- 25 May, 2018 20 commits
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Jens Remus authored
commit fa89adba upstream. zfcp_erp_adapter_reopen() schedules blocking of all of the adapter's rports via zfcp_scsi_schedule_rports_block() and enqueues a reopen adapter ERP action via zfcp_erp_action_enqueue(). Both are separately processed asynchronously and concurrently. Blocking of rports is done in a kworker by zfcp_scsi_rport_work(). It calls zfcp_scsi_rport_block(), which then traces a DBF REC "scpdely" via zfcp_dbf_rec_trig(). zfcp_dbf_rec_trig() acquires the DBF REC spin lock and then iterates with list_for_each() over the adapter's ERP ready list without holding the ERP lock. This opens a race window in which the current list entry can be moved to another list, causing list_for_each() to iterate forever on the wrong list, as the erp_ready_head is never encountered as terminal condition. Meanwhile the ERP action can be processed in the ERP thread by zfcp_erp_thread(). It calls zfcp_erp_strategy(), which acquires the ERP lock and then calls zfcp_erp_action_to_running() to move the ERP action from the ready to the running list. zfcp_erp_action_to_running() can move the ERP action using list_move() just during the aforementioned race window. It then traces a REC RUN "erator1" via zfcp_dbf_rec_run(). zfcp_dbf_rec_run() tries to acquire the DBF REC spin lock. If this is held by the infinitely looping kworker, it effectively spins forever. Example Sequence Diagram: Process ERP Thread rport_work ------------------- ------------------- ------------------- zfcp_erp_adapter_reopen() zfcp_erp_adapter_block() zfcp_scsi_schedule_rports_block() lock ERP zfcp_scsi_rport_work() zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_ADAPTER) list_add_tail() on ready !(rport_task==RPORT_ADD) wake_up() ERP thread zfcp_scsi_rport_block() zfcp_dbf_rec_trig() zfcp_erp_strategy() zfcp_dbf_rec_trig() unlock ERP lock DBF REC zfcp_erp_wait() lock ERP | zfcp_erp_action_to_running() | list_for_each() ready | list_move() current entry | ready to running | zfcp_dbf_rec_run() endless loop over running | zfcp_dbf_rec_run_lvl() | lock DBF REC spins forever Any adapter recovery can trigger this, such as setting the device offline or reboot. V4.9 commit 4eeaa4f3 ("zfcp: close window with unblocked rport during rport gone") introduced additional tracing of (un)blocking of rports. It missed that the adapter->erp_lock must be held when calling zfcp_dbf_rec_trig(). This fix uses the approach formerly introduced by commit aa0fec62 ("[SCSI] zfcp: Fix sparse warning by providing new entry in dbf") that got later removed by commit ae0904f6 ("[SCSI] zfcp: Redesign of the debug tracing for recovery actions."). Introduce zfcp_dbf_rec_trig_lock(), a wrapper for zfcp_dbf_rec_trig() that acquires and releases the adapter->erp_lock for read. Reported-by:
Sebastian Ott <sebott@linux.ibm.com> Signed-off-by:
Jens Remus <jremus@linux.ibm.com> Fixes: 4eeaa4f3 ("zfcp: close window with unblocked rport during rport gone") Cc: <stable@vger.kernel.org> # 2.6.32+ Reviewed-by:
Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by:
Steffen Maier <maier@linux.ibm.com> Signed-off-by:
Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Alexander Potapenko authored
commit a45b599a upstream. This shall help avoid copying uninitialized memory to the userspace when calling ioctl(fd, SG_IO) with an empty command. Reported-by: syzbot+7d26fc1eea198488deab@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by:
Alexander Potapenko <glider@google.com> Acked-by:
Douglas Gilbert <dgilbert@interlog.com> Reviewed-by:
Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by:
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Jason Yan authored
commit 318aaf34 upstream. When ata device doing EH, some commands still attached with tasks are not passed to libata when abort failed or recover failed, so libata did not handle these commands. After these commands done, sas task is freed, but ata qc is not freed. This will cause ata qc leak and trigger a warning like below: WARNING: CPU: 0 PID: 28512 at drivers/ata/libata-eh.c:4037 ata_eh_finish+0xb4/0xcc CPU: 0 PID: 28512 Comm: kworker/u32:2 Tainted: G W OE 4.14.0#1 ...... Call trace: [<ffff0000088b7bd0>] ata_eh_finish+0xb4/0xcc [<ffff0000088b8420>] ata_do_eh+0xc4/0xd8 [<ffff0000088b8478>] ata_std_error_handler+0x44/0x8c [<ffff0000088b8068>] ata_scsi_port_error_handler+0x480/0x694 [<ffff000008875fc4>] async_sas_ata_eh+0x4c/0x80 [<ffff0000080f6be8>] async_run_entry_fn+0x4c/0x170 [<ffff0000080ebd70>] process_one_work+0x144/0x390 [<ffff0000080ec100>] worker_thread+0x144/0x418 [<ffff0000080f2c98>] kthread+0x10c/0x138 [<ffff0000080855dc>] ret_from_fork+0x10/0x18 If ata qc leaked too many, ata tag allocation will fail and io blocked for ever. As suggested by Dan Williams, defer ata device commands to libata and merge sas_eh_finish_cmd() with sas_eh_defer_cmd(). libata will handle ata qcs correctly after this. Signed-off-by:
Jason Yan <yanaijie@huawei.com> CC: Xiaofei Tan <tanxiaofei@huawei.com> CC: John Garry <john.garry@huawei.com> CC: Dan Williams <dan.j.williams@intel.com> Reviewed-by:
Dan Williams <dan.j.williams@intel.com> Signed-off-by:
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Martin Schwidefsky authored
[ Upstream commit de5cb6eb ] The BPF JIT need safe guarding against spectre v2 in the sk_load_xxx assembler stubs and the indirect branches generated by the JIT itself need to be converted to expolines. Signed-off-by:
Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by:
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Martin Schwidefsky authored
[ Upstream commit 6deaa3bb ] The BPF JIT uses a 'b <disp>(%r<x>)' instruction in the definition of the sk_load_word and sk_load_half functions. Add support for branch-on-condition instructions contained in the thunk code of an expoline. Signed-off-by:
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Martin Schwidefsky authored
[ Upstream commit 4253b0e0 ] The nospec-branch.c file is compiled without the gcc options to generate expoline thunks. The return branch of the sysfs show functions cpu_show_spectre_v1 and cpu_show_spectre_v2 is an indirect branch as well. These need to be compiled with expolines. Move the sysfs functions for spectre reporting to a separate file and loose an '.' for one of the messages. Cc: stable@vger.kernel.org # 4.16 Fixes: d424986f ("s390: add sysfs attributes for spectre") Signed-off-by:
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Martin Schwidefsky authored
[ Upstream commit c50c84c3 ] The assember code in arch/s390/kernel uses a few more indirect branches which need to be done with execute trampolines for CONFIG_EXPOLINE=y. Cc: stable@vger.kernel.org # 4.16 Fixes: f19fbd5e ("s390: introduce execute-trampolines for branches") Reviewed-by:
Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by:
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Martin Schwidefsky authored
[ Upstream commit 23a4d7fd ] The return from the ftrace_stub, _mcount, ftrace_caller and return_to_handler functions is done with "br %r14" and "br %r1". These are indirect branches as well and need to use execute trampolines for CONFIG_EXPOLINE=y. The ftrace_caller function is a special case as it returns to the start of a function and may only use %r0 and %r1. For a pre z10 machine the standard execute trampoline uses a LARL + EX to do this, but this requires *two* registers in the range %r1..%r15. To get around this the 'br %r1' located in the lowcore is used, then the EX instruction does not need an address register. But the lowcore trick may only be used for pre z14 machines, with noexec=on the mapping for the first page may not contain instructions. The solution for that is an ALTERNATIVE in the expoline THUNK generated by 'GEN_BR_THUNK %r1' to switch to EXRL, this relies on the fact that a machine that supports noexec=on has EXRL as well. Cc: stable@vger.kernel.org # 4.16 Fixes: f19fbd5e ("s390: introduce execute-trampolines for branches") Signed-off-by:
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Martin Schwidefsky authored
[ Upstream commit 97489e06 ] The return from the memmove, memset, memcpy, __memset16, __memset32 and __memset64 functions are done with "br %r14". These are indirect branches as well and need to use execute trampolines for CONFIG_EXPOLINE=y. Cc: stable@vger.kernel.org # 4.16 Fixes: f19fbd5e ("s390: introduce execute-trampolines for branches") Reviewed-by:
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Martin Schwidefsky authored
[ Upstream commit 467a3bf2 ] The return from the crc32_le_vgfm_16/crc32c_le_vgfm_16 and the crc32_be_vgfm_16 functions are done with "br %r14". These are indirect branches as well and need to use execute trampolines for CONFIG_EXPOLINE=y. Cc: stable@vger.kernel.org # 4.16 Fixes: f19fbd5e ("s390: introduce execute-trampolines for branches") Reviewed-by:
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Martin Schwidefsky authored
[ Upstream commit 6dd85fbb ] To be able to use the expoline branches in different assembler files move the associated macros from entry.S to a new header nospec-insn.h. While we are at it make the macros a bit nicer to use. Cc: stable@vger.kernel.org # 4.16 Fixes: f19fbd5e ("s390: introduce execute-trampolines for branches") Signed-off-by:
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Martin Schwidefsky authored
[ Upstream commit fba9eb79 ] Add a header with macros usable in assembler files to emit alternative code sequences. It works analog to the alternatives for inline assmeblies in C files, with the same restrictions and capabilities. The syntax is ALTERNATIVE "<default instructions sequence>", \ "<alternative instructions sequence>", \ "<features-bit>" and ALTERNATIVE_2 "<default instructions sequence>", \ "<alternative instructions sqeuence #1>", \ "<feature-bit #1>", "<alternative instructions sqeuence #2>", \ "<feature-bit #2>" Reviewed-by:
Vasily Gorbik <gor@linux.vnet.ibm.com> Signed-off-by:
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Al Viro authored
commit 5aa1437d upstream. open file, unlink it, then use ioctl(2) to make it immutable or append only. Now close it and watch the blocks *not* freed... Immutable/append-only checks belong in ->setattr(). Note: the bug is old and backport to anything prior to 737f2e93 ("ext2: convert to use the new truncate convention") will need these checks lifted into ext2_setattr(). Cc: stable@kernel.org Signed-off-by:
Al Viro <viro@zeniv.linux.org.uk> Signed-off-by:
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hpreg@vmware.com authored
[ Upstream commit f3002c13 ] The gen bits must be read first from (resp. written last to) DMA memory. The proper way to enforce this on Linux is to call dma_rmb() (resp. dma_wmb()). Signed-off-by:
Regis Duchesne <hpreg@vmware.com> Acked-by:
Ronak Doshi <doshir@vmware.com> Signed-off-by:
David S. Miller <davem@davemloft.net> Signed-off-by:
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hpreg@vmware.com authored
[ Upstream commit 61aeecea ] The DMA mask must be set before, not after, the first DMA map operation, or the first DMA map operation could in theory fail on some systems. Fixes: b0eb57cb ("VMXNET3: Add support for virtual IOMMU") Signed-off-by:
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Eric Dumazet authored
[ Upstream commit 7f582b24 ] syzkaller found a reliable way to crash the host, hitting a BUG() in __tcp_retransmit_skb() Malicous MSG_FASTOPEN is the root cause. We need to purge write queue in tcp_connect_init() at the point we init snd_una/write_seq. This patch also replaces the BUG() by a less intrusive WARN_ON_ONCE() kernel BUG at net/ipv4/tcp_output.c:2837! invalid opcode: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 0 PID: 5276 Comm: syz-executor0 Not tainted 4.17.0-rc3+ #51 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__tcp_retransmit_skb+0x2992/0x2eb0 net/ipv4/tcp_output.c:2837 RSP: 0000:ffff8801dae06ff8 EFLAGS: 00010206 RAX: ffff8801b9fe61c0 RBX: 00000000ffc18a16 RCX: ffffffff864e1a49 RDX: 0000000000000100 RSI: ffffffff864e2e12 RDI: 0000000000000005 RBP: ffff8801dae073a0 R08: ffff8801b9fe61c0 R09: ffffed0039c40dd2 R10: ffffed0039c40dd2 R11: ffff8801ce206e93 R12: 00000000421eeaad R13: ffff8801ce206d4e R14: ffff8801ce206cc0 R15: ffff8801cd4f4a80 FS: 0000000000000000(0000) GS:ffff8801dae00000(0063) knlGS:00000000096bc900 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 0000000020000000 CR3: 00000001c47b6000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> tcp_retransmit_skb+0x2e/0x250 net/ipv4/tcp_output.c:2923 tcp_retransmit_timer+0xc50/0x3060 net/ipv4/tcp_timer.c:488 tcp_write_timer_handler+0x339/0x960 net/ipv4/tcp_timer.c:573 tcp_write_timer+0x111/0x1d0 net/ipv4/tcp_timer.c:593 call_timer_fn+0x230/0x940 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x79e/0xc50 kernel/time/timer.c:1666 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285 invoke_softirq kernel/softirq.c:365 [inline] irq_exit+0x1d1/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:525 [inline] smp_apic_timer_interrupt+0x17e/0x710 arch/x86/kernel/apic/apic.c:1052 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863 Fixes: cf60af03 ("net-tcp: Fast Open client - sendmsg(MSG_FASTOPEN)") Signed-off-by:
Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Reported-by:
syzbot <syzkaller@googlegroups.com> Acked-by:
Neal Cardwell <ncardwell@google.com> Signed-off-by:
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Eric Dumazet authored
[ Upstream commit 9709020c ] We must not call sock_diag_has_destroy_listeners(sk) on a socket that has no reference on net structure. BUG: KASAN: use-after-free in sock_diag_has_destroy_listeners include/linux/sock_diag.h:75 [inline] BUG: KASAN: use-after-free in __sk_free+0x329/0x340 net/core/sock.c:1609 Read of size 8 at addr ffff88018a02e3a0 by task swapper/1/0 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.17.0-rc5+ #54 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1b9/0x294 lib/dump_stack.c:113 print_address_description+0x6c/0x20b mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433 sock_diag_has_destroy_listeners include/linux/sock_diag.h:75 [inline] __sk_free+0x329/0x340 net/core/sock.c:1609 sk_free+0x42/0x50 net/core/sock.c:1623 sock_put include/net/sock.h:1664 [inline] reqsk_free include/net/request_sock.h:116 [inline] reqsk_put include/net/request_sock.h:124 [inline] inet_csk_reqsk_queue_drop_and_put net/ipv4/inet_connection_sock.c:672 [inline] reqsk_timer_handler+0xe27/0x10e0 net/ipv4/inet_connection_sock.c:739 call_timer_fn+0x230/0x940 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x79e/0xc50 kernel/time/timer.c:1666 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285 invoke_softirq kernel/softirq.c:365 [inline] irq_exit+0x1d1/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:525 [inline] smp_apic_timer_interrupt+0x17e/0x710 arch/x86/kernel/apic/apic.c:1052 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863 </IRQ> RIP: 0010:native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:54 RSP: 0018:ffff8801d9ae7c38 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: 1ffff1003b35cf8a RCX: 0000000000000000 RDX: 1ffffffff11a30d0 RSI: 0000000000000001 RDI: ffffffff88d18680 RBP: ffff8801d9ae7c38 R08: ffffed003b5e46c3 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 R13: ffff8801d9ae7cf0 R14: ffffffff897bef20 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline] default_idle+0xc2/0x440 arch/x86/kernel/process.c:354 arch_cpu_idle+0x10/0x20 arch/x86/kernel/process.c:345 default_idle_call+0x6d/0x90 kernel/sched/idle.c:93 cpuidle_idle_call kernel/sched/idle.c:153 [inline] do_idle+0x395/0x560 kernel/sched/idle.c:262 cpu_startup_entry+0x104/0x120 kernel/sched/idle.c:368 start_secondary+0x426/0x5b0 arch/x86/kernel/smpboot.c:269 secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:242 Allocated by task 4557: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3554 kmem_cache_zalloc include/linux/slab.h:691 [inline] net_alloc net/core/net_namespace.c:383 [inline] copy_net_ns+0x159/0x4c0 net/core/net_namespace.c:423 create_new_namespaces+0x69d/0x8f0 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xc3/0x1f0 kernel/nsproxy.c:206 ksys_unshare+0x708/0xf90 kernel/fork.c:2408 __do_sys_unshare kernel/fork.c:2476 [inline] __se_sys_unshare kernel/fork.c:2474 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2474 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 69: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x86/0x2d0 mm/slab.c:3756 net_free net/core/net_namespace.c:399 [inline] net_drop_ns.part.14+0x11a/0x130 net/core/net_namespace.c:406 net_drop_ns net/core/net_namespace.c:405 [inline] cleanup_net+0x6a1/0xb20 net/core/net_namespace.c:541 process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145 worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279 kthread+0x345/0x410 kernel/kthread.c:240 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 The buggy address belongs to the object at ffff88018a02c140 which belongs to the cache net_namespace of size 8832 The buggy address is located 8800 bytes inside of 8832-byte region [ffff88018a02c140, ffff88018a02e3c0) The buggy address belongs to the page: page:ffffea0006280b00 count:1 mapcount:0 mapping:ffff88018a02c140 index:0x0 compound_mapcount: 0 flags: 0x2fffc0000008100(slab|head) raw: 02fffc0000008100 ffff88018a02c140 0000000000000000 0000000100000001 raw: ffffea00062a1320 ffffea0006268020 ffff8801d9bdde40 0000000000000000 page dumped because: kasan: bad access detected Fixes: b922622e ("sock_diag: don't broadcast kernel sockets") Signed-off-by:
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Willem de Bruijn authored
[ Upstream commit b84bbaf7 ] Packet sockets allow construction of packets shorter than dev->hard_header_len to accommodate protocols with variable length link layer headers. These packets are padded to dev->hard_header_len, because some device drivers interpret that as a minimum packet size. packet_snd reserves dev->hard_header_len bytes on allocation. SOCK_DGRAM sockets call skb_push in dev_hard_header() to ensure that link layer headers are stored in the reserved range. SOCK_RAW sockets do the same in tpacket_snd, but not in packet_snd. Syzbot was able to send a zero byte packet to a device with massive 116B link layer header, causing padding to cross over into skb_shinfo. Fix this by writing from the start of the llheader reserved range also in the case of packet_snd/SOCK_RAW. Update skb_set_network_header to the new offset. This also corrects it for SOCK_DGRAM, where it incorrectly double counted reserve due to the skb_push in dev_hard_header. Fixes: 9ed988cd ("packet: validate variable length ll headers") Reported-by: syzbot+71d74a5406d02057d559@syzkaller.appspotmail.com Signed-off-by:
Willem de Bruijn <willemb@google.com> Signed-off-by:
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Willem de Bruijn authored
[ Upstream commit 113f99c3 ] Device features may change during transmission. In particular with corking, a device may toggle scatter-gather in between allocating and writing to an skb. Do not unconditionally assume that !NETIF_F_SG at write time implies that the same held at alloc time and thus the skb has sufficient tailroom. This issue predates git history. Fixes: 1da177e4 ("Linux-2.6.12-rc2") Reported-by:
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Tarick Bedeir authored
[ Upstream commit 57f6f99f ] Avoid exiting the function with a lingering sysfs file (if the first call to device_create_file() fails while the second succeeds), and avoid calling devlink_port_unregister() twice. In other words, either mlx4_init_port_info() succeeds and returns zero, or it fails, returns non-zero, and requires no cleanup. Fixes: 096335b3 ("mlx4_core: Allow dynamic MTU configuration for IB ports") Signed-off-by:
Tarick Bedeir <tarick@google.com> Reviewed-by:
Leon Romanovsky <leonro@mellanox.com> Reviewed-by:
Tariq Toukan <tariqt@mellanox.com> Signed-off-by:
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- 22 May, 2018 20 commits
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Greg Kroah-Hartman authored
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Konrad Rzeszutek Wilk authored
commit 240da953 upstream The "336996 Speculative Execution Side Channel Mitigations" from May defines this as SSB_NO, hence lets sync-up. Signed-off-by:
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by:
Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
David Woodhouse <dwmw@amazon.co.uk> Signed-off-by:
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Tom Lendacky authored
commit bc226f07 upstream Expose the new virtualized architectural mechanism, VIRT_SSBD, for using speculative store bypass disable (SSBD) under SVM. This will allow guests to use SSBD on hardware that uses non-architectural mechanisms for enabling SSBD. [ tglx: Folded the migration fixup from Paolo Bonzini ] Signed-off-by:
Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by:
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Thomas Gleixner authored
commit 47c61b39 upstream Add the necessary logic for supporting the emulated VIRT_SPEC_CTRL MSR to x86_virt_spec_ctrl(). If either X86_FEATURE_LS_CFG_SSBD or X86_FEATURE_VIRT_SPEC_CTRL is set then use the new guest_virt_spec_ctrl argument to check whether the state must be modified on the host. The update reuses speculative_store_bypass_update() so the ZEN-specific sibling coordination can be reused. Signed-off-by:
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Thomas Gleixner authored
commit be6fcb54 upstream x86_spec_ctrL_mask is intended to mask out bits from a MSR_SPEC_CTRL value which are not to be modified. However the implementation is not really used and the bitmask was inverted to make a check easier, which was removed in "x86/bugs: Remove x86_spec_ctrl_set()" Aside of that it is missing the STIBP bit if it is supported by the platform, so if the mask would be used in x86_virt_spec_ctrl() then it would prevent a guest from setting STIBP. Add the STIBP bit if supported and use the mask in x86_virt_spec_ctrl() to sanitize the value which is supplied by the guest. Signed-off-by:
Borislav Petkov <bp@suse.de> Signed-off-by:
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Thomas Gleixner authored
commit 4b59bdb5 upstream x86_spec_ctrl_set() is only used in bugs.c and the extra mask checks there provide no real value as both call sites can just write x86_spec_ctrl_base to MSR_SPEC_CTRL. x86_spec_ctrl_base is valid and does not need any extra masking or checking. Signed-off-by:
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Thomas Gleixner authored
commit fa8ac498 upstream x86_spec_ctrl_base is the system wide default value for the SPEC_CTRL MSR. x86_spec_ctrl_get_default() returns x86_spec_ctrl_base and was intended to prevent modification to that variable. Though the variable is read only after init and globaly visible already. Remove the function and export the variable instead. Signed-off-by:
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Borislav Petkov authored
commit cc69b349 upstream Function bodies are very similar and are going to grow more almost identical code. Add a bool arg to determine whether SPEC_CTRL is being set for the guest or restored to the host. No functional changes. Signed-off-by:
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Thomas Gleixner authored
commit 0270be3e upstream The upcoming support for the virtual SPEC_CTRL MSR on AMD needs to reuse speculative_store_bypass_update() to avoid code duplication. Add an argument for supplying a thread info (TIF) value and create a wrapper speculative_store_bypass_update_current() which is used at the existing call site. Signed-off-by:
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Tom Lendacky authored
commit 11fb0683 upstream Some AMD processors only support a non-architectural means of enabling speculative store bypass disable (SSBD). To allow a simplified view of this to a guest, an architectural definition has been created through a new CPUID bit, 0x80000008_EBX[25], and a new MSR, 0xc001011f. With this, a hypervisor can virtualize the existence of this definition and provide an architectural method for using SSBD to a guest. Add the new CPUID feature, the new MSR and update the existing SSBD support to use this MSR when present. Signed-off-by:
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Thomas Gleixner authored
commit ccbcd267 upstream AMD is proposing a VIRT_SPEC_CTRL MSR to handle the Speculative Store Bypass Disable via MSR_AMD64_LS_CFG so that guests do not have to care about the bit position of the SSBD bit and thus facilitate migration. Also, the sibling coordination on Family 17H CPUs can only be done on the host. Extend x86_spec_ctrl_set_guest() and x86_spec_ctrl_restore_host() with an extra argument for the VIRT_SPEC_CTRL MSR. Hand in 0 from VMX and in SVM add a new virt_spec_ctrl member to the CPU data structure which is going to be used in later patches for the actual implementation. Signed-off-by:
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Thomas Gleixner authored
commit 1f50ddb4 upstream The AMD64_LS_CFG MSR is a per core MSR on Family 17H CPUs. That means when hyperthreading is enabled the SSBD bit toggle needs to take both cores into account. Otherwise the following situation can happen: CPU0 CPU1 disable SSB disable SSB enable SSB <- Enables it for the Core, i.e. for CPU0 as well So after the SSB enable on CPU1 the task on CPU0 runs with SSB enabled again. On Intel the SSBD control is per core as well, but the synchronization logic is implemented behind the per thread SPEC_CTRL MSR. It works like this: CORE_SPEC_CTRL = THREAD0_SPEC_CTRL | THREAD1_SPEC_CTRL i.e. if one of the threads enables a mitigation then this affects both and the mitigation is only disabled in the core when both threads disabled it. Add the necessary synchronization logic for AMD family 17H. Unfortunately that requires a spinlock to serialize the access to the MSR, but the locks are only shared between siblings. Signed-off-by:
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Thomas Gleixner authored
commit d1035d97 upstream Add a ZEN feature bit so family-dependent static_cpu_has() optimizations can be built for ZEN. Signed-off-by:
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Borislav Petkov authored
commit f7f3dc00 upstream CPUID Fn8000_0007_EDX[CPB] is wrongly 0 on models up to B1. But they do support CPB (AMD's Core Performance Boosting cpufreq CPU feature), so fix that. Signed-off-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
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Thomas Gleixner authored
commit 52817587 upstream The SSBD enumeration is similarly to the other bits magically shared between Intel and AMD though the mechanisms are different. Make X86_FEATURE_SSBD synthetic and set it depending on the vendor specific features or family dependent setup. Change the Intel bit to X86_FEATURE_SPEC_CTRL_SSBD to denote that SSBD is controlled via MSR_SPEC_CTRL and fix up the usage sites. Signed-off-by:
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Thomas Gleixner authored
commit 7eb8956a upstream The availability of the SPEC_CTRL MSR is enumerated by a CPUID bit on Intel and implied by IBRS or STIBP support on AMD. That's just confusing and in case an AMD CPU has IBRS not supported because the underlying problem has been fixed but has another bit valid in the SPEC_CTRL MSR, the thing falls apart. Add a synthetic feature bit X86_FEATURE_MSR_SPEC_CTRL to denote the availability on both Intel and AMD. While at it replace the boot_cpu_has() checks with static_cpu_has() where possible. This prevents late microcode loading from exposing SPEC_CTRL, but late loading is already very limited as it does not reevaluate the mitigation options and other bits and pieces. Having static_cpu_has() is the simplest and least fragile solution. Signed-off-by:
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Borislav Petkov authored
commit e7c587da upstream Intel and AMD have different CPUID bits hence for those use synthetic bits which get set on the respective vendor's in init_speculation_control(). So that debacles like what the commit message of c65732e4 ("x86/cpu: Restore CPUID_8000_0008_EBX reload") talks about don't happen anymore. Signed-off-by:
Jörg Otte <jrg.otte@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Link: https://lkml.kernel.org/r/20180504161815.GG9257@pd.tnicSigned-off-by:
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Thomas Gleixner authored
commit 15e6c22f upstream svm_vcpu_run() invokes x86_spec_ctrl_restore_host() after VMEXIT, but before the host GS is restored. x86_spec_ctrl_restore_host() uses 'current' to determine the host SSBD state of the thread. 'current' is GS based, but host GS is not yet restored and the access causes a triple fault. Move the call after the host GS restore. Fixes: 885f82bf x86/process: Allow runtime control of Speculative Store Bypass Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com> Signed-off-by:
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Jim Mattson authored
commit 5f2b745f upstream Cast val and (val >> 32) to (u32), so that they fit in a general-purpose register in both 32-bit and 64-bit code. [ tglx: Made it u32 instead of uintptr_t ] Fixes: c65732e4 ("x86/cpu: Restore CPUID_8000_0008_EBX reload") Signed-off-by:
Jim Mattson <jmattson@google.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
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Konrad Rzeszutek Wilk authored
commit ffed645e upstream Fixes: 7bb4d366 ("x86/bugs: Make cpu_show_common() static") Fixes: 24f7fc83 ("x86/bugs: Provide boot parameters for the spec_store_bypass_disable mitigation") Signed-off-by:
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