Weisbecker2017-11-081-1/+1
| | | | | | | | | | | | | | | | | Use lockdep to check that IRQs are enabled or disabled as expected. This way the sanity check only shows overhead when concurrency correctness debug code is enabled. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: David S. Miller <davem@davemloft.net> Cc: Lai Jiangshan <jiangshanlai@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tejun Heo <tj@kernel.org> Link: http://lkml.kernel.org/r/1509980490-4285-14-git-send-email-frederic@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* netpoll: Fix device name check in netpoll_setup()Matthias Kaehlcke2017-07-261-1/+1
| | | | | | | | | | | | | | | Apparently netpoll_setup() assumes that netpoll.dev_name is a pointer when checking if the device name is set: if (np->dev_name) { ... However the field is a character array, therefore the condition always yields true. Check instead whether the first byte of the array has a non-zero value. Signed-off-by: Matthias Kaehlcke <mka@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: shut up a kernel warning on refcountWANG Cong2017-07-141-1/+1
| | | | | | | | | | | | | | | When we convert atomic_t to refcount_t, a new kernel warning on "increment on 0" is introduced in the netpoll code, zap_completion_queue(). In fact for this special case, we know the refcount is 0 and we just have to set it to 1 to satisfy the following dev_kfree_skb_any(), so we can just use refcount_set(..., 1) instead. Fixes: 633547973ffc ("net: convert sk_buff.users from atomic_t to refcount_t") Reported-by: Dave Jones <davej@codemonkey.org.uk> Cc: Reshetova, Elena <elena.reshetova@intel.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: convert netpoll_info.refcnt from atomic_t to refcount_tReshetova, Elena2017-07-011-3/+3
| | | | | | | | | | | | | | refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: convert sk_buff.users from atomic_t to refcount_tReshetova, Elena2017-07-011-2/+2
| | | | | | | | | | | | | | refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* networking: make skb_push & __skb_push return void pointersJohannes Berg2017-06-161-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It seems like a historic accident that these return unsigned char *, and in many places that means casts are required, more often than not. Make these functions return void * and remove all the casts across the tree, adding a (u8 *) cast only where the unsigned char pointer was used directly, all done with the following spatch: @@ expression SKB, LEN; typedef u8; identifier fn = { skb_push, __skb_push, skb_push_rcsum }; @@ - *(fn(SKB, LEN)) + *(u8 *)fn(SKB, LEN) @@ expression E, SKB, LEN; identifier fn = { skb_push, __skb_push, skb_push_rcsum }; type T; @@ - E = ((T *)(fn(SKB, LEN))) + E = fn(SKB, LEN) @@ expression SKB, LEN; identifier fn = { skb_push, __skb_push, skb_push_rcsum }; @@ - fn(SKB, LEN)[0] + *(u8 *)fn(SKB, LEN) Note that the last part there converts from push(...)[0] to the more idiomatic *(u8 *)push(...). Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Check for skb->queue_mappingTushar Dave2017-04-211-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reducing real_num_tx_queues needs to be in sync with skb queue_mapping otherwise skbs with queue_mapping greater than real_num_tx_queues can be sent to the underlying driver and can result in kernel panic. One such event is running netconsole and enabling VF on the same device. Or running netconsole and changing number of tx queues via ethtool on same device. e.g. Unable to handle kernel NULL pointer dereference tsk->{mm,active_mm}->context = 0000000000001525 tsk->{mm,active_mm}->pgd = fff800130ff9a000 \|/ ____ \|/ "@'/ .. \`@" /_| \__/ |_\ \__U_/ kworker/48:1(475): Oops [#1] CPU: 48 PID: 475 Comm: kworker/48:1 Tainted: G OE 4.11.0-rc3-davem-net+ #7 Workqueue: events queue_process task: fff80013113299c0 task.stack: fff800131132c000 TSTATE: 0000004480e01600 TPC: 00000000103f9e3c TNPC: 00000000103f9e40 Y: 00000000 Tainted: G OE TPC: <ixgbe_xmit_frame_ring+0x7c/0x6c0 [ixgbe]> g0: 0000000000000000 g1: 0000000000003fff g2: 0000000000000000 g3: 0000000000000001 g4: fff80013113299c0 g5: fff8001fa6808000 g6: fff800131132c000 g7: 00000000000000c0 o0: fff8001fa760c460 o1: fff8001311329a50 o2: fff8001fa7607504 o3: 0000000000000003 o4: fff8001f96e63a40 o5: fff8001311d77ec0 sp: fff800131132f0e1 ret_pc: 000000000049ed94 RPC: <set_next_entity+0x34/0xb80> l0: 0000000000000000 l1: 0000000000000800 l2: 0000000000000000 l3: 0000000000000000 l4: 000b2aa30e34b10d l5: 0000000000000000 l6: 0000000000000000 l7: fff8001fa7605028 i0: fff80013111a8a00 i1: fff80013155a0780 i2: 0000000000000000 i3: 0000000000000000 i4: 0000000000000000 i5: 0000000000100000 i6: fff800131132f1a1 i7: 00000000103fa4b0 I7: <ixgbe_xmit_frame+0x30/0xa0 [ixgbe]> Call Trace: [00000000103fa4b0] ixgbe_xmit_frame+0x30/0xa0 [ixgbe] [0000000000998c74] netpoll_start_xmit+0xf4/0x200 [0000000000998e10] queue_process+0x90/0x160 [0000000000485fa8] process_one_work+0x188/0x480 [0000000000486410] worker_thread+0x170/0x4c0 [000000000048c6b8] kthread+0xd8/0x120 [0000000000406064] ret_from_fork+0x1c/0x2c [0000000000000000] (null) Disabling lock debugging due to kernel taint Caller[00000000103fa4b0]: ixgbe_xmit_frame+0x30/0xa0 [ixgbe] Caller[0000000000998c74]: netpoll_start_xmit+0xf4/0x200 Caller[0000000000998e10]: queue_process+0x90/0x160 Caller[0000000000485fa8]: process_one_work+0x188/0x480 Caller[0000000000486410]: worker_thread+0x170/0x4c0 Caller[000000000048c6b8]: kthread+0xd8/0x120 Caller[0000000000406064]: ret_from_fork+0x1c/0x2c Caller[0000000000000000]: (null) Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: more efficient lockingEric Dumazet2016-11-161-3/+3
| | | | | | | | | | | | | | | | | Callers of netpoll_poll_lock() own NAPI_STATE_SCHED Callers of netpoll_poll_unlock() have BH blocked between the NAPI_STATE_SCHED being cleared and poll_lock is released. We can avoid the spinlock which has no contention, and use cmpxchg() on poll_owner which we need to set anyway. This removes a possible lockdep violation after the cited commit, since sk_busy_loop() re-enables BH before calling busy_poll_stop() Fixes: 217f69743681 ("net: busy-poll: allow preemption in sk_busy_loop()") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: tracepoint napi:napi_poll add work and budgetJesper Dangaard Brouer2016-07-091-1/+1
| | | | | | | | | | | | | An important information for the napi_poll tracepoint is knowing the work done (packets processed) by the napi_poll() call. Add both the work done and budget, as they are related. Handle trace_napi_poll() param change in dropwatch/drop_monitor and in python perf script netdev-times.py in backward compat way, as python fortunately supports optional parameter handling. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Revert "netpoll: Fix extra refcount release in netpoll_cleanup()"Bjorn Helgaas2016-04-051-2/+1
| | | | | | | | | | | This reverts commit 543e3a8da5a4c453e992d5351ef405d5e32f27d7. Direct callers of __netpoll_setup() depend on it to set np->dev, so we can't simply move that assignment up to netpoll_stup(). Reported-by: Bart Van Assche <bart.vanassche@sandisk.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Fix extra refcount release in netpoll_cleanup()Bjorn Helgaas2016-03-251-1/+2
| | | | | | | | | | | | | | | | | | | netpoll_setup() does a dev_hold() on np->dev, the netpoll device. If it fails, it correctly does a dev_put() but leaves np->dev set. If we call netpoll_cleanup() after the failure, np->dev is still set so we do another dev_put(), which decrements the refcount an extra time. It's questionable to call netpoll_cleanup() after netpoll_setup() fails, but it can be difficult to find the problem, and we can easily avoid it in this case. The extra decrements can lead to hangs like this: unregister_netdevice: waiting for bond0 to become free. Usage count = -3 Set and clear np->dev at the points where we dev_hold() and dev_put() the device. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Drop budget parameter from NAPI polling call hierarchyAlexander Duyck2015-09-291-12/+11
| | | | | | | | | | | | | | | | | | | | | | | For some reason we were carrying the budget value around between the various calls to napi->poll. If for example one of the drivers called had a bug in which it returned a non-zero value for work this could result in the budget value becoming negative. Rather than carry around a value of budget that is 0 or less we can instead just loop through and pass 0 to each napi->poll call. If any driver returns a value for work done that is non-zero then we can report that driver and continue rather than allowing a bad actor to make the budget value negative and pass that negative value to napi->poll. Note, the only actual change here is that instead of letting budget become negative we are keeping it at 0 regardless of the value returned for work since it should not be possible for the polling routine to do any actual work with a budget of 0. So if the polling routine returns a non-0 value we are just reporting it and continuing with a budget of 0 rather than letting that work value be subtracted from the budget of 0. Signed-off-by: Alexander Duyck <aduyck@mirantis.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Close race condition between poll_one_napi and napi_disableNeil Horman2015-09-231-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Drivers might call napi_disable while not holding the napi instance poll_lock. In those instances, its possible for a race condition to exist between poll_one_napi and napi_disable. That is to say, poll_one_napi only tests the NAPI_STATE_SCHED bit to see if there is work to do during a poll, and as such the following may happen: CPU0 CPU1 ndo_tx_timeout napi_poll_dev napi_disable poll_one_napi test_and_set_bit (ret 0) test_bit (ret 1) reset adapter napi_poll_routine If the adapter gets a tx timeout without a napi instance scheduled, its possible for the adapter to think it has exclusive access to the hardware (as the napi instance is now scheduled via the napi_disable call), while the netpoll code thinks there is simply work to do. The result is parallel hardware access leading to corrupt data structures in the driver, and a crash. Additionaly, there is another, more critical race between netpoll and napi_disable. The disabled napi state is actually identical to the scheduled state for a given napi instance. The implication being that, if a napi instance is disabled, a netconsole instance would see the napi state of the device as having been scheduled, and poll it, likely while the driver was dong something requiring exclusive access. In the case above, its fairly clear that not having the rings in a state ready to be polled will cause any number of crashes. The fix should be pretty easy. netpoll uses its own bit to indicate that that the napi instance is in a state of being serviced by netpoll (NAPI_STATE_NPSVC). We can just gate disabling on that bit as well as the sched bit. That should prevent netpoll from conducting a napi poll if we convert its set bit to a test_and_set_bit operation to provide mutual exclusion Change notes: V2) Remove a trailing whtiespace Resubmit with proper subject prefix V3) Clean up spacing nits Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: "David S. Miller" <davem@davemloft.net> CC: jmaxwell@redhat.com Tested-by: jmaxwell@redhat.com Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: warn on netpoll_send_udp users who haven't disabled irqsNikolay Aleksandrov2015-08-281-0/+2
| | | | | | | | Make sure we catch future netpoll_send_udp users who use it without disabling irqs and also as a hint for poll_controller users. Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: rename vlan_tx_* helpers since "tx" is misleading thereJiri Pirko2015-01-131-1/+1
| | | | | | | The same macros are used for rx as well. So rename it. Signed-off-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net>
* vlan: introduce *vlan_hwaccel_push_inside helpersJiri Pirko2014-11-211-3/+1
| | | | | | | | | Use them to push skb->vlan_tci into the payload and avoid code duplication. Signed-off-by: Jiri Pirko <jiri@resnulli.us> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* vlan: rename __vlan_put_tag to vlan_insert_tag_set_protoJiri Pirko2014-11-211-2/+2
| | | | | | | | | Name fits better. Plus there's going to be introduced __vlan_insert_tag later on. Signed-off-by: Jiri Pirko <jiri@resnulli.us> Acked-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Pass a "more" indication down into netdev_start_xmit() code paths.David S. Miller2014-09-011-1/+1
| | | | | | For now it will always be false. Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Do txq_trans_update() in netdev_start_xmit()David S. Miller2014-09-011-3/+1
| | | | | | | That way we don't have to audit every call site to make sure it is doing this properly. Signed-off-by: David S. Miller <davem@davemloft.net>
* net: add skb_get_tx_queue() helperDaniel Borkmann2014-08-291-1/+1
| | | | | | | | Replace occurences of skb_get_queue_mapping() and follow-up netdev_get_tx_queue() with an actual helper function. Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Add ops->ndo_xmit_flush()David S. Miller2014-08-241-2/+1
| | | | Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: fix use after freedavid decotigny2014-07-081-1/+2
| | | | | | | | | | After a bonding master reclaims the netpoll info struct, slaves could still hold a pointer to the reclaimed data. This patch fixes it: as soon as netpoll_async_cleanup is called for a slave (eg. when un-enslaved), we make sure that this slave doesn't point to the data. Signed-off-by: David Decotigny <decot@googlers.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Use skb_irq_freeable to make zap_completion_queue safe.Eric W. Biederman2014-04-011-1/+1
| | | | | | | | | | Replace the test in zap_completion_queue to test when it is safe to free skbs in hard irq context with skb_irq_freeable ensuring we only free skbs when it is safe, and removing the possibility of subtle problems. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Respect NETIF_F_LLTXEric W. Biederman2014-03-291-5/+5
| | | | | | | | | | | | | | | | Stop taking the transmit lock when a network device has specified NETIF_F_LLTX. If no locks needed to trasnmit a packet this is the ideal scenario for netpoll as all packets can be trasnmitted immediately. Even if some locks are needed in ndo_start_xmit skipping any unnecessary serialization is desirable for netpoll as it makes it more likely a debugging packet may be trasnmitted immediately instead of being deferred until later. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Remove strong unnecessary assumptions about skbsEric W. Biederman2014-03-291-2/+2
| | | | | | | | | | | | | | Remove the assumption that the skbs that make it to netpoll_send_skb_on_dev are allocated with find_skb, such that skb->users == 1 and nothing is attached that would prevent the skbs from being freed from hard irq context. Remove this assumption by replacing __kfree_skb on error paths with dev_kfree_skb_irq (in hard irq context) and kfree_skb (in process context). Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Rename netpoll_rx_enable/disable to netpoll_poll_disable/enableEric W. Biederman2014-03-291-4/+4
| | | | | | | | | | | The netpoll_rx_enable and netpoll_rx_disable functions have always controlled polling the network drivers transmit and receive queues. Rename them to netpoll_poll_enable and netpoll_poll_disable to make their functionality clear. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Only call ndo_start_xmit from a single placeEric W. Biederman2014-03-291-25/+36
| | | | | | | | | | | | | | | | | Factor out the code that needs to surround ndo_start_xmit from netpoll_send_skb_on_dev into netpoll_start_xmit. It is an unfortunate fact that as the netpoll code has been maintained the primary call site ndo_start_xmit learned how to handle vlans and timestamps but the second call of ndo_start_xmit in queue_process did not. With the introduction of netpoll_start_xmit this associated logic now happens at both call sites of ndo_start_xmit and should make it easy for that to continue into the future. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Remove gfp parameter from __netpoll_setupEric W. Biederman2014-03-291-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The gfp parameter was added in: commit 47be03a28cc6c80e3aa2b3e8ed6d960ff0c5c0af Author: Amerigo Wang <amwang@redhat.com> Date: Fri Aug 10 01:24:37 2012 +0000 netpoll: use GFP_ATOMIC in slave_enable_netpoll() and __netpoll_setup() slave_enable_netpoll() and __netpoll_setup() may be called with read_lock() held, so should use GFP_ATOMIC to allocate memory. Eric suggested to pass gfp flags to __netpoll_setup(). Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Cong Wang <amwang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> The reason for the gfp parameter was removed in: commit c4cdef9b7183159c23c7302aaf270d64c549f557 Author: dingtianhong <dingtianhong@huawei.com> Date: Tue Jul 23 15:25:27 2013 +0800 bonding: don't call slave_xxx_netpoll under spinlocks The slave_xxx_netpoll will call synchronize_rcu_bh(), so the function may schedule and sleep, it should't be called under spinlocks. bond_netpoll_setup() and bond_netpoll_cleanup() are always protected by rtnl lock, it is no need to take the read lock, as the slave list couldn't be changed outside rtnl lock. Signed-off-by: Ding Tianhong <dingtianhong@huawei.com> Cc: Jay Vosburgh <fubar@us.ibm.com> Cc: Andy Gospodarek <andy@greyhouse.net> Signed-off-by: David S. Miller <davem@davemloft.net> Nothing else that calls __netpoll_setup or ndo_netpoll_setup requires a gfp paramter, so remove the gfp parameter from both of these functions making the code clearer. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net/core: Use RCU_INIT_POINTER(x, NULL) in netpoll.cMonam Agarwal2014-03-271-1/+1
| | | | | | | | | | | | This patch replaces rcu_assign_pointer(x, NULL) with RCU_INIT_POINTER(x, NULL) The rcu_assign_pointer() ensures that the initialization of a structure is carried out before storing a pointer to that structure. And in the case of the NULL pointer, there is no structure to initialize. So, rcu_assign_pointer(p, NULL) can be safely converted to RCU_INIT_POINTER(p, NULL) Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Remove dead packet receive code (CONFIG_NETPOLL_TRAP)Eric W. Biederman2014-03-171-519/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | The netpoll packet receive code only becomes active if the netpoll rx_skb_hook is implemented, and there is not a single implementation of the netpoll rx_skb_hook in the kernel. All of the out of tree implementations I have found all call netpoll_poll which was removed from the kernel in 2011, so this change should not add any additional breakage. There are problems with the netpoll packet receive code. __netpoll_rx does not call dev_kfree_skb_irq or dev_kfree_skb_any in hard irq context. netpoll_neigh_reply leaks every skb it receives. Reception of packets does not work successfully on stacked devices (aka bonding, team, bridge, and vlans). Given that the netpoll packet receive code is buggy, there are no out of tree users that will be merged soon, and the code has not been used for in tree for a decade let's just remove it. Reverting this commit can server as a starting point for anyone who wants to resurrect netpoll packet reception support. Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Move all receive processing under CONFIG_NETPOLL_TRAPEric W. Biederman2014-03-171-17/+64
| | | | | | | | | | | | | | | | | | | | | Make rx_skb_hook, and rx in struct netpoll depend on CONFIG_NETPOLL_TRAP Make rx_lock, rx_np, and neigh_tx in struct netpoll_info depend on CONFIG_NETPOLL_TRAP Make the functions netpoll_rx_on, netpoll_rx, and netpoll_receive_skb no-ops when CONFIG_NETPOLL_TRAP is not set. Only build netpoll_neigh_reply, checksum_udp service_neigh_queue, pkt_is_ns, and __netpoll_rx when CONFIG_NETPOLL_TRAP is defined. Add helper functions netpoll_trap_setup, netpoll_trap_setup_info, netpoll_trap_cleanup, and netpoll_trap_cleanup_info that initialize and cleanup the struct netpoll and struct netpoll_info receive specific fields when CONFIG_NETPOLL_TRAP is enabled and do nothing otherwise. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Consolidate neigh_tx processing in service_neigh_queueEric W. Biederman2014-03-171-22/+16
| | | | | | | | | | | Move the bond slave device neigh_tx handling into service_neigh_queue. In connection with neigh_tx processing remove unnecessary tests of a NULL netpoll_info. As the netpoll_poll_dev has already used and thus verified the existince of the netpoll_info. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Move netpoll_trap under CONFIG_NETPOLL_TRAPEric W. Biederman2014-03-171-5/+9
| | | | | | | | | | | | Now that we no longer need to receive packets to safely drain the network drivers receive queue move netpoll_trap and netpoll_set_trap under CONFIG_NETPOLL_TRAP Making netpoll_trap and netpoll_set_trap noop inline functions when CONFIG_NETPOLL_TRAP is not set. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Don't drop all received packets.Eric W. Biederman2014-03-171-11/+6
| | | | | | | | | | | | | | | | | | | | Change the strategy of netpoll from dropping all packets received during netpoll_poll_dev to calling napi poll with a budget of 0 (to avoid processing drivers rx queue), and to ignore packets received with netif_rx (those will safely be placed on the backlog queue). All of the netpoll supporting drivers have been reviewed to ensure either thay use netif_rx or that a budget of 0 is supported by their napi poll routine and that a budget of 0 will not process the drivers rx queues. Not dropping packets makes NETPOLL_RX_DROP unnecesary so it is removed. npinfo->rx_flags is removed as rx_flags with just the NETPOLL_RX_ENABLED flag becomes just a redundant mirror of list_empty(&npinfo->rx_np). Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Add netpoll_rx_processingEric W. Biederman2014-03-171-2/+2
| | | | | | | | Add a helper netpoll_rx_processing that reports when netpoll has receive side processing to perform. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Warn if more packets are processed than are budgetedEric W. Biederman2014-03-171-0/+1
| | | | | | | | | | | | | | There is already a warning for this case in the normal netpoll path, but put a copy here in case how netpoll calls the poll functions causes a differenet result. netpoll will shortly call the napi poll routine with a budget 0 to avoid any rx packets being processed. As nothing does that today we may encounter drivers that have problems so a netpoll specific warning seems desirable. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Visit all napi handlers in poll_napiEric W. Biederman2014-03-171-3/+0
| | | | | | | | | In poll_napi loop through all of the napi handlers even when the budget falls to 0 to ensure that we process all of the tx_queues, and so that we continue to call into drivers when our initial budget is 0. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Pass budget into poll_napiEric W. Biederman2014-03-171-3/+3
| | | | | | | | | This moves the control logic to the top level in netpoll_poll_dev instead of having it dispersed throughout netpoll_poll_dev, poll_napi and poll_one_napi. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: move setting of NETPOLL_RX_DROP into netpoll_poll_devEric W. Biederman2014-03-171-8/+8
| | | | | | | | | | | | Today netpoll depends on setting NETPOLL_RX_DROP before networking drivers receive packets in interrupt context so that the packets can be dropped. Move this setting into netpoll_poll_dev from poll_one_napi so that if ndo_poll_controller happens to receive packets we will drop the packets on the floor instead of letting the packets bounce through the networking stack and potentially cause problems. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: fix netconsole IPv6 setupSabrina Dubroca2014-02-061-1/+3
| | | | | | | | | | | | | | Currently, to make netconsole start over IPv6, the source address needs to be specified. Without a source address, netpoll_parse_options assumes we're setting up over IPv4 and the destination IPv6 address is rejected. Check if the IP version has been forced by a source address before checking for a version mismatch when parsing the destination address. Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Acked-by: Cong Wang <cwang@twopensource.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Use ether_addr_copyJoe Perches2014-01-211-2/+2
| | | | | | | | Use ether_addr_copy instead of memcpy(a, b, ETH_ALEN) to save some cycles on arm and powerpc. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: core: explicitly select a txq before doing l2 forwardingJason Wang2014-01-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The will cause several issues: - NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan instead of lower device which misses the necessary txq synchronization for lower device such as txq stopping or frozen required by dev watchdog or control path. - dev_hard_start_xmit() was called with NULL txq which bypasses the net device watchdog. - dev_hard_start_xmit() does not check txq everywhere which will lead a crash when tso is disabled for lower device. Fix this by explicitly introducing a new param for .ndo_select_queue() for just selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also extended to accept this parameter and dev_queue_xmit_accel() was used to do l2 forwarding transmission. With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of dev_queue_xmit() to do the transmission. In the future, it was also required for macvtap l2 forwarding support since it provides a necessary synchronization method. Cc: John Fastabend <john.r.fastabend@intel.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: e1000-devel@lists.sourceforge.net Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: John Fastabend <john.r.fastabend@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Fix missing TXQ unlock and and OOPS.David S. Miller2014-01-021-2/+9
| | | | | | | | | | | The VLAN tag handling code in netpoll_send_skb_on_dev() has two problems. 1) It exits without unlocking the TXQ. 2) It then tries to queue a NULL skb to npinfo->txq. Reported-by: Ahmed Tamrawi <atamrawi@iastate.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: fix rx_hook() interface by passing the skbAntonio Quartulli2013-10-251-13/+18
| | | | | | | | | | | | | | | | | | Right now skb->data is passed to rx_hook() even if the skb has not been linearised and without giving rx_hook() a way to linearise it. Change the rx_hook() interface and make it accept the skb and the offset to the UDP payload as arguments. rx_hook() is also renamed to rx_skb_hook() to ensure that out of the tree users notice the API change. In this way any rx_skb_hook() implementation can perform all the needed operations to properly (and safely) access the skb data. Signed-off-by: Antonio Quartulli <antonio@meshcoding.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: fix NULL pointer dereference in netpoll_cleanupNikolay Aleksandrov2013-09-191-5/+4
| | | | | | | | | | | | | | | | | | | | I've been hitting a NULL ptr deref while using netconsole because the np->dev check and the pointer manipulation in netpoll_cleanup are done without rtnl and the following sequence happens when having a netconsole over a vlan and we remove the vlan while disabling the netconsole: CPU 1 CPU2 removes vlan and calls the notifier enters store_enabled(), calls netdev_cleanup which checks np->dev and then waits for rtnl executes the netconsole netdev release notifier making np->dev == NULL and releases rtnl continues to dereference a member of np->dev which at this point is == NULL Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>