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* nfp: fix kdoc warnings on nested structuresJakub Kicinski2018-02-065-49/+55
| | | | | | | | | | | | | Commit 84ce5b987783 ("scripts: kernel-doc: improve nested logic to handle multiple identifiers") improved the handling of nested structure definitions in scripts/kernel-doc, and changed the expected format of documentation. This causes new warnings to appear on W=1 builds. Only comment changes. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge branch 'net-erspan-fixes'David S. Miller2018-02-065-61/+39Star
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | William Tu says: ==================== net: erspan fixes The first patch fixes erspan metadata extraction issue from packet header due to commit d350a823020e ("net: erspan: create erspan metadata uapi header"). The commit moves the erspan 'version' in 'struct erspan_metadata' in front of 'struct erspan_md2' for later extensibility, but breaks the existing metadata extraction code due to extra 4-byte size 'version'. The second patch fixes the case where tunnel device receives an erspan packet with different tunnel metadata (ex: version, index, hwid, direction), existing code overwrites the tunnel device's erspan configuration. The third patch fixes the bpf tests due to the above patches. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| * sample/bpf: fix erspan metadataWilliam Tu2018-02-062-27/+18Star
| | | | | | | | | | | | | | | | | | | | | | | | | | The commit c69de58ba84f ("net: erspan: use bitfield instead of mask and offset") changes the erspan header to use bitfield, and commit d350a823020e ("net: erspan: create erspan metadata uapi header") creates a uapi header file. The above two commit breaks the current erspan test. This patch fixes it by adapting the above two changes. Fixes: ac80c2a165af ("samples/bpf: add erspan v2 sample code") Fixes: ef88f89c830f ("samples/bpf: extend test_tunnel_bpf.sh with ERSPAN") Signed-off-by: William Tu <u9012063@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: erspan: fix erspan config overwriteWilliam Tu2018-02-062-18/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | When an erspan tunnel device receives an erpsan packet with different tunnel metadata (ex: version, index, hwid, direction), existing code overwrites the tunnel device's erspan configuration with the received packet's metadata. The patch fixes it. Fixes: 1a66a836da63 ("gre: add collect_md mode to ERSPAN tunnel") Fixes: f551c91de262 ("net: erspan: introduce erspan v2 for ip_gre") Fixes: ef7baf5e083c ("ip6_gre: add ip6 erspan collect_md mode") Fixes: 94d7d8f29287 ("ip6_gre: add erspan v2 support") Signed-off-by: William Tu <u9012063@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: erspan: fix metadata extractionWilliam Tu2018-02-063-16/+21
|/ | | | | | | | | | | | | | | Commit d350a823020e ("net: erspan: create erspan metadata uapi header") moves the erspan 'version' in front of the 'struct erspan_md2' for later extensibility reason. This breaks the existing erspan metadata extraction code because the erspan_md2 then has a 4-byte offset to between the erspan_metadata and erspan_base_hdr. This patch fixes it. Fixes: 1a66a836da63 ("gre: add collect_md mode to ERSPAN tunnel") Fixes: ef7baf5e083c ("ip6_gre: add ip6 erspan collect_md mode") Fixes: 1d7e2ed22f8d ("net: erspan: refactor existing erspan code") Signed-off-by: William Tu <u9012063@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* cls_u32: fix use after free in u32_destroy_key()Paolo Abeni2018-02-061-10/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Li Shuang reported an Oops with cls_u32 due to an use-after-free in u32_destroy_key(). The use-after-free can be triggered with: dev=lo tc qdisc add dev $dev root handle 1: htb default 10 tc filter add dev $dev parent 1: prio 5 handle 1: protocol ip u32 divisor 256 tc filter add dev $dev protocol ip parent 1: prio 5 u32 ht 800:: match ip dst\ 10.0.0.0/8 hashkey mask 0x0000ff00 at 16 link 1: tc qdisc del dev $dev root Which causes the following kasan splat: ================================================================== BUG: KASAN: use-after-free in u32_destroy_key.constprop.21+0x117/0x140 [cls_u32] Read of size 4 at addr ffff881b83dae618 by task kworker/u48:5/571 CPU: 17 PID: 571 Comm: kworker/u48:5 Not tainted 4.15.0+ #87 Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.1.7 06/16/2016 Workqueue: tc_filter_workqueue u32_delete_key_freepf_work [cls_u32] Call Trace: dump_stack+0xd6/0x182 ? dma_virt_map_sg+0x22e/0x22e print_address_description+0x73/0x290 kasan_report+0x277/0x360 ? u32_destroy_key.constprop.21+0x117/0x140 [cls_u32] u32_destroy_key.constprop.21+0x117/0x140 [cls_u32] u32_delete_key_freepf_work+0x1c/0x30 [cls_u32] process_one_work+0xae0/0x1c80 ? sched_clock+0x5/0x10 ? pwq_dec_nr_in_flight+0x3c0/0x3c0 ? _raw_spin_unlock_irq+0x29/0x40 ? trace_hardirqs_on_caller+0x381/0x570 ? _raw_spin_unlock_irq+0x29/0x40 ? finish_task_switch+0x1e5/0x760 ? finish_task_switch+0x208/0x760 ? preempt_notifier_dec+0x20/0x20 ? __schedule+0x839/0x1ee0 ? check_noncircular+0x20/0x20 ? firmware_map_remove+0x73/0x73 ? find_held_lock+0x39/0x1c0 ? worker_thread+0x434/0x1820 ? lock_contended+0xee0/0xee0 ? lock_release+0x1100/0x1100 ? init_rescuer.part.16+0x150/0x150 ? retint_kernel+0x10/0x10 worker_thread+0x216/0x1820 ? process_one_work+0x1c80/0x1c80 ? lock_acquire+0x1a5/0x540 ? lock_downgrade+0x6b0/0x6b0 ? sched_clock+0x5/0x10 ? lock_release+0x1100/0x1100 ? compat_start_thread+0x80/0x80 ? do_raw_spin_trylock+0x190/0x190 ? _raw_spin_unlock_irq+0x29/0x40 ? trace_hardirqs_on_caller+0x381/0x570 ? _raw_spin_unlock_irq+0x29/0x40 ? finish_task_switch+0x1e5/0x760 ? finish_task_switch+0x208/0x760 ? preempt_notifier_dec+0x20/0x20 ? __schedule+0x839/0x1ee0 ? kmem_cache_alloc_trace+0x143/0x320 ? firmware_map_remove+0x73/0x73 ? sched_clock+0x5/0x10 ? sched_clock_cpu+0x18/0x170 ? find_held_lock+0x39/0x1c0 ? schedule+0xf3/0x3b0 ? lock_downgrade+0x6b0/0x6b0 ? __schedule+0x1ee0/0x1ee0 ? do_wait_intr_irq+0x340/0x340 ? do_raw_spin_trylock+0x190/0x190 ? _raw_spin_unlock_irqrestore+0x32/0x60 ? process_one_work+0x1c80/0x1c80 ? process_one_work+0x1c80/0x1c80 kthread+0x312/0x3d0 ? kthread_create_worker_on_cpu+0xc0/0xc0 ret_from_fork+0x3a/0x50 Allocated by task 1688: kasan_kmalloc+0xa0/0xd0 __kmalloc+0x162/0x380 u32_change+0x1220/0x3c9e [cls_u32] tc_ctl_tfilter+0x1ba6/0x2f80 rtnetlink_rcv_msg+0x4f0/0x9d0 netlink_rcv_skb+0x124/0x320 netlink_unicast+0x430/0x600 netlink_sendmsg+0x8fa/0xd60 sock_sendmsg+0xb1/0xe0 ___sys_sendmsg+0x678/0x980 __sys_sendmsg+0xc4/0x210 do_syscall_64+0x232/0x7f0 return_from_SYSCALL_64+0x0/0x75 Freed by task 112: kasan_slab_free+0x71/0xc0 kfree+0x114/0x320 rcu_process_callbacks+0xc3f/0x1600 __do_softirq+0x2bf/0xc06 The buggy address belongs to the object at ffff881b83dae600 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 24 bytes inside of 4096-byte region [ffff881b83dae600, ffff881b83daf600) The buggy address belongs to the page: page:ffffea006e0f6a00 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 flags: 0x17ffffc0008100(slab|head) raw: 0017ffffc0008100 0000000000000000 0000000000000000 0000000100070007 raw: dead000000000100 dead000000000200 ffff880187c0e600 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff881b83dae500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff881b83dae580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff881b83dae600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff881b83dae680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff881b83dae700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== The problem is that the htnode is freed before the linked knodes and the latter will try to access the first at u32_destroy_key() time. This change addresses the issue using the htnode refcnt to guarantee the correct free order. While at it also add a RCU annotation, to keep sparse happy. v1 -> v2: use rtnl_derefence() instead of RCU read locks v2 -> v3: - don't check refcnt in u32_destroy_hnode() - cleaned-up u32_destroy() implementation - cleaned-up code comment v3 -> v4: - dropped unneeded comment Reported-by: Li Shuang <shuali@redhat.com> Fixes: c0d378ef1266 ("net_sched: use tcf_queue_work() in u32 filter") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: amd-xgbe: fix comparison to bitshift when dealing with a maskWolfram Sang2018-02-061-1/+1
| | | | | | | | | Due to a typo, the mask was destroyed by a comparison instead of a bit shift. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: phy: Handle not having GPIO enabled in the kernelAndrew Lunn2018-02-061-1/+2
| | | | | | | | | | | | | If CONFIG_GPIOLIB is disabled, fwnode_get_named_gpiod() becomes a stub function, which return -ENOSYS. Handle this in the same way as -ENOENT, i.e. assume there is no GPIO used to reset the PHYs. Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de> Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Fixes: bafbdd527d56 ("phylib: Add device reset GPIO support") Signed-off-by: David S. Miller <davem@davemloft.net>
* ibmvnic: fix empty firmware version and errors cleanupDesnes Augusto Nunes do Rosario2018-02-061-10/+4Star
| | | | | | | | | | This patch makes sure that the firmware version is never NULL. Moreover, it also performs some cleanup on the error messages. Fixes: a107311d7fdf ("ibmvnic: fix firmware version when no firmware level has been provided by the VIOS server") Signed-off-by: Desnes A. Nunes do Rosario <desnesn@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sctp: fix dst refcnt leak in sctp_v4_get_dstTommi Rantala2018-02-061-6/+4Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix dst reference count leak in sctp_v4_get_dst() introduced in commit 410f03831 ("sctp: add routing output fallback"): When walking the address_list, successive ip_route_output_key() calls may return the same rt->dst with the reference incremented on each call. The code would not decrement the dst refcount when the dst pointer was identical from the previous iteration, causing the dst refcnt leak. Testcase: ip netns add TEST ip netns exec TEST ip link set lo up ip link add dummy0 type dummy ip link add dummy1 type dummy ip link add dummy2 type dummy ip link set dev dummy0 netns TEST ip link set dev dummy1 netns TEST ip link set dev dummy2 netns TEST ip netns exec TEST ip addr add 192.168.1.1/24 dev dummy0 ip netns exec TEST ip link set dummy0 up ip netns exec TEST ip addr add 192.168.1.2/24 dev dummy1 ip netns exec TEST ip link set dummy1 up ip netns exec TEST ip addr add 192.168.1.3/24 dev dummy2 ip netns exec TEST ip link set dummy2 up ip netns exec TEST sctp_test -H 192.168.1.2 -P 20002 -h 192.168.1.1 -p 20000 -s -B 192.168.1.3 ip netns del TEST In 4.4 and 4.9 kernels this results to: [ 354.179591] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 364.419674] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 374.663664] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 384.903717] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 395.143724] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 405.383645] unregister_netdevice: waiting for lo to become free. Usage count = 1 ... Fixes: 410f03831 ("sctp: add routing output fallback") Fixes: 0ca50d12f ("sctp: fix src address selection if using secondary addresses") Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sctp: fix dst refcnt leak in sctp_v6_get_dst()Alexey Kodanev2018-02-061-3/+7
| | | | | | | | | | | | | | | | | | When going through the bind address list in sctp_v6_get_dst() and the previously found address is better ('matchlen > bmatchlen'), the code continues to the next iteration without releasing currently held destination. Fix it by releasing 'bdst' before continue to the next iteration, and instead of introducing one more '!IS_ERR(bdst)' check for dst_release(), move the already existed one right after ip6_dst_lookup_flow(), i.e. we shouldn't proceed further if we get an error for the route lookup. Fixes: dbc2b5e9a09e ("sctp: fix src address selection if using secondary addresses for ipv6") Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* dwc-xlgmac: remove Jie Deng as co-maintainerJie Deng2018-02-051-1/+0Star
| | | | | | | | Jose Abreu is working on this driver and I will leave Synopsys soon. Thus it does not seem appropriate for me to be a co-maintainer anymore. Signed-off-by: Jie Deng <jiedeng@synopsys.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* doc: Change the min default value of tcp_wmem/tcp_rmem.Tonghao Zhang2018-02-051-2/+2
| | | | | | | | | | The SK_MEM_QUANTUM was changed from PAGE_SIZE to 4096. And the tcp_wmem/tcp_rmem min default values are 4096. Fixes: bd68a2a854ad ("net: set SK_MEM_QUANTUM to 4096") Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller2018-02-0428-141/+1716
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Alexei Starovoitov says: ==================== pull-request: bpf 2018-02-02 The following pull-request contains BPF updates for your *net* tree. The main changes are: 1) support XDP attach in libbpf, from Eric. 2) minor fixes, from Daniel, Jakub, Yonghong, Alexei. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| * Merge branch 'libbpf-xdp-support'Alexei Starovoitov2018-02-0320-128/+1632
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Eric Leblond says: ==================== Here is an updated v8 version: - add if_link.h in uapi and remove the definition - fix a commit message - remove uapi from a include ==================== Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| | * samples/bpf: use bpf_set_link_xdp_fdEric Leblond2018-02-039-126/+24Star
| | | | | | | | | | | | | | | | | | | | | | | | Use bpf_set_link_xdp_fd instead of set_link_xdp_fd to remove some code duplication and benefit of netlink ext ack errors message. Signed-off-by: Eric Leblond <eric@regit.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| | * libbpf: add missing SPDX-License-IdentifierEric Leblond2018-02-034-0/+8
| | | | | | | | | | | | | | | | | | Signed-off-by: Eric Leblond <eric@regit.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| | * libbpf: add error reporting in XDPEric Leblond2018-02-035-2/+272
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Parse netlink ext attribute to get the error message returned by the card. Code is partially take from libnl. We add netlink.h to the uapi include of tools. And we need to avoid include of userspace netlink header to have a successful build of sample so nlattr.h has a define to avoid the inclusion. Using a direct define could have been an issue as NLMSGERR_ATTR_MAX can change in the future. We also define SOL_NETLINK if not defined to avoid to have to copy socket.h for a fixed value. Signed-off-by: Eric Leblond <eric@regit.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| | * libbpf: add function to setup XDPEric Leblond2018-02-033-0/+128
| | | | | | | | | | | | | | | | | | | | | | | | | | | Most of the code is taken from set_link_xdp_fd() in bpf_load.c and slightly modified to be library compliant. Signed-off-by: Eric Leblond <eric@regit.org> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| | * tools: add netlink.h and if_link.h in tools uapiEric Leblond2018-02-033-0/+1200
| |/ | | | | | | | | | | | | | | The headers are necessary for libbpf compilation on system with older version of the headers. Signed-off-by: Eric Leblond <eric@regit.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * bpf: fix bpf_prog_array_copy_to_user() issuesAlexei Starovoitov2018-02-031-8/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1. move copy_to_user out of rcu section to fix the following issue: ./include/linux/rcupdate.h:302 Illegal context switch in RCU read-side critical section! stack backtrace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 lockdep_rcu_suspicious+0x123/0x170 kernel/locking/lockdep.c:4592 rcu_preempt_sleep_check include/linux/rcupdate.h:301 [inline] ___might_sleep+0x385/0x470 kernel/sched/core.c:6079 __might_sleep+0x95/0x190 kernel/sched/core.c:6067 __might_fault+0xab/0x1d0 mm/memory.c:4532 _copy_to_user+0x2c/0xc0 lib/usercopy.c:25 copy_to_user include/linux/uaccess.h:155 [inline] bpf_prog_array_copy_to_user+0x217/0x4d0 kernel/bpf/core.c:1587 bpf_prog_array_copy_info+0x17b/0x1c0 kernel/bpf/core.c:1685 perf_event_query_prog_array+0x196/0x280 kernel/trace/bpf_trace.c:877 _perf_ioctl kernel/events/core.c:4737 [inline] perf_ioctl+0x3e1/0x1480 kernel/events/core.c:4757 2. move *prog under rcu, since it's not ok to dereference it afterwards 3. in a rare case of prog array being swapped between bpf_prog_array_length() and bpf_prog_array_copy_to_user() calls make sure to copy zeros to user space, so the user doesn't walk over uninited prog_ids while kernel reported uattr->query.prog_cnt > 0 Reported-by: syzbot+7dbcd2d3b85f9b608b23@syzkaller.appspotmail.com Fixes: 468e2f64d220 ("bpf: introduce BPF_PROG_QUERY command") Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * bpf: add documentation to compare clang "-target bpf" and default targetYonghong Song2018-02-021-0/+31
| | | | | | | | | | | | | | | | | | The added documentation explains how generated codes may differ between clang bpf target and default target, and when to use each target. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * bpf: fix null pointer deref in bpf_prog_test_run_xdpDaniel Borkmann2018-02-013-0/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | syzkaller was able to generate the following XDP program ... (18) r0 = 0x0 (61) r5 = *(u32 *)(r1 +12) (04) (u32) r0 += (u32) 0 (95) exit ... and trigger a NULL pointer dereference in ___bpf_prog_run() via bpf_prog_test_run_xdp() where this was attempted to run. Reason is that recent xdp_rxq_info addition to XDP programs updated all drivers, but not bpf_prog_test_run_xdp(), where xdp_buff is set up. Thus when context rewriter does the deref on the netdev it's NULL at runtime. Fix it by using xdp_rxq from loopback dev. __netif_get_rx_queue() helper can also be reused in various other locations later on. Fixes: 02dd3291b2f0 ("bpf: finally expose xdp_rxq_info to XDP bpf-programs") Reported-by: syzbot+1eb094057b338eb1fc00@syzkaller.appspotmail.com Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| * tools/bpf: permit selftests/bpf to be built in a different directoryYonghong Song2018-02-012-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix a couple of issues at tools/testing/selftests/bpf/Makefile so the following command make -C tools/testing/selftests/bpf OUTPUT=/home/yhs/tmp can put the built results into a different directory. Also add the built binary test_tcpbpf_user in the .gitignore file. Fixes: 6882804c916b ("selftests/bpf: add a test for overlapping packet range checks") Fixes: 9d1f15941967 ("bpf: move cgroup_helpers from samples/bpf/ to tools/testing/selftesting/bpf/") Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| * netdevsim: fix overflow on the error pathJakub Kicinski2018-02-011-3/+2Star
| | | | | | | | | | | | | | | | | | | | | | | | Undo loop condition on the error path would cause the i counter to go below zero, if allocation failure happened with the first (i.e. 0th) element of the array. Fixes: 395cacb5f1a0 ("netdevsim: bpf: support fake map offload") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
* | Merge branch 'x86-pti-for-linus' of ↵Linus Torvalds2018-02-0438-554/+977
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull spectre/meltdown updates from Thomas Gleixner: "The next round of updates related to melted spectrum: - The initial set of spectre V1 mitigations: - Array index speculation blocker and its usage for syscall, fdtable and the n180211 driver. - Speculation barrier and its usage in user access functions - Make indirect calls in KVM speculation safe - Blacklisting of known to be broken microcodes so IPBP/IBSR are not touched. - The initial IBPB support and its usage in context switch - The exposure of the new speculation MSRs to KVM guests. - A fix for a regression in x86/32 related to the cpu entry area - Proper whitelisting for known to be safe CPUs from the mitigations. - objtool fixes to deal proper with retpolines and alternatives - Exclude __init functions from retpolines which speeds up the boot process. - Removal of the syscall64 fast path and related cleanups and simplifications - Removal of the unpatched paravirt mode which is yet another source of indirect unproteced calls. - A new and undisputed version of the module mismatch warning - A couple of cleanup and correctness fixes all over the place Yet another step towards full mitigation. There are a few things still missing like the RBS underflow mitigation for Skylake and other small details, but that's being worked on. That said, I'm taking a belated christmas vacation for a week and hope that everything is magically solved when I'm back on Feb 12th" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits) KVM/SVM: Allow direct access to MSR_IA32_SPEC_CTRL KVM/VMX: Allow direct access to MSR_IA32_SPEC_CTRL KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIES KVM/x86: Add IBPB support KVM/x86: Update the reverse_cpuid list to include CPUID_7_EDX x86/speculation: Fix typo IBRS_ATT, which should be IBRS_ALL x86/pti: Mark constant arrays as __initconst x86/spectre: Simplify spectre_v2 command line parsing x86/retpoline: Avoid retpolines for built-in __init functions x86/kvm: Update spectre-v1 mitigation KVM: VMX: make MSR bitmaps per-VCPU x86/paravirt: Remove 'noreplace-paravirt' cmdline option x86/speculation: Use Indirect Branch Prediction Barrier in context switch x86/cpuid: Fix up "virtual" IBRS/IBPB/STIBP feature bits on Intel x86/spectre: Fix spelling mistake: "vunerable"-> "vulnerable" x86/spectre: Report get_user mitigation for spectre_v1 nl80211: Sanitize array index in parse_txq_params vfs, fdtable: Prevent bounds-check bypass via speculative execution x86/syscall: Sanitize syscall table de-references under speculation x86/get_user: Use pointer masking to limit speculation ...
| * | KVM/SVM: Allow direct access to MSR_IA32_SPEC_CTRLKarimAllah Ahmed2018-02-031-0/+88
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Based on a patch from Paolo Bonzini <pbonzini@redhat.com> ] ... basically doing exactly what we do for VMX: - Passthrough SPEC_CTRL to guests (if enabled in guest CPUID) - Save and restore SPEC_CTRL around VMExit and VMEntry only if the guest actually used it. Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jun Nakajima <jun.nakajima@intel.com> Cc: kvm@vger.kernel.org Cc: Dave Hansen <dave.hansen@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Asit Mallick <asit.k.mallick@intel.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ashok Raj <ashok.raj@intel.com> Link: https://lkml.kernel.org/r/1517669783-20732-1-git-send-email-karahmed@amazon.de
| * | KVM/VMX: Allow direct access to MSR_IA32_SPEC_CTRLKarimAllah Ahmed2018-02-033-6/+110
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Based on a patch from Ashok Raj <ashok.raj@intel.com> ] Add direct access to MSR_IA32_SPEC_CTRL for guests. This is needed for guests that will only mitigate Spectre V2 through IBRS+IBPB and will not be using a retpoline+IBPB based approach. To avoid the overhead of saving and restoring the MSR_IA32_SPEC_CTRL for guests that do not actually use the MSR, only start saving and restoring when a non-zero is written to it. No attempt is made to handle STIBP here, intentionally. Filtering STIBP may be added in a future patch, which may require trapping all writes if we don't want to pass it through directly to the guest. [dwmw2: Clean up CPUID bits, save/restore manually, handle reset] Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Jim Mattson <jmattson@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jun Nakajima <jun.nakajima@intel.com> Cc: kvm@vger.kernel.org Cc: Dave Hansen <dave.hansen@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Asit Mallick <asit.k.mallick@intel.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ashok Raj <ashok.raj@intel.com> Link: https://lkml.kernel.org/r/1517522386-18410-5-git-send-email-karahmed@amazon.de
| * | KVM/VMX: Emulate MSR_IA32_ARCH_CAPABILITIESKarimAllah Ahmed2018-02-033-1/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Intel processors use MSR_IA32_ARCH_CAPABILITIES MSR to indicate RDCL_NO (bit 0) and IBRS_ALL (bit 1). This is a read-only MSR. By default the contents will come directly from the hardware, but user-space can still override it. [dwmw2: The bit in kvm_cpuid_7_0_edx_x86_features can be unconditional] Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Reviewed-by: Jim Mattson <jmattson@google.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Jun Nakajima <jun.nakajima@intel.com> Cc: kvm@vger.kernel.org Cc: Dave Hansen <dave.hansen@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Asit Mallick <asit.k.mallick@intel.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Link: https://lkml.kernel.org/r/1517522386-18410-4-git-send-email-karahmed@amazon.de
| * | KVM/x86: Add IBPB supportAshok Raj2018-02-033-3/+116
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Indirect Branch Predictor Barrier (IBPB) is an indirect branch control mechanism. It keeps earlier branches from influencing later ones. Unlike IBRS and STIBP, IBPB does not define a new mode of operation. It's a command that ensures predicted branch targets aren't used after the barrier. Although IBRS and IBPB are enumerated by the same CPUID enumeration, IBPB is very different. IBPB helps mitigate against three potential attacks: * Mitigate guests from being attacked by other guests. - This is addressed by issing IBPB when we do a guest switch. * Mitigate attacks from guest/ring3->host/ring3. These would require a IBPB during context switch in host, or after VMEXIT. The host process has two ways to mitigate - Either it can be compiled with retpoline - If its going through context switch, and has set !dumpable then there is a IBPB in that path. (Tim's patch: https://patchwork.kernel.org/patch/10192871) - The case where after a VMEXIT you return back to Qemu might make Qemu attackable from guest when Qemu isn't compiled with retpoline. There are issues reported when doing IBPB on every VMEXIT that resulted in some tsc calibration woes in guest. * Mitigate guest/ring0->host/ring0 attacks. When host kernel is using retpoline it is safe against these attacks. If host kernel isn't using retpoline we might need to do a IBPB flush on every VMEXIT. Even when using retpoline for indirect calls, in certain conditions 'ret' can use the BTB on Skylake-era CPUs. There are other mitigations available like RSB stuffing/clearing. * IBPB is issued only for SVM during svm_free_vcpu(). VMX has a vmclear and SVM doesn't. Follow discussion here: https://lkml.org/lkml/2018/1/15/146 Please refer to the following spec for more details on the enumeration and control. Refer here to get documentation about mitigations. https://software.intel.com/en-us/side-channel-security-support [peterz: rebase and changelog rewrite] [karahmed: - rebase - vmx: expose PRED_CMD if guest has it in CPUID - svm: only pass through IBPB if guest has it in CPUID - vmx: support !cpu_has_vmx_msr_bitmap()] - vmx: support nested] [dwmw2: Expose CPUID bit too (AMD IBPB only for now as we lack IBRS) PRED_CMD is a write-only MSR] Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: kvm@vger.kernel.org Cc: Asit Mallick <asit.k.mallick@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Jun Nakajima <jun.nakajima@intel.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Link: http://lkml.kernel.org/r/1515720739-43819-6-git-send-email-ashok.raj@intel.com Link: https://lkml.kernel.org/r/1517522386-18410-3-git-send-email-karahmed@amazon.de
| * | KVM/x86: Update the reverse_cpuid list to include CPUID_7_EDXKarimAllah Ahmed2018-02-032-5/+4Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [dwmw2: Stop using KF() for bits in it, too] Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Jim Mattson <jmattson@google.com> Cc: kvm@vger.kernel.org Cc: Radim Krčmář <rkrcmar@redhat.com> Link: https://lkml.kernel.org/r/1517522386-18410-2-git-send-email-karahmed@amazon.de
| * | Merge branch 'msr-bitmaps' of git://git.kernel.org/pub/scm/virt/kvm/kvm into ↵Thomas Gleixner2018-02-031-254/+186Star
| |\ \ | | | | | | | | | | | | | | | | | | | | x86/pti Pull the KVM prerequisites so the IBPB patches apply.
| | * | KVM: VMX: make MSR bitmaps per-VCPUPaolo Bonzini2018-01-311-123/+147
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Place the MSR bitmap in struct loaded_vmcs, and update it in place every time the x2apic or APICv state can change. This is rare and the loop can handle 64 MSRs per iteration, in a similar fashion as nested_vmx_prepare_msr_bitmap. This prepares for choosing, on a per-VM basis, whether to intercept the SPEC_CTRL and PRED_CMD MSRs. Cc: stable@vger.kernel.org # prereq for Spectre mitigation Suggested-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | KVM: VMX: introduce alloc_loaded_vmcsPaolo Bonzini2018-01-271-14/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Group together the calls to alloc_vmcs and loaded_vmcs_init. Soon we'll also allocate an MSR bitmap there. Cc: stable@vger.kernel.org # prereq for Spectre mitigation Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| | * | KVM: nVMX: Eliminate vmcs02 poolJim Mattson2018-01-271-123/+23Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The potential performance advantages of a vmcs02 pool have never been realized. To simplify the code, eliminate the pool. Instead, a single vmcs02 is allocated per VCPU when the VCPU enters VMX operation. Cc: stable@vger.kernel.org # prereq for Spectre mitigation Signed-off-by: Jim Mattson <jmattson@google.com> Signed-off-by: Mark Kanda <mark.kanda@oracle.com> Reviewed-by: Ameya More <ameya.more@oracle.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
| * | | x86/speculation: Fix typo IBRS_ATT, which should be IBRS_ALLDarren Kenny2018-02-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fixes: 117cc7a908c83 ("x86/retpoline: Fill return stack buffer on vmexit") Signed-off-by: Darren Kenny <darren.kenny@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: David Woodhouse <dwmw@amazon.co.uk> Link: https://lkml.kernel.org/r/20180202191220.blvgkgutojecxr3b@starbug-vm.ie.oracle.com
| * | | x86/pti: Mark constant arrays as __initconstArnd Bergmann2018-02-021-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I'm seeing build failures from the two newly introduced arrays that are marked 'const' and '__initdata', which are mutually exclusive: arch/x86/kernel/cpu/common.c:882:43: error: 'cpu_no_speculation' causes a section type conflict with 'e820_table_firmware_init' arch/x86/kernel/cpu/common.c:895:43: error: 'cpu_no_meltdown' causes a section type conflict with 'e820_table_firmware_init' The correct annotation is __initconst. Fixes: fec9434a12f3 ("x86/pti: Do not enable PTI on CPUs which are not vulnerable to Meltdown") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ricardo Neri <ricardo.neri-calderon@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: Thomas Garnier <thgarnie@google.com> Cc: David Woodhouse <dwmw@amazon.co.uk> Link: https://lkml.kernel.org/r/20180202213959.611210-1-arnd@arndb.de
| * | | x86/spectre: Simplify spectre_v2 command line parsingKarimAllah Ahmed2018-02-021-30/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [dwmw2: Use ARRAY_SIZE] Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: peterz@infradead.org Cc: bp@alien8.de Link: https://lkml.kernel.org/r/1517484441-1420-3-git-send-email-dwmw@amazon.co.uk
| * | | x86/retpoline: Avoid retpolines for built-in __init functionsDavid Woodhouse2018-02-021-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's no point in building init code with retpolines, since it runs before any potentially hostile userspace does. And before the retpoline is actually ALTERNATIVEd into place, for much of it. Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: karahmed@amazon.de Cc: peterz@infradead.org Cc: bp@alien8.de Link: https://lkml.kernel.org/r/1517484441-1420-2-git-send-email-dwmw@amazon.co.uk
| * | | x86/kvm: Update spectre-v1 mitigationDan Williams2018-02-011-11/+9Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 75f139aaf896 "KVM: x86: Add memory barrier on vmcs field lookup" added a raw 'asm("lfence");' to prevent a bounds check bypass of 'vmcs_field_to_offset_table'. The lfence can be avoided in this path by using the array_index_nospec() helper designed for these types of fixes. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Andrew Honig <ahonig@google.com> Cc: kvm@vger.kernel.org Cc: Jim Mattson <jmattson@google.com> Link: https://lkml.kernel.org/r/151744959670.6342.3001723920950249067.stgit@dwillia2-desk3.amr.corp.intel.com
| * | | x86/paravirt: Remove 'noreplace-paravirt' cmdline optionJosh Poimboeuf2018-01-312-16/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The 'noreplace-paravirt' option disables paravirt patching, leaving the original pv indirect calls in place. That's highly incompatible with retpolines, unless we want to uglify paravirt even further and convert the paravirt calls to retpolines. As far as I can tell, the option doesn't seem to be useful for much other than introducing surprising corner cases and making the kernel vulnerable to Spectre v2. It was probably a debug option from the early paravirt days. So just remove it. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Jun Nakajima <jun.nakajima@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Asit Mallick <asit.k.mallick@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jason Baron <jbaron@akamai.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Alok Kataria <akataria@vmware.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Dan Williams <dan.j.williams@intel.com> Link: https://lkml.kernel.org/r/20180131041333.2x6blhxirc2kclrq@treble
| * | | x86/speculation: Use Indirect Branch Prediction Barrier in context switchTim Chen2018-01-302-1/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Flush indirect branches when switching into a process that marked itself non dumpable. This protects high value processes like gpg better, without having too high performance overhead. If done naïvely, we could switch to a kernel idle thread and then back to the original process, such as: process A -> idle -> process A In such scenario, we do not have to do IBPB here even though the process is non-dumpable, as we are switching back to the same process after a hiatus. To avoid the redundant IBPB, which is expensive, we track the last mm user context ID. The cost is to have an extra u64 mm context id to track the last mm we were using before switching to the init_mm used by idle. Avoiding the extra IBPB is probably worth the extra memory for this common scenario. For those cases where tlb_defer_switch_to_init_mm() returns true (non PCID), lazy tlb will defer switch to init_mm, so we will not be changing the mm for the process A -> idle -> process A switch. So IBPB will be skipped for this case. Thanks to the reviewers and Andy Lutomirski for the suggestion of using ctx_id which got rid of the problem of mm pointer recycling. Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ak@linux.intel.com Cc: karahmed@amazon.de Cc: arjan@linux.intel.com Cc: torvalds@linux-foundation.org Cc: linux@dominikbrodowski.net Cc: peterz@infradead.org Cc: bp@alien8.de Cc: luto@kernel.org Cc: pbonzini@redhat.com Cc: gregkh@linux-foundation.org Link: https://lkml.kernel.org/r/1517263487-3708-1-git-send-email-dwmw@amazon.co.uk
| * | | x86/cpuid: Fix up "virtual" IBRS/IBPB/STIBP feature bits on IntelDavid Woodhouse2018-01-302-19/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Despite the fact that all the other code there seems to be doing it, just using set_cpu_cap() in early_intel_init() doesn't actually work. For CPUs with PKU support, setup_pku() calls get_cpu_cap() after c->c_init() has set those feature bits. That resets those bits back to what was queried from the hardware. Turning the bits off for bad microcode is easy to fix. That can just use setup_clear_cpu_cap() to force them off for all CPUs. I was less keen on forcing the feature bits *on* that way, just in case of inconsistencies. I appreciate that the kernel is going to get this utterly wrong if CPU features are not consistent, because it has already applied alternatives by the time secondary CPUs are brought up. But at least if setup_force_cpu_cap() isn't being used, we might have a chance of *detecting* the lack of the corresponding bit and either panicking or refusing to bring the offending CPU online. So ensure that the appropriate feature bits are set within get_cpu_cap() regardless of how many extra times it's called. Fixes: 2961298e ("x86/cpufeatures: Clean up Spectre v2 related CPUID flags") Signed-off-by: David Woodhouse <dwmw@amazon.co.uk> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: karahmed@amazon.de Cc: peterz@infradead.org Cc: bp@alien8.de Link: https://lkml.kernel.org/r/1517322623-15261-1-git-send-email-dwmw@amazon.co.uk
| * | | x86/spectre: Fix spelling mistake: "vunerable"-> "vulnerable"Colin Ian King2018-01-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Trivial fix to spelling mistake in pr_err error message text. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andi Kleen <ak@linux.intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: kernel-janitors@vger.kernel.org Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: David Woodhouse <dwmw@amazon.co.uk> Link: https://lkml.kernel.org/r/20180130193218.9271-1-colin.king@canonical.com
| * | | x86/spectre: Report get_user mitigation for spectre_v1Dan Williams2018-01-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reflect the presence of get_user(), __get_user(), and 'syscall' protections in sysfs. The expectation is that new and better tooling will allow the kernel to grow more usages of array_index_nospec(), for now, only claim mitigation for __user pointer de-references. Reported-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: kernel-hardening@lists.openwall.com Cc: gregkh@linuxfoundation.org Cc: torvalds@linux-foundation.org Cc: alan@linux.intel.com Link: https://lkml.kernel.org/r/151727420158.33451.11658324346540434635.stgit@dwillia2-desk3.amr.corp.intel.com
| * | | nl80211: Sanitize array index in parse_txq_paramsDan Williams2018-01-301-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Wireless drivers rely on parse_txq_params to validate that txq_params->ac is less than NL80211_NUM_ACS by the time the low-level driver's ->conf_tx() handler is called. Use a new helper, array_index_nospec(), to sanitize txq_params->ac with respect to speculation. I.e. ensure that any speculation into ->conf_tx() handlers is done with a value of txq_params->ac that is within the bounds of [0, NL80211_NUM_ACS). Reported-by: Christian Lamparter <chunkeey@gmail.com> Reported-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Johannes Berg <johannes@sipsolutions.net> Cc: linux-arch@vger.kernel.org Cc: kernel-hardening@lists.openwall.com Cc: gregkh@linuxfoundation.org Cc: linux-wireless@vger.kernel.org Cc: torvalds@linux-foundation.org Cc: "David S. Miller" <davem@davemloft.net> Cc: alan@linux.intel.com Link: https://lkml.kernel.org/r/151727419584.33451.7700736761686184303.stgit@dwillia2-desk3.amr.corp.intel.com
| * | | vfs, fdtable: Prevent bounds-check bypass via speculative executionDan Williams2018-01-301-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'fd' is a user controlled value that is used as a data dependency to read from the 'fdt->fd' array. In order to avoid potential leaks of kernel memory values, block speculative execution of the instruction stream that could issue reads based on an invalid 'file *' returned from __fcheck_files. Co-developed-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: kernel-hardening@lists.openwall.com Cc: gregkh@linuxfoundation.org Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: torvalds@linux-foundation.org Cc: alan@linux.intel.com Link: https://lkml.kernel.org/r/151727418500.33451.17392199002892248656.stgit@dwillia2-desk3.amr.corp.intel.com
| * | | x86/syscall: Sanitize syscall table de-references under speculationDan Williams2018-01-301-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The syscall table base is a user controlled function pointer in kernel space. Use array_index_nospec() to prevent any out of bounds speculation. While retpoline prevents speculating into a userspace directed target it does not stop the pointer de-reference, the concern is leaking memory relative to the syscall table base, by observing instruction cache behavior. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: kernel-hardening@lists.openwall.com Cc: gregkh@linuxfoundation.org Cc: Andy Lutomirski <luto@kernel.org> Cc: alan@linux.intel.com Link: https://lkml.kernel.org/r/151727417984.33451.1216731042505722161.stgit@dwillia2-desk3.amr.corp.intel.com
| * | | x86/get_user: Use pointer masking to limit speculationDan Williams2018-01-301-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Quoting Linus: I do think that it would be a good idea to very expressly document the fact that it's not that the user access itself is unsafe. I do agree that things like "get_user()" want to be protected, but not because of any direct bugs or problems with get_user() and friends, but simply because get_user() is an excellent source of a pointer that is obviously controlled from a potentially attacking user space. So it's a prime candidate for then finding _subsequent_ accesses that can then be used to perturb the cache. Unlike the __get_user() case get_user() includes the address limit check near the pointer de-reference. With that locality the speculation can be mitigated with pointer narrowing rather than a barrier, i.e. array_index_nospec(). Where the narrowing is performed by: cmp %limit, %ptr sbb %mask, %mask and %mask, %ptr With respect to speculation the value of %ptr is either less than %limit or NULL. Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Cc: kernel-hardening@lists.openwall.com Cc: gregkh@linuxfoundation.org Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: torvalds@linux-foundation.org Cc: alan@linux.intel.com Link: https://lkml.kernel.org/r/151727417469.33451.11804043010080838495.stgit@dwillia2-desk3.amr.corp.intel.com
| * | | x86/uaccess: Use __uaccess_begin_nospec() and uaccess_try_nospecDan Williams2018-01-304-14/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Quoting Linus: I do think that it would be a good idea to very expressly document the fact that it's not that the user access itself is unsafe. I do agree that things like "get_user()" want to be protected, but not because of any direct bugs or problems with get_user() and friends, but simply because get_user() is an excellent source of a pointer that is obviously controlled from a potentially attacking user space. So it's a prime candidate for then finding _subsequent_ accesses that can then be used to perturb the cache. __uaccess_begin_nospec() covers __get_user() and copy_from_iter() where the limit check is far away from the user pointer de-reference. In those cases a barrier_nospec() prevents speculation with a potential pointer to privileged memory. uaccess_try_nospec covers get_user_try. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Suggested-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arch@vger.kernel.org Cc: Kees Cook <keescook@chromium.org> Cc: kernel-hardening@lists.openwall.com Cc: gregkh@linuxfoundation.org Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: alan@linux.intel.com Link: https://lkml.kernel.org/r/151727416953.33451.10508284228526170604.stgit@dwillia2-desk3.amr.corp.intel.com
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-07-04 17:19:51 +0200