- 29 Jan, 2015 6 commits
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David S. Miller authored
Neal Cardwell says: ==================== fix stretch ACK bugs in TCP CUBIC and Reno This patch series fixes the TCP CUBIC and Reno congestion control modules to properly handle stretch ACKs in their respective additive increase modes, and in the transitions from slow start to additive increase. This finishes the project started by commit 9f9843a7 ("tcp: properly handle stretch acks in slow start"), which fixed behavior for TCP congestion control when handling stretch ACKs in slow start mode. Motivation: In the Jan 2015 netdev thread 'BW regression after "tcp: refine TSO autosizing"', Eyal Perry documented a regression that Eric Dumazet determined was caused by improper handling of TCP stretch ACKs. Background: LRO, GRO, delayed ACKs, and middleboxes can cause "stretch ACKs" that cover more than the RFC-specified maximum of 2 packets. These stretch ACKs can cause serious performance shortfalls in common congestion control algorithms, like Reno and CUBIC, which were designed and tuned years ago with receiver hosts that were not using LRO or GRO, and were instead ACKing every other packet. Testing: at Google we have been using this approach for handling stretch ACKs for CUBIC datacenter and Internet traffic for several years, with good results. v2: * fixed return type of tcp_slow_start() to be u32 instead of int ==================== Signed-off-by:
David S. Miller <davem@davemloft.net>
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Neal Cardwell authored
This patch fixes a bug in CUBIC that causes cwnd to increase slightly too slowly when multiple ACKs arrive in the same jiffy. If cwnd is supposed to increase at a rate of more than once per jiffy, then CUBIC was sometimes too slow. Because the bic_target is calculated for a future point in time, calculated with time in jiffies, the cwnd can increase over the course of the jiffy while the bic_target calculated as the proper CUBIC cwnd at time t=tcp_time_stamp+rtt does not increase, because tcp_time_stamp only increases on jiffy tick boundaries. So since the cnt is set to: ca->cnt = cwnd / (bic_target - cwnd); as cwnd increases but bic_target does not increase due to jiffy granularity, the cnt becomes too large, causing cwnd to increase too slowly. For example: - suppose at the beginning of a jiffy, cwnd=40, bic_target=44 - so CUBIC sets: ca->cnt = cwnd / (bic_target - cwnd) = 40 / (44 - 40) = 40/4 = 10 - suppose we get 10 acks, each for 1 segment, so tcp_cong_avoid_ai() increases cwnd to 41 - so CUBIC sets: ca->cnt = cwnd / (bic_target - cwnd) = 41 / (44 - 41) = 41 / 3 = 13 So now CUBIC will wait for 13 packets to be ACKed before increasing cwnd to 42, insted of 10 as it should. The fix is to avoid adjusting the slope (determined by ca->cnt) multiple times within a jiffy, and instead skip to compute the Reno cwnd, the "TCP friendliness" code path. Reported-by:
Eyal Perry <eyalpe@mellanox.com> Signed-off-by:
Neal Cardwell <ncardwell@google.com> Signed-off-by:
Yuchung Cheng <ycheng@google.com> Signed-off-by:
Eric Dumazet <edumazet@google.com> Signed-off-by:
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Neal Cardwell authored
Change CUBIC to properly handle stretch ACKs in additive increase mode by passing in the count of ACKed packets to tcp_cong_avoid_ai(). In addition, because we are now precisely accounting for stretch ACKs, including delayed ACKs, we can now remove the delayed ACK tracking and estimation code that tracked recent delayed ACK behavior in ca->delayed_ack. Reported-by:
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Neal Cardwell authored
Change Reno to properly handle stretch ACKs in additive increase mode by passing in the count of ACKed packets to tcp_cong_avoid_ai(). In addition, if snd_cwnd crosses snd_ssthresh during slow start processing, and we then exit slow start mode, we need to carry over any remaining "credit" for packets ACKed and apply that to additive increase by passing this remaining "acked" count to tcp_cong_avoid_ai(). Reported-by:
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Neal Cardwell authored
tcp_cong_avoid_ai() was too timid (snd_cwnd increased too slowly) on "stretch ACKs" -- cases where the receiver ACKed more than 1 packet in a single ACK. For example, suppose w is 10 and we get a stretch ACK for 20 packets, so acked is 20. We ought to increase snd_cwnd by 2 (since acked/w = 20/10 = 2), but instead we were only increasing cwnd by 1. This patch fixes that behavior. Reported-by:
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Neal Cardwell authored
LRO, GRO, delayed ACKs, and middleboxes can cause "stretch ACKs" that cover more than the RFC-specified maximum of 2 packets. These stretch ACKs can cause serious performance shortfalls in common congestion control algorithms that were designed and tuned years ago with receiver hosts that were not using LRO or GRO, and were instead politely ACKing every other packet. This patch series fixes Reno and CUBIC to handle stretch ACKs. This patch prepares for the upcoming stretch ACK bug fix patches. It adds an "acked" parameter to tcp_cong_avoid_ai() to allow for future fixes to tcp_cong_avoid_ai() to correctly handle stretch ACKs, and changes all congestion control algorithms to pass in 1 for the ACKed count. It also changes tcp_slow_start() to return the number of packet ACK "credits" that were not processed in slow start mode, and can be processed by the congestion control module in additive increase mode. In future patches we will fix tcp_cong_avoid_ai() to handle stretch ACKs, and fix Reno and CUBIC handling of stretch ACKs in slow start and additive increase mode. Reported-by:
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- 27 Jan, 2015 34 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds authored
Pull networking fixes from David Miller: 1) Don't OOPS on socket AIO, from Christoph Hellwig. 2) Scheduled scans should be aborted upon RFKILL, from Emmanuel Grumbach. 3) Fix sleep in atomic context in kvaser_usb, from Ahmed S Darwish. 4) Fix RCU locking across copy_to_user() in bpf code, from Alexei Starovoitov. 5) Lots of crash, memory leak, short TX packet et al bug fixes in sh_eth from Ben Hutchings. 6) Fix memory corruption in SCTP wrt. INIT collitions, from Daniel Borkmann. 7) Fix return value logic for poll handlers in netxen, enic, and bnx2x. From Eric Dumazet and Govindarajulu Varadarajan. 8) Header length calculation fix in mac80211 from Fred Chou. 9) mv643xx_eth doesn't handle highmem correctly in non-TSO code paths. From Ezequiel Garcia. 10) udp_diag has bogus logic in it's hash chain skipping, copy same fix tcp diag used. From Herbert Xu. 11) amd-xgbe programs wrong rx flow control register, from Thomas Lendacky. 12) Fix race leading to use after free in ping receive path, from Subash Abhinov Kasiviswanathan. 13) Cache redirect routes otherwise we can get a heavy backlog of rcu jobs liberating DST_NOCACHE entries. From Hannes Frederic Sowa. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (48 commits) net: don't OOPS on socket aio stmmac: prevent probe drivers to crash kernel bnx2x: fix napi poll return value for repoll ipv6: replacing a rt6_info needs to purge possible propagated rt6_infos too sh_eth: Fix DMA-API usage for RX buffers sh_eth: Check for DMA mapping errors on transmit sh_eth: Ensure DMA engines are stopped before freeing buffers sh_eth: Remove RX overflow log messages ping: Fix race in free in receive path udp_diag: Fix socket skipping within chain can: kvaser_usb: Fix state handling upon BUS_ERROR events can: kvaser_usb: Retry the first bulk transfer on -ETIMEDOUT can: kvaser_usb: Send correct context to URB completion can: kvaser_usb: Do not sleep in atomic context ipv4: try to cache dst_entries which would cause a redirect samples: bpf: relax test_maps check bpf: rcu lock must not be held when calling copy_to_user() net: sctp: fix slab corruption from use after free on INIT collisions net: mv643xx_eth: Fix highmem support in non-TSO egress path sh_eth: Fix serialisation of interrupt disable with interrupt & NAPI handlers ... -
Christoph Hellwig authored
Signed-off-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
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Andy Shevchenko authored
In the case when alloc_netdev fails we return NULL to a caller. But there is no check for NULL in the probe drivers. This patch changes NULL to an error pointer. The function description is amended to reflect what we may get returned. Signed-off-by:
Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by:
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git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linuxLinus Torvalds authored
Pull powerpc fixes from Michael Ellerman: "Two powerpc fixes" * tag 'powerpc-3.19-5' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: powerpc/powernv: Restore LPCR with LPCR_PECE1 cleared powerpc/xmon: Fix another endiannes issue in RTAS call from xmon
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git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linuxLinus Torvalds authored
Pull one more module fix from Rusty Russell: "SCSI was using module_refcount() to figure out when the module was unloading: this broke with new atomic refcounting. The code is still suspicious, but this solves the WARN_ON()" * tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: scsi: always increment reference count
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Govindarajulu Varadarajan authored
With the commit d75b1ade ("net: less interrupt masking in NAPI") napi repoll is done only when work_done == budget. When in busy_poll is we return 0 in napi_poll. We should return budget. Signed-off-by:
Govindarajulu Varadarajan <_govind@gmx.com> Acked-by:
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git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsecDavid S. Miller authored
Steffen Klassert says: ==================== ipsec 2015-01-26 Just two small fixes for _decode_session6() where we might decode to wrong header information in some rare situations. Please pull or let me know if there are problems. ==================== Signed-off-by: -
Hannes Frederic Sowa authored
Lubomir Rintel reported that during replacing a route the interface reference counter isn't correctly decremented. To quote bug <https://bugzilla.kernel.org/show_bug.cgi?id=91941>: | [root@rhel7-5 lkundrak]# sh -x lal | + ip link add dev0 type dummy | + ip link set dev0 up | + ip link add dev1 type dummy | + ip link set dev1 up | + ip addr add 2001:db8:8086::2/64 dev dev0 | + ip route add 2001:db8:8086::/48 dev dev0 proto static metric 20 | + ip route add 2001:db8:8088::/48 dev dev1 proto static metric 10 | + ip route replace 2001:db8:8086::/48 dev dev1 proto static metric 20 | + ip link del dev0 type dummy | Message from syslogd@rhel7-5 at Jan 23 10:54:41 ... | kernel:unregister_netdevice: waiting for dev0 to become free. Usage count = 2 | | Message from syslogd@rhel7-5 at Jan 23 10:54:51 ... | kernel:unregister_netdevice: waiting for dev0 to become free. Usage count = 2 During replacement of a rt6_info we must walk all parent nodes and check if the to be replaced rt6_info got propagated. If so, replace it with an alive one. Fixes: 4a287eba ("IPv6 routing, NLM_F_* flag support: REPLACE and EXCL flags support, warn about missing CREATE flag") Reported-by:
Lubomir Rintel <lkundrak@v3.sk> Signed-off-by:
Hannes Frederic Sowa <hannes@stressinduktion.org> Tested-by:
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David S. Miller authored
Ben Hutchings says: ==================== Fixes for sh_eth #3 I'm continuing review and testing of Ethernet support on the R-Car H2 chip. This series fixes the last of the more serious issues I've found. These are not tested on any of the other supported chips. ==================== Signed-off-by: -
Ben Hutchings authored
- Use the return value of dma_map_single(), rather than calling virt_to_page() separately - Check for mapping failue - Call dma_unmap_single() rather than dma_sync_single_for_cpu() Signed-off-by:
Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by:
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Ben Hutchings authored
dma_map_single() may fail if an IOMMU or swiotlb is in use, so we need to check for this. Signed-off-by:
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Ben Hutchings authored
Currently we try to clear EDRRR and EDTRR and immediately continue to free buffers. This is unsafe because: - In general, register writes are not serialised with DMA, so we still have to wait for DMA to complete somehow - The R8A7790 (R-Car H2) manual states that the TX running flag cannot be cleared by writing to EDTRR - The same manual states that clearing the RX running flag only stops RX DMA at the next packet boundary I applied this patch to the driver to detect DMA writes to freed buffers: > --- a/drivers/net/ethernet/renesas/sh_eth.c > +++ b/drivers/net/ethernet/renesas/sh_eth.c > @@ -1098,7 +1098,14 @@ static void sh_eth_ring_free(struct net_device *ndev) > /* Free Rx skb ringbuffer */ > if (mdp->rx_skbuff) { > for (i = 0; i < mdp->num_rx_ring; i++) > + memcpy(mdp->rx_skbuff[i]->data, > + "Hello, world", 12); > + msleep(100); > + for (i = 0; i < mdp->num_rx_ring; i++) { > + WARN_ON(memcmp(mdp->rx_skbuff[i]->data, > + "Hello, world", 12)); > dev_kfree_skb(mdp->rx_skbuff[i]); > + } > } > kfree(mdp->rx_skbuff); > mdp->rx_skbuff = NULL; then ran the loop: while ethtool -G eth0 rx 128 ; ethtool -G eth0 rx 64; do echo -n .; done and 'ping -f' toward the sh_eth port from another machine. The warning fired several times a minute. To fix these issues: - Deactivate all TX descriptors rather than writing to EDTRR - As there seems to be no way of telling when RX DMA is stopped, perform a soft reset to ensure that both DMA enginess are stopped - To reduce the possibility of the reset truncating a transmitted frame, disable egress and wait a reasonable time to reach a packet boundary before resetting - Update statistics before resetting (The 'reasonable time' does not allow for CS/CD in half-duplex mode, but half-duplex no longer seems reasonable!) Signed-off-by: -
Ben Hutchings authored
If RX traffic is overflowing the FIFO or DMA ring, logging every time this happens just makes things worse. These errors are visible in the statistics anyway. Signed-off-by:
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David S. Miller authored
Merge tag 'linux-can-fixes-for-3.19-20150127' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can Marc Kleine-Budde says: ==================== pull-request: can 2015-01-27 this is another pull request for net/master which consists of 4 patches. All 4 patches are contributed by Ahmed S. Darwish, he fixes more problems in the kvaser_usb driver. David, please merge net/master to net-next/master, as we have more kvaser_usb patches in the queue, that target net-next. ==================== Signed-off-by:
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subashab@codeaurora.org authored
An exception is seen in ICMP ping receive path where the skb destructor sock_rfree() tries to access a freed socket. This happens because ping_rcv() releases socket reference with sock_put() and this internally frees up the socket. Later icmp_rcv() will try to free the skb and as part of this, skb destructor is called and which leads to a kernel panic as the socket is freed already in ping_rcv(). -->|exception -007|sk_mem_uncharge -007|sock_rfree -008|skb_release_head_state -009|skb_release_all -009|__kfree_skb -010|kfree_skb -011|icmp_rcv -012|ip_local_deliver_finish Fix this incorrect free by cloning this skb and processing this cloned skb instead. This patch was suggested by Eric Dumazet Signed-off-by:
Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by:
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Herbert Xu authored
While working on rhashtable walking I noticed that the UDP diag dumping code is buggy. In particular, the socket skipping within a chain never happens, even though we record the number of sockets that should be skipped. As this code was supposedly copied from TCP, this patch does what TCP does and resets num before we walk a chain. Signed-off-by:
Herbert Xu <herbert@gondor.apana.org.au> Acked-by:
Pavel Emelyanov <xemul@parallels.com> Signed-off-by:
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Ahmed S. Darwish authored
While being in an ERROR_WARNING state, and receiving further bus error events with error counters still in the ERROR_WARNING range of 97-127 inclusive, the state handling code erroneously reverts back to ERROR_ACTIVE. Per the CAN standard, only revert to ERROR_ACTIVE when the error counters are less than 96. Moreover, in certain Kvaser models, the BUS_ERROR flag is always set along with undefined bits in the M16C status register. Thus use bitwise operators instead of full equality for checking that register against bus errors. Signed-off-by:
Ahmed S. Darwish <ahmed.darwish@valeo.com> Cc: linux-stable <stable@vger.kernel.org> Signed-off-by:
Marc Kleine-Budde <mkl@pengutronix.de>
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Ahmed S. Darwish authored
On some x86 laptops, plugging a Kvaser device again after an unplug makes the firmware always ignore the very first command. For such a case, provide some room for retries instead of completely exiting the driver init code. Signed-off-by:
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Ahmed S. Darwish authored
Send expected argument to the URB completion hander: a CAN netdevice instead of the network interface private context `kvaser_usb_net_priv'. This was discovered by having some garbage in the kernel log in place of the netdevice names: can0 and can1. Signed-off-by:
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Ahmed S. Darwish authored
Upon receiving a hardware event with the BUS_RESET flag set, the driver kills all of its anchored URBs and resets all of its transmit URB contexts. Unfortunately it does so under the context of URB completion handler `kvaser_usb_read_bulk_callback()', which is often called in an atomic context. While the device is flooded with many received error packets, usb_kill_urb() typically sleeps/reschedules till the transfer request of each killed URB in question completes, leading to the sleep in atomic bug. [3] In v2 submission of the original driver patch [1], it was stated that the URBs kill and tx contexts reset was needed since we don't receive any tx acknowledgments later and thus such resources will be locked down forever. Fortunately this is no longer needed since an earlier bugfix in this patch series is now applied: all tx URB contexts are reset upon CAN channel close. [2] Moreover, a BUS_RESET is now treated _exactly_ like a BUS_OFF event, which is the recommended handling method advised by the device manufacturer. [1] http://article.gmane.org/gmane.linux.network/239442 http://www.webcitation.org/6Vr2yagAQ [2] can: kvaser_usb: Reset all URB tx contexts upon channel close 889b77f7 [3] Stacktrace: <IRQ> [<ffffffff8158de87>] dump_stack+0x45/0x57 [<ffffffff8158b60c>] __schedule_bug+0x41/0x4f [<ffffffff815904b1>] __schedule+0x5f1/0x700 [<ffffffff8159360a>] ? _raw_spin_unlock_irqrestore+0xa/0x10 [<ffffffff81590684>] schedule+0x24/0x70 [<ffffffff8147d0a5>] usb_kill_urb+0x65/0xa0 [<ffffffff81077970>] ? prepare_to_wait_event+0x110/0x110 [<ffffffff8147d7d8>] usb_kill_anchored_urbs+0x48/0x80 [<ffffffffa01f4028>] kvaser_usb_unlink_tx_urbs+0x18/0x50 [kvaser_usb] [<ffffffffa01f45d0>] kvaser_usb_rx_error+0xc0/0x400 [kvaser_usb] [<ffffffff8108b14a>] ? vprintk_default+0x1a/0x20 [<ffffffffa01f5241>] kvaser_usb_read_bulk_callback+0x4c1/0x5f0 [kvaser_usb] [<ffffffff8147a73e>] __usb_hcd_giveback_urb+0x5e/0xc0 [<ffffffff8147a8a1>] usb_hcd_giveback_urb+0x41/0x110 [<ffffffffa0008748>] finish_urb+0x98/0x180 [ohci_hcd] [<ffffffff810cd1a7>] ? acct_account_cputime+0x17/0x20 [<ffffffff81069f65>] ? local_clock+0x15/0x30 [<ffffffffa000a36b>] ohci_work+0x1fb/0x5a0 [ohci_hcd] [<ffffffff814fbb31>] ? process_backlog+0xb1/0x130 [<ffffffffa000cd5b>] ohci_irq+0xeb/0x270 [ohci_hcd] [<ffffffff81479fc1>] usb_hcd_irq+0x21/0x30 [<ffffffff8108bfd3>] handle_irq_event_percpu+0x43/0x120 [<ffffffff8108c0ed>] handle_irq_event+0x3d/0x60 [<ffffffff8108ec84>] handle_fasteoi_irq+0x74/0x110 [<ffffffff81004dfd>] handle_irq+0x1d/0x30 [<ffffffff81004727>] do_IRQ+0x57/0x100 [<ffffffff8159482a>] common_interrupt+0x6a/0x6a Signed-off-by:
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David S. Miller authored
Merge tag 'mac80211-for-davem-2015-01-23' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211 Another set of last-minute fixes: * fix station double-removal when suspending while associating * fix the HT (802.11n) header length calculation * fix the CCK radiotap flag used for monitoring, a pretty old regression but a simple one-liner * fix per-station group-key handling Signed-off-by:
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Hannes Frederic Sowa authored
Not caching dst_entries which cause redirects could be exploited by hosts on the same subnet, causing a severe DoS attack. This effect aggravated since commit f8864972 ("ipv4: fix dst race in sk_dst_get()"). Lookups causing redirects will be allocated with DST_NOCACHE set which will force dst_release to free them via RCU. Unfortunately waiting for RCU grace period just takes too long, we can end up with >1M dst_entries waiting to be released and the system will run OOM. rcuos threads cannot catch up under high softirq load. Attaching the flag to emit a redirect later on to the specific skb allows us to cache those dst_entries thus reducing the pressure on allocation and deallocation. This issue was discovered by Marcelo Leitner. Cc: Julian Anastasov <ja@ssi.bg> Signed-off-by:
Marcelo Leitner <mleitner@redhat.com> Signed-off-by:
Florian Westphal <fw@strlen.de> Signed-off-by:
Julian Anastasov <ja@ssi.bg> Signed-off-by:
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David S. Miller authored
Alexei Starovoitov says: ==================== bpf: fix two bugs Michael Holzheu caught two issues (in bpf syscall and in the test). Fix them. Details in corresponding patches. ==================== Signed-off-by: -
Alexei Starovoitov authored
hash map is unordered, so get_next_key() iterator shouldn't rely on particular order of elements. So relax this test. Fixes: ffb65f27 ("bpf: add a testsuite for eBPF maps") Reported-by:
Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by:
Alexei Starovoitov <ast@plumgrid.com> Acked-by:
Daniel Borkmann <dborkman@redhat.com> Signed-off-by:
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Alexei Starovoitov authored
BUG: sleeping function called from invalid context at mm/memory.c:3732 in_atomic(): 0, irqs_disabled(): 0, pid: 671, name: test_maps 1 lock held by test_maps/671: #0: (rcu_read_lock){......}, at: [<0000000000264190>] map_lookup_elem+0xe8/0x260 Call Trace: ([<0000000000115b7e>] show_trace+0x12e/0x150) [<0000000000115c40>] show_stack+0xa0/0x100 [<00000000009b163c>] dump_stack+0x74/0xc8 [<000000000017424a>] ___might_sleep+0x23a/0x248 [<00000000002b58e8>] might_fault+0x70/0xe8 [<0000000000264230>] map_lookup_elem+0x188/0x260 [<0000000000264716>] SyS_bpf+0x20e/0x840 Fix it by allocating temporary buffer to store map element value. Fixes: db20fd2b ("bpf: add lookup/update/delete/iterate methods to BPF maps") Reported-by: -
Daniel Borkmann authored
When hitting an INIT collision case during the 4WHS with AUTH enabled, as already described in detail in commit 1be9a950 ("net: sctp: inherit auth_capable on INIT collisions"), it can happen that we occasionally still remotely trigger the following panic on server side which seems to have been uncovered after the fix from commit 1be9a950 ... [ 533.876389] BUG: unable to handle kernel paging request at 00000000ffffffff [ 533.913657] IP: [<ffffffff811ac385>] __kmalloc+0x95/0x230 [ 533.940559] PGD 5030f2067 PUD 0 [ 533.957104] Oops: 0000 [#1] SMP [ 533.974283] Modules linked in: sctp mlx4_en [...] [ 534.939704] Call Trace: [ 534.951833] [<ffffffff81294e30>] ? crypto_init_shash_ops+0x60/0xf0 [ 534.984213] [<ffffffff81294e30>] crypto_init_shash_ops+0x60/0xf0 [ 535.015025] [<ffffffff8128c8ed>] __crypto_alloc_tfm+0x6d/0x170 [ 535.045661] [<ffffffff8128d12c>] crypto_alloc_base+0x4c/0xb0 [ 535.074593] [<ffffffff8160bd42>] ? _raw_spin_lock_bh+0x12/0x50 [ 535.105239] [<ffffffffa0418c11>] sctp_inet_listen+0x161/0x1e0 [sctp] [ 535.138606] [<ffffffff814e43bd>] SyS_listen+0x9d/0xb0 [ 535.166848] [<ffffffff816149a9>] system_call_fastpath+0x16/0x1b ... or depending on the the application, for example this one: [ 1370.026490] BUG: unable to handle kernel paging request at 00000000ffffffff [ 1370.026506] IP: [<ffffffff811ab455>] kmem_cache_alloc+0x75/0x1d0 [ 1370.054568] PGD 633c94067 PUD 0 [ 1370.070446] Oops: 0000 [#1] SMP [ 1370.085010] Modules linked in: sctp kvm_amd kvm [...] [ 1370.963431] Call Trace: [ 1370.974632] [<ffffffff8120f7cf>] ? SyS_epoll_ctl+0x53f/0x960 [ 1371.000863] [<ffffffff8120f7cf>] SyS_epoll_ctl+0x53f/0x960 [ 1371.027154] [<ffffffff812100d3>] ? anon_inode_getfile+0xd3/0x170 [ 1371.054679] [<ffffffff811e3d67>] ? __alloc_fd+0xa7/0x130 [ 1371.080183] [<ffffffff816149a9>] system_call_fastpath+0x16/0x1b With slab debugging enabled, we can see that the poison has been overwritten: [ 669.826368] BUG kmalloc-128 (Tainted: G W ): Poison overwritten [ 669.826385] INFO: 0xffff880228b32e50-0xffff880228b32e50. First byte 0x6a instead of 0x6b [ 669.826414] INFO: Allocated in sctp_auth_create_key+0x23/0x50 [sctp] age=3 cpu=0 pid=18494 [ 669.826424] __slab_alloc+0x4bf/0x566 [ 669.826433] __kmalloc+0x280/0x310 [ 669.826453] sctp_auth_create_key+0x23/0x50 [sctp] [ 669.826471] sctp_auth_asoc_create_secret+0xcb/0x1e0 [sctp] [ 669.826488] sctp_auth_asoc_init_active_key+0x68/0xa0 [sctp] [ 669.826505] sctp_do_sm+0x29d/0x17c0 [sctp] [...] [ 669.826629] INFO: Freed in kzfree+0x31/0x40 age=1 cpu=0 pid=18494 [ 669.826635] __slab_free+0x39/0x2a8 [ 669.826643] kfree+0x1d6/0x230 [ 669.826650] kzfree+0x31/0x40 [ 669.826666] sctp_auth_key_put+0x19/0x20 [sctp] [ 669.826681] sctp_assoc_update+0x1ee/0x2d0 [sctp] [ 669.826695] sctp_do_sm+0x674/0x17c0 [sctp] Since this only triggers in some collision-cases with AUTH, the problem at heart is that sctp_auth_key_put() on asoc->asoc_shared_key is called twice when having refcnt 1, once directly in sctp_assoc_update() and yet again from within sctp_auth_asoc_init_active_key() via sctp_assoc_update() on the already kzfree'd memory, which is also consistent with the observation of the poison decrease from 0x6b to 0x6a (note: the overwrite is detected at a later point in time when poison is checked on new allocation). Reference counting of auth keys revisited: Shared keys for AUTH chunks are being stored in endpoints and associations in endpoint_shared_keys list. On endpoint creation, a null key is being added; on association creation, all endpoint shared keys are being cached and thus cloned over to the association. struct sctp_shared_key only holds a pointer to the actual key bytes, that is, struct sctp_auth_bytes which keeps track of users internally through refcounting. Naturally, on assoc or enpoint destruction, sctp_shared_key are being destroyed directly and the reference on sctp_auth_bytes dropped. User space can add keys to either list via setsockopt(2) through struct sctp_authkey and by passing that to sctp_auth_set_key() which replaces or adds a new auth key. There, sctp_auth_create_key() creates a new sctp_auth_bytes with refcount 1 and in case of replacement drops the reference on the old sctp_auth_bytes. A key can be set active from user space through setsockopt() on the id via sctp_auth_set_active_key(), which iterates through either endpoint_shared_keys and in case of an assoc, invokes (one of various places) sctp_auth_asoc_init_active_key(). sctp_auth_asoc_init_active_key() computes the actual secret from local's and peer's random, hmac and shared key parameters and returns a new key directly as sctp_auth_bytes, that is asoc->asoc_shared_key, plus drops the reference if there was a previous one. The secret, which where we eventually double drop the ref comes from sctp_auth_asoc_set_secret() with intitial refcount of 1, which also stays unchanged eventually in sctp_assoc_update(). This key is later being used for crypto layer to set the key for the hash in crypto_hash_setkey() from sctp_auth_calculate_hmac(). To close the loop: asoc->asoc_shared_key is freshly allocated secret material and independant of the sctp_shared_key management keeping track of only shared keys in endpoints and assocs. Hence, also commit 4184b2a7 ("net: sctp: fix memory leak in auth key management") is independant of this bug here since it concerns a different layer (though same structures being used eventually). asoc->asoc_shared_key is reference dropped correctly on assoc destruction in sctp_association_free() and when active keys are being replaced in sctp_auth_asoc_init_active_key(), it always has a refcount of 1. Hence, it's freed prematurely in sctp_assoc_update(). Simple fix is to remove that sctp_auth_key_put() from there which fixes these panics. Fixes: 730fc3d0 ("[SCTP]: Implete SCTP-AUTH parameter processing") Signed-off-by:
Vlad Yasevich <vyasevich@gmail.com> Acked-by:
Neil Horman <nhorman@tuxdriver.com> Signed-off-by:
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Linus Torvalds authored
Merge misc fixes from Andrew Morton: "Six fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: drivers/rtc/rtc-s5m.c: terminate s5m_rtc_id array with empty element printk: add dummy routine for when CONFIG_PRINTK=n mm/vmscan: fix highidx argument type memcg: remove extra newlines from memcg oom kill log x86, build: replace Perl script with Shell script mm: page_alloc: embed OOM killing naturally into allocation slowpath
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Ezequiel Garcia authored
Commit 69ad0dd7 Author: Ezequiel Garcia <ezequiel.garcia@free-electrons.com> Date: Mon May 19 13:59:59 2014 -0300 net: mv643xx_eth: Use dma_map_single() to map the skb fragments caused a nasty regression by removing the support for highmem skb fragments. By using page_address() to get the address of a fragment's page, we are assuming a lowmem page. However, such assumption is incorrect, as fragments can be in highmem pages, resulting in very nasty issues. This commit fixes this by using the skb_frag_dma_map() helper, which takes care of mapping the skb fragment properly. Additionally, the type of mapping is now tracked, so it can be unmapped using dma_unmap_page or dma_unmap_single when appropriate. This commit also fixes the error path in txq_init() to release the resources properly. Fixes: 69ad0dd7 ("net: mv643xx_eth: Use dma_map_single() to map the skb fragments") Reported-by:
Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by:
Ezequiel Garcia <ezequiel.garcia@free-electrons.com> Signed-off-by:
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David S. Miller authored
Ben Hutchings says: ==================== Fixes for sh_eth #2 I'm continuing review and testing of Ethernet support on the R-Car H2 chip. This series fixes more of the issues I've found, but it won't be the last set. These are not tested on any of the other supported chips. ==================== Signed-off-by: -
Ben Hutchings authored
In order to stop the RX path accessing the RX ring while it's being stopped or resized, we clear the interrupt mask (EESIPR) and then call free_irq() or synchronise_irq(). This is insufficient because the interrupt handler or NAPI poller may set EESIPR again after we clear it. Also, in sh_eth_set_ringparam() we currently don't disable NAPI polling at all. I could easily trigger a crash by running the loop: while ethtool -G eth0 rx 128 && ethtool -G eth0 rx 64; do echo -n .; done and 'ping -f' toward the sh_eth port from another machine. To fix this: - Add a software flag (irq_enabled) to signal whether interrupts should be enabled - In the interrupt handler, if the flag is clear then clear EESIPR and return - In the NAPI poller, if the flag is clear then don't set EESIPR - Set the flag before enabling interrupts in sh_eth_dev_init() and sh_eth_set_ringparam() - Clear the flag and serialise with the interrupt and NAPI handlers before clearing EESIPR in sh_eth_close() and sh_eth_set_ringparam() After this, I could run the loop for 100,000 iterations successfully. Signed-off-by:
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Ben Hutchings authored
If the device is down then no packet buffers should be allocated. We also must not touch its registers as it may be powered off. Signed-off-by:
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Ben Hutchings authored
We must only ever stop TX queues when they are full or the net device is not 'ready' so far as the net core, and specifically the watchdog, is concerned. Otherwise, the watchdog may fire *immediately* if no packets have been added to the queue in the last 5 seconds. What's more, sh_eth_tx_timeout() will likely crash if called while we're resizing the TX ring. I could easily trigger this by running the loop: while ethtool -G eth0 rx 128 && ethtool -G eth0 rx 64; do echo -n .; done Signed-off-by:
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Ben Hutchings authored
If an skb to be transmitted is shorter than the minimum Ethernet frame length, we currently set the DMA descriptor length to the minimum but do not add zero-padding. This could result in leaking sensitive data. We also pass different lengths to dma_map_single() and dma_unmap_single(). Use skb_padto() to pad properly, before calling dma_map_single(). Signed-off-by:
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Mugunthan V N authored
In Dual EMAC, the default VLANs are used to segregate Rx packets between the ports, so adding the same default VLAN to the switch will affect the normal packet transfers. So returning error on addition of dual EMAC default VLANs. Even if EMAC 0 default port VLAN is added to EMAC 1, it will lead to break dual EMAC port separations. Fixes: d9ba8f9e (driver: net: ethernet: cpsw: dual emac interface implementation) Cc: <stable@vger.kernel.org> # v3.9+ Reported-by:
Felipe Balbi <balbi@ti.com> Signed-off-by:
Mugunthan V N <mugunthanvnm@ti.com> Signed-off-by:
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