wireguard-linux/drivers, branch jd/shorter-socket-lock

wireguard: socket: do not hold locks while transmitting packets

2020-05-05T00:04:01Z

Before, we followed this pattern for using the udp_tunnel api: rcu_read_lock_bh(); sock = rcu_dereference(obj->sock); ... udp_tunnel_xmit_skb(..., sock, ...); rcu_read_unlock_bh(); This commit changes that to use a reference counter instead: rcu_read_lock_bh(); sock = rcu_dereference(obj->sock); sock_hold(sock); rcu_read_unlock_bh(); ... udp_tunnel_xmit_skb(..., sock, ...); sock_put(sock); The advantage of the latter approach is that we now no longer hold any locks while udp_tunnel_xmit_skb runs, since it could be somewhat slow on systems with advanced qdisc or netfilter configurations. This should avoid potential RCU stalls in those situations. This commit makes sure we're holding neither the rcu read lock nor the endpoint read lock when udp_tunnel_xmit_skb is called. Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Signed-off-by: Jason A. Donenfeld

wireguard: send/receive: cond_resched() when processing worker ringbuffers

2020-05-05T00:03:51Z

Users with pathological hardware reported CPU stalls on CONFIG_ PREEMPT_VOLUNTARY=y, because the ringbuffers would stay full, meaning these workers would never terminate. That turned out not to be okay on systems without forced preemption, which Sultan observed. This commit adds a cond_resched() to the bottom of each loop iteration, so that these workers don't hog the core. Note that we don't need this on the napi poll worker, since that terminates after its budget is expended. Suggested-by: Sultan Alsawaf Reported-by: Wang Jian Signed-off-by: Jason A. Donenfeld

wireguard: socket: remove errant restriction on looping to self

2020-05-04T08:39:46Z

It's already possible to create two different interfaces and loop packets between them. This has always been possible with tunnels in the kernel, and isn't specific to wireguard. Therefore, the networking stack already needs to deal with that. At the very least, the packet winds up exceeding the MTU and is discarded at that point. So, since this is already something that happens, there's no need to forbid the not very exceptional case of routing a packet back to the same interface; this loop is no different than others, and we shouldn't special case it, but rather rely on generic handling of loops in general. This also makes it easier to do interesting things with wireguard such as onion routing. At the same time, we add a selftest for this, ensuring that both onion routing works and infinite routing loops do not crash the kernel. We also add a test case for wireguard interfaces nesting packets and sending traffic between each other, as well as the loop in this case too. We make sure to send some throughput-heavy traffic for this use case, to stress out any possible recursion issues with the locks around workqueues. Fixes: e7096c131e51 ("net: WireGuard secure network tunnel") Signed-off-by: Jason A. Donenfeld

gtp: set NLM_F_MULTI flag in gtp_genl_dump_pdp()

2020-05-01T22:34:09Z

In drivers/net/gtp.c, gtp_genl_dump_pdp() should set NLM_F_MULTI flag since it returns multipart message. This patch adds a new arg "flags" in gtp_genl_fill_info() so that flags can be set by the callers. Signed-off-by: Yoshiyuki Kurauchi Signed-off-by: David S. Miller

cxgb4: Add missing annotation for service_ofldq()

2020-05-01T22:31:37Z

Sparse reports a warning at service_ofldq() warning: context imbalance in service_ofldq() - unexpected unlock The root cause is the missing annotation at service_ofldq() Add the missing __must_hold(&q->sendq.lock) annotation Signed-off-by: Jules Irenge Signed-off-by: David S. Miller

net: Make PTP-specific drivers depend on PTP_1588_CLOCK

2020-05-01T22:27:51Z

Commit d1cbfd771ce8 ("ptp_clock: Allow for it to be optional") changed all PTP-capable Ethernet drivers from `select PTP_1588_CLOCK` to `imply PTP_1588_CLOCK`, "in order to break the hard dependency between the PTP clock subsystem and ethernet drivers capable of being clock providers." As a result it is possible to build PTP-capable Ethernet drivers without the PTP subsystem by deselecting PTP_1588_CLOCK. Drivers are required to handle the missing dependency gracefully. Some PTP-capable Ethernet drivers (e.g., TI_CPSW) factor their PTP code out into separate drivers (e.g., TI_CPTS_MOD). The above commit also changed these PTP-specific drivers to `imply PTP_1588_CLOCK`, making it possible to build them without the PTP subsystem. But as Grygorii Strashko noted in [1]: On Wed, Apr 22, 2020 at 02:16:11PM +0300, Grygorii Strashko wrote: > Another question is that CPTS completely nonfunctional in this case and > it was never expected that somebody will even try to use/run such > configuration (except for random build purposes). In my view, enabling a PTP-specific driver without the PTP subsystem is a configuration error made possible by the above commit. Kconfig should not allow users to create a configuration with missing dependencies that results in "completely nonfunctional" drivers. I audited all network drivers that call ptp_clock_register() but merely `imply PTP_1588_CLOCK` and found five PTP-specific drivers that are likely nonfunctional without PTP_1588_CLOCK: NET_DSA_MV88E6XXX_PTP NET_DSA_SJA1105_PTP MACB_USE_HWSTAMP CAVIUM_PTP TI_CPTS_MOD Note how these symbols all reference PTP or timestamping in their name; this is a clue that they depend on PTP_1588_CLOCK. Change them from `imply PTP_1588_CLOCK` [2] to `depends on PTP_1588_CLOCK`. I'm not using `select PTP_1588_CLOCK` here because PTP_1588_CLOCK has its own dependencies, which `select` would not transitively apply. Additionally, remove the `select NET_PTP_CLASSIFY` from CPTS_TI_MOD; PTP_1588_CLOCK already selects that. [1]: https://lore.kernel.org/lkml/c04458ed-29ee-1797-3a11-7f3f560553e6@ti.com/ [2]: NET_DSA_SJA1105_PTP had never declared any type of dependency on PTP_1588_CLOCK (`imply` or otherwise); adding a `depends on PTP_1588_CLOCK` here seems appropriate. Cc: Arnd Bergmann Cc: Richard Cochran Cc: Nicolas Pitre Cc: Grygorii Strashko Cc: Geert Uytterhoeven Fixes: d1cbfd771ce8 ("ptp_clock: Allow for it to be optional") Signed-off-by: Clay McClure Signed-off-by: David S. Miller

hv_netvsc: Fix netvsc_start_xmit's return type

2020-05-01T22:24:46Z

netvsc_start_xmit is used as a callback function for the ndo_start_xmit function pointer. ndo_start_xmit's return type is netdev_tx_t but netvsc_start_xmit's return type is int. This causes a failure with Control Flow Integrity (CFI), which requires function pointer prototypes and callback function definitions to match exactly. When CFI is in enforcing, the kernel panics. When booting a CFI kernel with WSL 2, the VM is immediately terminated because of this. The splat when CONFIG_CFI_PERMISSIVE is used: [ 5.916765] CFI failure (target: netvsc_start_xmit+0x0/0x10): [ 5.916771] WARNING: CPU: 8 PID: 0 at kernel/cfi.c:29 __cfi_check_fail+0x2e/0x40 [ 5.916772] Modules linked in: [ 5.916774] CPU: 8 PID: 0 Comm: swapper/8 Not tainted 5.7.0-rc3-next-20200424-microsoft-cbl-00001-ged4eb37d2c69-dirty #1 [ 5.916776] RIP: 0010:__cfi_check_fail+0x2e/0x40 [ 5.916777] Code: 48 c7 c7 70 98 63 a9 48 c7 c6 11 db 47 a9 e8 69 55 59 00 85 c0 75 02 5b c3 48 c7 c7 73 c6 43 a9 48 89 de 31 c0 e8 12 2d f0 ff <0f> 0b 5b c3 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 85 f6 74 25 [ 5.916778] RSP: 0018:ffffa803c0260b78 EFLAGS: 00010246 [ 5.916779] RAX: 712a1af25779e900 RBX: ffffffffa8cf7950 RCX: ffffffffa962cf08 [ 5.916779] RDX: ffffffffa9c36b60 RSI: 0000000000000082 RDI: ffffffffa9c36b5c [ 5.916780] RBP: ffff8ffc4779c2c0 R08: 0000000000000001 R09: ffffffffa9c3c300 [ 5.916781] R10: 0000000000000151 R11: ffffffffa9c36b60 R12: ffff8ffe39084000 [ 5.916782] R13: ffffffffa8cf7950 R14: ffffffffa8d12cb0 R15: ffff8ffe39320140 [ 5.916784] FS: 0000000000000000(0000) GS:ffff8ffe3bc00000(0000) knlGS:0000000000000000 [ 5.916785] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 5.916786] CR2: 00007ffef5749408 CR3: 00000002f4f5e000 CR4: 0000000000340ea0 [ 5.916787] Call Trace: [ 5.916788] [ 5.916790] __cfi_check+0x3ab58/0x450e0 [ 5.916793] ? dev_hard_start_xmit+0x11f/0x160 [ 5.916795] ? sch_direct_xmit+0xf2/0x230 [ 5.916796] ? __dev_queue_xmit.llvm.11471227737707190958+0x69d/0x8e0 [ 5.916797] ? neigh_resolve_output+0xdf/0x220 [ 5.916799] ? neigh_connected_output.cfi_jt+0x8/0x8 [ 5.916801] ? ip6_finish_output2+0x398/0x4c0 [ 5.916803] ? nf_nat_ipv6_out+0x10/0xa0 [ 5.916804] ? nf_hook_slow+0x84/0x100 [ 5.916807] ? ip6_input_finish+0x8/0x8 [ 5.916807] ? ip6_output+0x6f/0x110 [ 5.916808] ? __ip6_local_out.cfi_jt+0x8/0x8 [ 5.916810] ? mld_sendpack+0x28e/0x330 [ 5.916811] ? ip_rt_bug+0x8/0x8 [ 5.916813] ? mld_ifc_timer_expire+0x2db/0x400 [ 5.916814] ? neigh_proxy_process+0x8/0x8 [ 5.916816] ? call_timer_fn+0x3d/0xd0 [ 5.916817] ? __run_timers+0x2a9/0x300 [ 5.916819] ? rcu_core_si+0x8/0x8 [ 5.916820] ? run_timer_softirq+0x14/0x30 [ 5.916821] ? __do_softirq+0x154/0x262 [ 5.916822] ? native_x2apic_icr_write+0x8/0x8 [ 5.916824] ? irq_exit+0xba/0xc0 [ 5.916825] ? hv_stimer0_vector_handler+0x99/0xe0 [ 5.916826] ? hv_stimer0_callback_vector+0xf/0x20 [ 5.916826] [ 5.916828] ? hv_stimer_global_cleanup.cfi_jt+0x8/0x8 [ 5.916829] ? raw_setsockopt+0x8/0x8 [ 5.916830] ? default_idle+0xe/0x10 [ 5.916832] ? do_idle.llvm.10446269078108580492+0xb7/0x130 [ 5.916833] ? raw_setsockopt+0x8/0x8 [ 5.916833] ? cpu_startup_entry+0x15/0x20 [ 5.916835] ? cpu_hotplug_enable.cfi_jt+0x8/0x8 [ 5.916836] ? start_secondary+0x188/0x190 [ 5.916837] ? secondary_startup_64+0xa5/0xb0 [ 5.916838] ---[ end trace f2683fa869597ba5 ]--- Avoid this by using the right return type for netvsc_start_xmit. Fixes: fceaf24a943d8 ("Staging: hv: add the Hyper-V virtual network driver") Link: https://github.com/ClangBuiltLinux/linux/issues/1009 Signed-off-by: Nathan Chancellor Reviewed-by: Haiyang Zhang Signed-off-by: David S. Miller

net: phy: DP83TC811: Fix WoL in config init to be disabled

2020-05-01T22:23:44Z

The WoL feature should be disabled when config_init is called and the feature should turned on or off when set_wol is called. In addition updated the calls to modify the registers to use the set_bit and clear_bit function calls. Fixes: 6d749428788b ("net: phy: DP83TC811: Introduce support for the DP83TC811 phy") Signed-off-by: Dan Murphy Signed-off-by: David S. Miller

net: phy: DP83822: Fix WoL in config init to be disabled

2020-05-01T22:23:44Z

The WoL feature should be disabled when config_init is called and the feature should turned on or off when set_wol is called. In addition updated the calls to modify the registers to use the set_bit and clear_bit function calls. Fixes: 3b427751a9d0 ("net: phy: DP83822 initial driver submission") Signed-off-by: Dan Murphy Signed-off-by: David S. Miller

cxgb4: fix EOTID leak when disabling TC-MQPRIO offload

2020-05-01T04:01:46Z

Under heavy load, the EOTID termination FLOWC request fails to get enqueued to the end of the Tx ring due to lack of credits. This results in EOTID leak. When disabling TC-MQPRIO offload, the link is already brought down to cleanup EOTIDs. So, flush any pending enqueued skbs that can't be sent outside the wire, to make room for FLOWC request. Also, move the FLOWC descriptor consumption logic closer to when the FLOWC request is actually posted to hardware. Fixes: 0e395b3cb1fb ("cxgb4: add FLOWC based QoS offload") Signed-off-by: Rahul Lakkireddy Signed-off-by: David S. Miller