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* crypto: ghash-clmulni: specify context size for ghash async algorithmAndrey Ryabinin2015-10-131-0/+1
| | | | | | | | | | | | | commit 71c6da846be478a61556717ef1ee1cea91f5d6a8 upstream. Currently context size (cra_ctxsize) doesn't specified for ghash_async_alg. Which means it's zero. Thus crypto_create_tfm() doesn't allocate needed space for ghash_async_ctx, so any read/write to ctx (e.g. in ghash_async_init_tfm()) is not valid. Signed-off-by: Andrey Ryabinin <aryabinin@odin.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* KVM: MMU: fix validation of mmio page faultXiao Guangrong2015-10-131-45/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 6f691251c0350ac52a007c54bf3ef62e9d8cdc5e upstream. We got the bug that qemu complained with "KVM: unknown exit, hardware reason 31" and KVM shown these info: [84245.284948] EPT: Misconfiguration. [84245.285056] EPT: GPA: 0xfeda848 [84245.285154] ept_misconfig_inspect_spte: spte 0x5eaef50107 level 4 [84245.285344] ept_misconfig_inspect_spte: spte 0x5f5fadc107 level 3 [84245.285532] ept_misconfig_inspect_spte: spte 0x5141d18107 level 2 [84245.285723] ept_misconfig_inspect_spte: spte 0x52e40dad77 level 1 This is because we got a mmio #PF and the handler see the mmio spte becomes normal (points to the ram page) However, this is valid after introducing fast mmio spte invalidation which increases the generation-number instead of zapping mmio sptes, a example is as follows: 1. QEMU drops mmio region by adding a new memslot 2. invalidate all mmio sptes 3. VCPU 0 VCPU 1 access the invalid mmio spte access the region originally was MMIO before set the spte to the normal ram map mmio #PF check the spte and see it becomes normal ram mapping !!! This patch fixes the bug just by dropping the check in mmio handler, it's good for backport. Full check will be introduced in later patches Reported-by: Pavel Shirshov <ru.pchel@gmail.com> Tested-by: Pavel Shirshov <ru.pchel@gmail.com> Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.2: error code from handle_mmio_page_fault_common() was not named] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/ldt: Further fix FPU emulationAndy Lutomirski2015-10-131-1/+1
| | | | | | | | | | | | | | | commit 12e244f4b550498bbaf654a52f93633f7dde2dc7 upstream. The previous fix confused a selector with a segment prefix. Fix it. Compile-tested only. Cc: Juergen Gross <jgross@suse.com> Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Fixes: 4809146b86c3 ("x86/ldt: Correct FPU emulation access to LDT") Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/ldt: Correct FPU emulation access to LDTJuergen Gross2015-10-133-7/+20
| | | | | | | | | | | | | | | | | | | | commit 4809146b86c3d41ce588fdb767d021e2a80600dd upstream. Commit 37868fe113ff ("x86/ldt: Make modify_ldt synchronous") introduced a new struct ldt_struct anchored at mm->context.ldt. Adapt the x86 fpu emulation code to use that new structure. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Andy Lutomirski <luto@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: billm@melbpc.org.au Link: http://lkml.kernel.org/r/1438883674-1240-1-git-send-email-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/ldt: Correct LDT access in single stepping logicJuergen Gross2015-10-131-2/+2
| | | | | | | | | | | | | | | | | | | | commit 136d9d83c07c5e30ac49fc83b27e8c4842f108fc upstream. Commit 37868fe113ff ("x86/ldt: Make modify_ldt synchronous") introduced a new struct ldt_struct anchored at mm->context.ldt. convert_ip_to_linear() was changed to reflect this, but indexing into the ldt has to be changed as the pointer is no longer void *. Signed-off-by: Juergen Gross <jgross@suse.com> Reviewed-by: Andy Lutomirski <luto@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bp@suse.de Link: http://lkml.kernel.org/r/1438848278-12906-1-git-send-email-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/ldt: Make modify_ldt synchronousAndy Lutomirski2015-10-138-146/+205
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 37868fe113ff2ba814b3b4eb12df214df555f8dc upstream. modify_ldt() has questionable locking and does not synchronize threads. Improve it: redesign the locking and synchronize all threads' LDTs using an IPI on all modifications. This will dramatically slow down modify_ldt in multithreaded programs, but there shouldn't be any multithreaded programs that care about modify_ldt's performance in the first place. This fixes some fallout from the CVE-2015-5157 fixes. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Borislav Petkov <bp@suse.de> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: security@kernel.org <security@kernel.org> Cc: xen-devel <xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/4c6978476782160600471bd865b318db34c7b628.1438291540.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> [bwh: Backported to 3.2: - Adjust context - Drop comment changes in switch_mm() - Drop changes to get_segment_base() in arch/x86/kernel/cpu/perf_event.c - Open-code lockless_dereference(), smp_store_release(), on_each_cpu_mask()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/xen: Probe target addresses in set_aliased_prot() before the hypercallAndy Lutomirski2015-08-121-0/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit aa1acff356bbedfd03b544051f5b371746735d89 upstream. The update_va_mapping hypercall can fail if the VA isn't present in the guest's page tables. Under certain loads, this can result in an OOPS when the target address is in unpopulated vmap space. While we're at it, add comments to help explain what's going on. This isn't a great long-term fix. This code should probably be changed to use something like set_memory_ro. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Vrabel <dvrabel@cantab.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: security@kernel.org <security@kernel.org> Cc: xen-devel <xen-devel@lists.xen.org> Link: http://lkml.kernel.org/r/0b0e55b995cda11e7829f140b833ef932fcabe3a.1438291540.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* KVM: x86: properly restore LVT0Radim Krčmář2015-08-121-0/+1
| | | | | | | | | | | | | | commit db1385624c686fe99fe2d1b61a36e1537b915d08 upstream. Legacy NMI watchdog didn't work after migration/resume, because vapics_in_nmi_mode was left at 0. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.2: - Adjust context - s/kvm_apic_get_reg/apic_get_reg/] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* KVM: x86: make vapics_in_nmi_mode atomicRadim Krčmář2015-08-123-4/+4
| | | | | | | | | | | | | | commit 42720138b06301cc8a7ee8a495a6d021c4b6a9bc upstream. Writes were a bit racy, but hard to turn into a bug at the same time. (Particularly because modern Linux doesn't use this feature anymore.) Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> [Actually the next patch makes it much, much easier to trigger the race so I'm including this one for stable@ as well. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/reboot: Fix a warning message triggered by stop_other_cpus()Feng Tang2015-08-071-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 55c844a4dd16a4d1fdc0cf2a283ec631a02ec448 upstream. When rebooting our 24 CPU Westmere servers with 3.4-rc6, we always see this warning msg: Restarting system. machine restart ------------[ cut here ]------------ WARNING: at arch/x86/kernel/smp.c:125 native_smp_send_reschedule+0x74/0xa7() Hardware name: X8DTN Modules linked in: igb [last unloaded: scsi_wait_scan] Pid: 1, comm: systemd-shutdow Not tainted 3.4.0-rc6+ #22 Call Trace: <IRQ> [<ffffffff8102a41f>] warn_slowpath_common+0x7e/0x96 [<ffffffff8102a44c>] warn_slowpath_null+0x15/0x17 [<ffffffff81018cf7>] native_smp_send_reschedule+0x74/0xa7 [<ffffffff810561c1>] trigger_load_balance+0x279/0x2a6 [<ffffffff81050112>] scheduler_tick+0xe0/0xe9 [<ffffffff81036768>] update_process_times+0x60/0x70 [<ffffffff81062f2f>] tick_sched_timer+0x68/0x92 [<ffffffff81046e33>] __run_hrtimer+0xb3/0x13c [<ffffffff81062ec7>] ? tick_nohz_handler+0xd0/0xd0 [<ffffffff810474f2>] hrtimer_interrupt+0xdb/0x198 [<ffffffff81019a35>] smp_apic_timer_interrupt+0x81/0x94 [<ffffffff81655187>] apic_timer_interrupt+0x67/0x70 <EOI> [<ffffffff8101a3c4>] ? default_send_IPI_mask_allbutself_phys+0xb4/0xc4 [<ffffffff8101c680>] physflat_send_IPI_allbutself+0x12/0x14 [<ffffffff81018db4>] native_nmi_stop_other_cpus+0x8a/0xd6 [<ffffffff810188ba>] native_machine_shutdown+0x50/0x67 [<ffffffff81018926>] machine_shutdown+0xa/0xc [<ffffffff8101897e>] native_machine_restart+0x20/0x32 [<ffffffff810189b0>] machine_restart+0xa/0xc [<ffffffff8103b196>] kernel_restart+0x47/0x4c [<ffffffff8103b2e6>] sys_reboot+0x13e/0x17c [<ffffffff8164e436>] ? _raw_spin_unlock_bh+0x10/0x12 [<ffffffff810fcac9>] ? bdi_queue_work+0xcf/0xd8 [<ffffffff810fe82f>] ? __bdi_start_writeback+0xae/0xb7 [<ffffffff810e0d64>] ? iterate_supers+0xa3/0xb7 [<ffffffff816547a2>] system_call_fastpath+0x16/0x1b ---[ end trace 320af5cb1cb60c5b ]--- The root cause seems to be the default_send_IPI_mask_allbutself_phys() takes quite some time (I measured it could be several ms) to complete sending NMIs to all the other 23 CPUs, and for HZ=250/1000 system, the time is long enough for a timer interrupt to happen, which will in turn trigger to kick load balance to a stopped CPU and cause this warning in native_smp_send_reschedule(). So disabling the local irq before stop_other_cpu() can fix this problem (tested 25 times reboot ok), and it is fine as there should be nobody caring the timer interrupt in such reboot stage. The latest 3.4 kernel slightly changes this behavior by sending REBOOT_VECTOR first and only send NMI_VECTOR if the REBOOT_VCTOR fails, and this patch is still needed to prevent the problem. Signed-off-by: Feng Tang <feng.tang@intel.com> Acked-by: Don Zickus <dzickus@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20120530231541.4c13433a@feng-i7 Signed-off-by: Ingo Molnar <mingo@kernel.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Vinson Lee <vlee@twopensource.com>
* config: Enable NEED_DMA_MAP_STATE by default when SWIOTLB is selectedKonrad Rzeszutek Wilk2015-08-071-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit a6dfa128ce5c414ab46b1d690f7a1b8decb8526d upstream. A huge amount of NIC drivers use the DMA API, however if compiled under 32-bit an very important part of the DMA API can be ommitted leading to the drivers not working at all (especially if used with 'swiotlb=force iommu=soft'). As Prashant Sreedharan explains it: "the driver [tg3] uses DEFINE_DMA_UNMAP_ADDR(), dma_unmap_addr_set() to keep a copy of the dma "mapping" and dma_unmap_addr() to get the "mapping" value. On most of the platforms this is a no-op, but ... with "iommu=soft and swiotlb=force" this house keeping is required, ... otherwise we pass 0 while calling pci_unmap_/pci_dma_sync_ instead of the DMA address." As such enable this even when using 32-bit kernels. Reported-by: Ian Jackson <Ian.Jackson@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Prashant Sreedharan <prashant@broadcom.com> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Chan <mchan@broadcom.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: boris.ostrovsky@oracle.com Cc: cascardo@linux.vnet.ibm.com Cc: david.vrabel@citrix.com Cc: sanjeevb@broadcom.com Cc: siva.kallam@broadcom.com Cc: vyasevich@gmail.com Cc: xen-devel@lists.xensource.com Link: http://lkml.kernel.org/r/20150417190448.GA9462@l.oracle.com Signed-off-by: Ingo Molnar <mingo@kernel.org> [bwh: Backported to 3.2: also change the def_bool (cond) to def_bool y + depends] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86_64: Fix strnlen_user() to not touch memory after specified maximumBen Hutchings2015-08-071-1/+1
| | | | | | | | | | Inspired by commit f18c34e483ff ("lib: Fix strnlen_user() to not touch memory after specified maximum") upstream. This version of strnlen_user(), no longer present upstream, has a similar off-by-one error. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Jan Kara <jack@suse.cz>
* x86: bpf_jit: fix compilation of large bpf programsAlexei Starovoitov2015-08-071-1/+6
| | | | | | | | | | | | | | | | | | | | | | | commit 3f7352bf21f8fd7ba3e2fcef9488756f188e12be upstream. x86 has variable length encoding. x86 JIT compiler is trying to pick the shortest encoding for given bpf instruction. While doing so the jump targets are changing, so JIT is doing multiple passes over the program. Typical program needs 3 passes. Some very short programs converge with 2 passes. Large programs may need 4 or 5. But specially crafted bpf programs may hit the pass limit and if the program converges on the last iteration the JIT compiler will be producing an image full of 'int 3' insns. Fix this corner case by doing final iteration over bpf program. Fixes: 0a14842f5a3c ("net: filter: Just In Time compiler for x86-64") Reported-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Tested-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* KVM: MMU: fix CR4.SMEP=1, CR0.WP=0 with shadow pagesPaolo Bonzini2015-08-071-1/+1
| | | | | | | | | | | | | commit 898761158be7682082955e3efa4ad24725305fc7 upstream. smep_andnot_wp is initialized in kvm_init_shadow_mmu and shadow pages should not be reused for different values of it. Thus, it has to be added to the mask in kvm_mmu_pte_write. Reviewed-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* KVM: VMX: Preserve host CR4.MCE value while in guest mode.Ben Serebrin2015-08-071-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | commit 085e68eeafbf76e21848ad5bafaecec88a11dd64 upstream. The host's decision to enable machine check exceptions should remain in force during non-root mode. KVM was writing 0 to cr4 on VCPU reset and passed a slightly-modified 0 to the vmcs.guest_cr4 value. Tested: Built. On earlier version, tested by injecting machine check while a guest is spinning. Before the change, if guest CR4.MCE==0, then the machine check is escalated to Catastrophic Error (CATERR) and the machine dies. If guest CR4.MCE==1, then the machine check causes VMEXIT and is handled normally by host Linux. After the change, injecting a machine check causes normal Linux machine check handling. Signed-off-by: Ben Serebrin <serebrin@google.com> Reviewed-by: Venkatesh Srinivas <venkateshs@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.2: use read_cr4() instead of cr4_read_shadow()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/iommu: Fix header comments regarding standard and _FINISH macrosAravind Gopalakrishnan2015-08-071-5/+6
| | | | | | | | | | | | | | | | | | | | | | | | | commit b44915927ca88084a7292e4ddd4cf91036f365e1 upstream. The comment line regarding IOMMU_INIT and IOMMU_INIT_FINISH macros is incorrect: "The standard vs the _FINISH differs in that the _FINISH variant will continue detecting other IOMMUs in the call list..." It should be "..the *standard* variant will continue detecting..." Fix that. Also, make it readable while at it. Signed-off-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: konrad.wilk@oracle.com Fixes: 6e9636693373 ("x86, iommu: Update header comments with appropriate naming") Link: http://lkml.kernel.org/r/1428508017-5316-1-git-send-email-Aravind.Gopalakrishnan@amd.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/reboot: Add ASRock Q1900DC-ITX mainboard reboot quirkStefan Lippers-Hollmann2015-05-091-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 80313b3078fcd2ca51970880d90757f05879a193 upstream. The ASRock Q1900DC-ITX mainboard (Baytrail-D) hangs randomly in both BIOS and UEFI mode while rebooting unless reboot=pci is used. Add a quirk to reboot via the pci method. The problem is very intermittent and hard to debug, it might succeed rebooting just fine 40 times in a row - but fails half a dozen times the next day. It seems to be slightly less common in BIOS CSM mode than native UEFI (with the CSM disabled), but it does happen in either mode. Since I've started testing this patch in late january, rebooting has been 100% reliable. Most of the time it already hangs during POST, but occasionally it might even make it through the bootloader and the kernel might even start booting, but then hangs before the mode switch. The same symptoms occur with grub-efi, gummiboot and grub-pc, just as well as (at least) kernel 3.16-3.19 and 4.0-rc6 (I haven't tried older kernels than 3.16). Upgrading to the most current mainboard firmware of the ASRock Q1900DC-ITX, version 1.20, does not improve the situation. ( Searching the web seems to suggest that other Bay Trail-D mainboards might be affected as well. ) -- Signed-off-by: Stefan Lippers-Hollmann <s.l-h@gmx.de> Cc: Matt Fleming <matt.fleming@intel.com> Link: http://lkml.kernel.org/r/20150330224427.0fb58e42@mir Signed-off-by: Ingo Molnar <mingo@kernel.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/reboot: Add reboot quirk for Certec BPC600Christian Gmeiner2015-05-091-0/+9
| | | | | | | | | | | | | | | | | | commit aadca6fa4068ad1f92c492bc8507b7ed350825a2 upstream. Certec BPC600 needs reboot=pci to actually reboot. Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Li Aubrey <aubrey.li@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Dave Jones <davej@redhat.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1399446114-2147-1-git-send-email-christian.gmeiner@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/reboot: Add reboot quirk for Dell Latitude E5410Ville Syrjälä2015-05-091-0/+8
| | | | | | | | | | | commit 8412da757776727796e9edd64ba94814cc08d536 upstream. Dell Latitude E5410 needs reboot=pci to actually reboot. Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: http://lkml.kernel.org/r/1380888964-14517-1-git-send-email-ville.syrjala@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/reboot: Remove the duplicate C6100 entry in the reboot quirks listMasoud Sharbiani2015-05-091-8/+0
| | | | | | | | | | | | | | | | | commit b5eafc6f07c95e9f3dd047e72737449cb03c9956 upstream. Two entries for the same system type were added, with two different vendor names: 'Dell' and 'Dell, Inc.'. Since a prefix match is being used by the DMI parsing code, we can eliminate the latter as redundant. Reported-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Masoud Sharbiani <msharbiani@twitter.com> Cc: holt@sgi.com Link: http://lkml.kernel.org/r/1380216643-4683-1-git-send-email-masoud.sharbiani@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/reboot: Fix apparent cut-n-paste mistake in Dell reboot workaroundDave Jones2015-05-091-1/+1
| | | | | | | | | | | | commit 7a20c2fad61aa3624e83c671d36dbd36b2661476 upstream. This seems to have been copied from the Optiplex 990 entry above, but somoene forgot to change the ident text. Signed-off-by: Dave Jones <davej@fedoraproject.org> Link: http://lkml.kernel.org/r/20130925001344.GA13554@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/reboot: Add quirk to make Dell C6100 use reboot=pci automaticallyMasoud Sharbiani2015-05-091-0/+16
| | | | | | | | | | | | | | | commit 4f0acd31c31f03ba42494c8baf6c0465150e2621 upstream. Dell PowerEdge C6100 machines fail to completely reboot about 20% of the time. Signed-off-by: Masoud Sharbiani <msharbiani@twitter.com> Signed-off-by: Vinson Lee <vlee@twitter.com> Cc: Robin Holt <holt@sgi.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Guan Xuetao <gxt@mprc.pku.edu.cn> Link: http://lkml.kernel.org/r/1379717947-18042-1-git-send-email-vlee@freedesktop.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/reboot: Remove quirk entry for SBC FITPCDavid Hooper2015-05-091-8/+0
| | | | | | | | | | | | | | | | | commit fcd8af585f587741c051f7124b8dee6c73c8629b upstream. Remove the quirk for the SBC FITPC. It seems ot have been required when the default was kbd reboot, but no longer required now that the default is acpi reboot. Furthermore, BIOS reboot no longer works for this board as of 2.6.39 or any of the 3.x kernels. Signed-off-by: David Hooper <dave@beermex.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Link: http://lkml.kernel.org/r/20121002142635.17403.59959.stgit@localhost.localdomain Signed-off-by: Ingo Molnar <mingo@kernel.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ACPI, x86: fix Dell M6600 ACPI reboot regression via DMIZhang Rui2015-05-091-0/+8
| | | | | | | | | | | | | | commit 76eb9a30db4bc8fd172f9155247264b5f2686d7b upstream. Dell Precision M6600 is known to require PCI reboot, so add it to the reboot blacklist in pci_reboot_dmi_table[]. https://bugzilla.kernel.org/show_bug.cgi?id=42749 cc: x86@kernel.org Signed-off-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/reboot: Remove VersaLogic Menlow reboot quirkMichael D Labriola2015-05-091-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit e6d36a653becc7bbc643c399a77882e02bf552cb upstream. This commit removes the reboot quirk originally added by commit e19e074 ("x86: Fix reboot problem on VersaLogic Menlow boards"). Testing with a VersaLogic Ocelot (VL-EPMs-21a rev 1.00 w/ BIOS 6.5.102) revealed the following regarding the reboot hang problem: - v2.6.37 reboot=bios was needed. - v2.6.38-rc1: behavior changed, reboot=acpi is needed, reboot=kbd and reboot=bios results in system hang. - v2.6.38: VersaLogic patch (e19e074 "x86: Fix reboot problem on VersaLogic Menlow boards") was applied prior to v2.6.38-rc7. This patch sets a quirk for VersaLogic Menlow boards that forces the use of reboot=bios, which doesn't work anymore. - v3.2: It seems that commit 660e34c ("x86: Reorder reboot method preferences") changed the default reboot method to acpi prior to v3.0-rc1, which means the default behavior is appropriate for the Ocelot. No VersaLogic quirk is required. The Ocelot board used for testing can successfully reboot w/out having to pass any reboot= arguments for all 3 current versions of the BIOS. Signed-off-by: Michael D Labriola <michael.d.labriola@gmail.com> Cc: Matthew Garrett <mjg@redhat.com> Cc: Michael D Labriola <mlabriol@gdeb.com> Cc: Kushal Koolwal <kushalkoolwal@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/87vcnub9hu.fsf@gmail.com Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* crypto: aesni - fix memory usage in GCM decryptionStephan Mueller2015-05-091-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit ccfe8c3f7e52ae83155cb038753f4c75b774ca8a upstream. The kernel crypto API logic requires the caller to provide the length of (ciphertext || authentication tag) as cryptlen for the AEAD decryption operation. Thus, the cipher implementation must calculate the size of the plaintext output itself and cannot simply use cryptlen. The RFC4106 GCM decryption operation tries to overwrite cryptlen memory in req->dst. As the destination buffer for decryption only needs to hold the plaintext memory but cryptlen references the input buffer holding (ciphertext || authentication tag), the assumption of the destination buffer length in RFC4106 GCM operation leads to a too large size. This patch simply uses the already calculated plaintext size. In addition, this patch fixes the offset calculation of the AAD buffer pointer: as mentioned before, cryptlen already includes the size of the tag. Thus, the tag does not need to be added. With the addition, the AAD will be written beyond the already allocated buffer. Note, this fixes a kernel crash that can be triggered from user space via AF_ALG(aead) -- simply use the libkcapi test application from [1] and update it to use rfc4106-gcm-aes. Using [1], the changes were tested using CAVS vectors to demonstrate that the crypto operation still delivers the right results. [1] http://www.chronox.de/libkcapi.html CC: Tadeusz Struk <tadeusz.struk@intel.com> Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/asm/entry/32: Fix user_mode() misusesAndy Lutomirski2015-05-091-1/+1
| | | | | | | | | | | | | | | | | commit 394838c96013ba414a24ffe7a2a593a9154daadf upstream. The one in do_debug() is probably harmless, but better safe than sorry. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/d67deaa9df5458363623001f252d1aee3215d014.1425948056.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org> [bwh: Backported to 3.2: drop the do_bounds() part] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/vdso: Fix the build on GCC5Jiri Slaby2015-05-091-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit e893286918d2cde3a94850d8f7101cd1039e0c62 upstream. On gcc5 the kernel does not link: ld: .eh_frame_hdr table[4] FDE at 0000000000000648 overlaps table[5] FDE at 0000000000000670. Because prior GCC versions always emitted NOPs on ALIGN directives, but gcc5 started omitting them. .LSTARTFDEDLSI1 says: /* HACK: The dwarf2 unwind routines will subtract 1 from the return address to get an address in the middle of the presumed call instruction. Since we didn't get here via a call, we need to include the nop before the real start to make up for it. */ .long .LSTART_sigreturn-1-. /* PC-relative start address */ But commit 69d0627a7f6e ("x86 vDSO: reorder vdso32 code") from 2.6.25 replaced .org __kernel_vsyscall+32,0x90 by ALIGN right before __kernel_sigreturn. Of course, ALIGN need not generate any NOP in there. Esp. gcc5 collapses vclock_gettime.o and int80.o together with no generated NOPs as "ALIGN". So fix this by adding to that point at least a single NOP and make the function ALIGN possibly with more NOPs then. Kudos for reporting and diagnosing should go to Richard. Reported-by: Richard Biener <rguenther@suse.de> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1425543211-12542-1-git-send-email-jslaby@suse.cz Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/asm/entry/64: Remove a bogus 'ret_from_fork' optimizationAndy Lutomirski2015-05-091-5/+8
| | | | | | | | | | | | | | | | | | | | | | | | | commit 956421fbb74c3a6261903f3836c0740187cf038b upstream. 'ret_from_fork' checks TIF_IA32 to determine whether 'pt_regs' and the related state make sense for 'ret_from_sys_call'. This is entirely the wrong check. TS_COMPAT would make a little more sense, but there's really no point in keeping this optimization at all. This fixes a return to the wrong user CS if we came from int 0x80 in a 64-bit task. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/4710be56d76ef994ddf59087aad98c000fbab9a4.1424989793.git.luto@amacapital.net [ Backported from tip:x86/asm. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* KVM: emulate: fix CMPXCHG8B on 32-bit hostsPaolo Bonzini2015-05-091-1/+2
| | | | | | | | | | | | | | | | | | | | | commit 4ff6f8e61eb7f96d3ca535c6d240f863ccd6fb7d upstream. This has been broken for a long time: it broke first in 2.6.35, then was almost fixed in 2.6.36 but this one-liner slipped through the cracks. The bug shows up as an infinite loop in Windows 7 (and newer) boot on 32-bit hosts without EPT. Windows uses CMPXCHG8B to write to page tables, which causes a page fault if running without EPT; the emulator is then called from kvm_mmu_page_fault. The loop then happens if the higher 4 bytes are not 0; the common case for this is that the NX bit (bit 63) is 1. Fixes: 6550e1f165f384f3a46b60a1be9aba4bc3c2adad Fixes: 16518d5ada690643453eb0aef3cc7841d3623c2d Reported-by: Erik Rull <erik.rull@rdsoftware.de> Tested-by: Erik Rull <erik.rull@rdsoftware.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86, mm/ASLR: Fix stack randomization on 64-bit systemsHector Marco-Gisbert2015-05-091-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 4e7c22d447bb6d7e37bfe39ff658486ae78e8d77 upstream. The issue is that the stack for processes is not properly randomized on 64 bit architectures due to an integer overflow. The affected function is randomize_stack_top() in file "fs/binfmt_elf.c": static unsigned long randomize_stack_top(unsigned long stack_top) { unsigned int random_variable = 0; if ((current->flags & PF_RANDOMIZE) && !(current->personality & ADDR_NO_RANDOMIZE)) { random_variable = get_random_int() & STACK_RND_MASK; random_variable <<= PAGE_SHIFT; } return PAGE_ALIGN(stack_top) + random_variable; return PAGE_ALIGN(stack_top) - random_variable; } Note that, it declares the "random_variable" variable as "unsigned int". Since the result of the shifting operation between STACK_RND_MASK (which is 0x3fffff on x86_64, 22 bits) and PAGE_SHIFT (which is 12 on x86_64): random_variable <<= PAGE_SHIFT; then the two leftmost bits are dropped when storing the result in the "random_variable". This variable shall be at least 34 bits long to hold the (22+12) result. These two dropped bits have an impact on the entropy of process stack. Concretely, the total stack entropy is reduced by four: from 2^28 to 2^30 (One fourth of expected entropy). This patch restores back the entropy by correcting the types involved in the operations in the functions randomize_stack_top() and stack_maxrandom_size(). The successful fix can be tested with: $ for i in `seq 1 10`; do cat /proc/self/maps | grep stack; done 7ffeda566000-7ffeda587000 rw-p 00000000 00:00 0 [stack] 7fff5a332000-7fff5a353000 rw-p 00000000 00:00 0 [stack] 7ffcdb7a1000-7ffcdb7c2000 rw-p 00000000 00:00 0 [stack] 7ffd5e2c4000-7ffd5e2e5000 rw-p 00000000 00:00 0 [stack] ... Once corrected, the leading bytes should be between 7ffc and 7fff, rather than always being 7fff. Signed-off-by: Hector Marco-Gisbert <hecmargi@upv.es> Signed-off-by: Ismael Ripoll <iripoll@upv.es> [ Rebased, fixed 80 char bugs, cleaned up commit message, added test example and CVE ] Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Fixes: CVE-2015-1593 Link: http://lkml.kernel.org/r/20150214173350.GA18393@www.outflux.net Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86: mm/fault: Fix semaphore imbalanceBen Hutchings2015-03-061-1/+1
| | | | | | | | | | | When backporting commit 33692f27597f ('vm: add VM_FAULT_SIGSEGV handling support') I didn't notice that it depended on a recent change to the locking context of mm_fault_error() (commit 7fb08eca4527, 'x86: mm: move mmap_sem unlock from mm_fault_error() to caller'). That isn't easily applicable to 3.2, so instead make sure we drop mm->mmap_sem on the new branch of mm_fault_error(). Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* KVM: x86: SYSENTER emulation is brokenNadav Amit2015-02-201-17/+8
| | | | | | | | | | | | | | | | | | | | commit f3747379accba8e95d70cec0eae0582c8c182050 upstream. SYSENTER emulation is broken in several ways: 1. It misses the case of 16-bit code segments completely (CVE-2015-0239). 2. MSR_IA32_SYSENTER_CS is checked in 64-bit mode incorrectly (bits 0 and 1 can still be set without causing #GP). 3. MSR_IA32_SYSENTER_EIP and MSR_IA32_SYSENTER_ESP are not masked in legacy-mode. 4. There is some unneeded code. Fix it. Cc: stable@vger.linux.org Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* KVM: x86 emulator: reject SYSENTER in compatibility mode on AMD guestsAvi Kivity2015-02-201-0/+19
| | | | | | | | | | | | commit 1a18a69b762374c423305772500f36eb8984ca52 upstream. If the guest thinks it's an AMD, it will not have prepared the SYSENTER MSRs, and if the guest executes SYSENTER in compatibility mode, it will fails. Detect this condition and #UD instead, like the spec says. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86, cpu, amd: Add workaround for family 16h, erratum 793Borislav Petkov2015-02-202-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3b56496865f9f7d9bcb2f93b44c63f274f08e3b6 upstream. This adds the workaround for erratum 793 as a precaution in case not every BIOS implements it. This addresses CVE-2013-6885. Erratum text: [Revision Guide for AMD Family 16h Models 00h-0Fh Processors, document 51810 Rev. 3.04 November 2013] 793 Specific Combination of Writes to Write Combined Memory Types and Locked Instructions May Cause Core Hang Description Under a highly specific and detailed set of internal timing conditions, a locked instruction may trigger a timing sequence whereby the write to a write combined memory type is not flushed, causing the locked instruction to stall indefinitely. Potential Effect on System Processor core hang. Suggested Workaround BIOS should set MSR C001_1020[15] = 1b. Fix Planned No fix planned [ hpa: updated description, fixed typo in MSR name ] Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/20140114230711.GS29865@pd.tnic Tested-by: Aravind Gopalakrishnan <aravind.gopalakrishnan@amd.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> [bwh: Backported to 3.2: - Adjust filename - Venkatesh Srinivas pointed out we should use {rd,wr}msrl_safe() to avoid crashing on KVM. This was fixed upstream by commit 8f86a7373a1c ("x86, AMD: Convert to the new bit access MSR accessors") but that's too much trouble to backport. Here we must use {rd,wr}msrl_amd_safe().] Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Moritz Muehlenhoff <jmm@debian.org> Cc: Venkatesh Srinivas <venkateshs@google.com>
* Revert "x86, 64bit, mm: Mark data/bss/brk to nx"Ben Hutchings2015-02-201-4/+3
| | | | | | | | | | | This reverts commit e105c8187b7101e8a8a54ac0218c9d9c9463c636 which was commit 72212675d1c96f5db8ec6fb35701879911193158 upstream. This caused suspend/resume to stop working on at least some systems - specifically, the system would reboot when woken. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org>
* Revert "x86, mm: Set NX across entire PMD at boot"Ben Hutchings2015-02-201-10/+1
| | | | | | | | | | | This reverts commit a5c187d92d2ce30315f333b9dff33af832e8b443 which was commit 45e2a9d4701d8c624d4a4bcdd1084eae31e92f58 upstream. The previous commit caused suspend/resume to stop working on at least some systems - specifically, the system would reboot when woken. Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org>
* vm: add VM_FAULT_SIGSEGV handling supportLinus Torvalds2015-02-201-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 33692f27597fcab536d7cbbcc8f52905133e4aa7 upstream. The core VM already knows about VM_FAULT_SIGBUS, but cannot return a "you should SIGSEGV" error, because the SIGSEGV case was generally handled by the caller - usually the architecture fault handler. That results in lots of duplication - all the architecture fault handlers end up doing very similar "look up vma, check permissions, do retries etc" - but it generally works. However, there are cases where the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV. In particular, when accessing the stack guard page, libsigsegv expects a SIGSEGV. And it usually got one, because the stack growth is handled by that duplicated architecture fault handler. However, when the generic VM layer started propagating the error return from the stack expansion in commit fee7e49d4514 ("mm: propagate error from stack expansion even for guard page"), that now exposed the existing VM_FAULT_SIGBUS result to user space. And user space really expected SIGSEGV, not SIGBUS. To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those duplicate architecture fault handlers about it. They all already have the code to handle SIGSEGV, so it's about just tying that new return value to the existing code, but it's all a bit annoying. This is the mindless minimal patch to do this. A more extensive patch would be to try to gather up the mostly shared fault handling logic into one generic helper routine, and long-term we really should do that cleanup. Just from this patch, you can generally see that most architectures just copied (directly or indirectly) the old x86 way of doing things, but in the meantime that original x86 model has been improved to hold the VM semaphore for shorter times etc and to handle VM_FAULT_RETRY and other "newer" things, so it would be a good idea to bring all those improvements to the generic case and teach other architectures about them too. Reported-and-tested-by: Takashi Iwai <tiwai@suse.de> Tested-by: Jan Engelhardt <jengelh@inai.de> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots" Cc: linux-arch@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [bwh: Backported to 3.2: - Adjust filenames, context - Drop arc, metag, nios2 and lustre changes - For sh, patch both 32-bit and 64-bit implementations to use goto bad_area - For s390, pass int_code and trans_exc_code as arguments to do_no_context() and do_sigsegv()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86, tls: Interpret an all-zero struct user_desc as "no segment"Andy Lutomirski2015-02-202-2/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3669ef9fa7d35f573ec9c0e0341b29251c2734a7 upstream. The Witcher 2 did something like this to allocate a TLS segment index: struct user_desc u_info; bzero(&u_info, sizeof(u_info)); u_info.entry_number = (uint32_t)-1; syscall(SYS_set_thread_area, &u_info); Strictly speaking, this code was never correct. It should have set read_exec_only and seg_not_present to 1 to indicate that it wanted to find a free slot without putting anything there, or it should have put something sensible in the TLS slot if it wanted to allocate a TLS entry for real. The actual effect of this code was to allocate a bogus segment that could be used to exploit espfix. The set_thread_area hardening patches changed the behavior, causing set_thread_area to return -EINVAL and crashing the game. This changes set_thread_area to interpret this as a request to find a free slot and to leave it empty, which isn't *quite* what the game expects but should be close enough to keep it working. In particular, using the code above to allocate two segments will allocate the same segment both times. According to FrostbittenKing on Github, this fixes The Witcher 2. If this somehow still causes problems, we could instead allocate a limit==0 32-bit data segment, but that seems rather ugly to me. Fixes: 41bdc78544b8 x86/tls: Validate TLS entries to protect espfix Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: torvalds@linux-foundation.org Link: http://lkml.kernel.org/r/0cb251abe1ff0958b8e468a9a9a905b80ae3a746.1421954363.git.luto@amacapital.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86, tls, ldt: Stop checking lm in LDT_emptyAndy Lutomirski2015-02-201-7/+2
| | | | | | | | | | | | | | | | | | commit e30ab185c490e9a9381385529e0fd32f0a399495 upstream. 32-bit programs don't have an lm bit in their ABI, so they can't reliably cause LDT_empty to return true without resorting to memset. They shouldn't need to do this. This should fix a longstanding, if minor, issue in all 64-bit kernels as well as a potential regression in the TLS hardening code. Fixes: 41bdc78544b8 x86/tls: Validate TLS entries to protect espfix Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: torvalds@linux-foundation.org Link: http://lkml.kernel.org/r/72a059de55e86ad5e2935c80aa91880ddf19d07c.1421954363.git.luto@amacapital.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86, hyperv: Mark the Hyper-V clocksource as being continuousK. Y. Srinivasan2015-02-201-0/+1
| | | | | | | | | | | | | | | | commit 32c6590d126836a062b3140ed52d898507987017 upstream. The Hyper-V clocksource is continuous; mark it accordingly. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Acked-by: jasowang@redhat.com Cc: gregkh@linuxfoundation.org Cc: devel@linuxdriverproject.org Cc: olaf@aepfle.de Cc: apw@canonical.com Link: http://lkml.kernel.org/r/1421108762-3331-1-git-send-email-kys@microsoft.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* ftrace/jprobes/x86: Fix conflict between jprobes and function graph tracingSteven Rostedt (Red Hat)2015-02-201-5/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 237d28db036e411f22c03cfd5b0f6dc2aa9bf3bc upstream. If the function graph tracer traces a jprobe callback, the system will crash. This can easily be demonstrated by compiling the jprobe sample module that is in the kernel tree, loading it and running the function graph tracer. # modprobe jprobe_example.ko # echo function_graph > /sys/kernel/debug/tracing/current_tracer # ls The first two commands end up in a nice crash after the first fork. (do_fork has a jprobe attached to it, so "ls" just triggers that fork) The problem is caused by the jprobe_return() that all jprobe callbacks must end with. The way jprobes works is that the function a jprobe is attached to has a breakpoint placed at the start of it (or it uses ftrace if fentry is supported). The breakpoint handler (or ftrace callback) will copy the stack frame and change the ip address to return to the jprobe handler instead of the function. The jprobe handler must end with jprobe_return() which swaps the stack and does an int3 (breakpoint). This breakpoint handler will then put back the saved stack frame, simulate the instruction at the beginning of the function it added a breakpoint to, and then continue on. For function tracing to work, it hijakes the return address from the stack frame, and replaces it with a hook function that will trace the end of the call. This hook function will restore the return address of the function call. If the function tracer traces the jprobe handler, the hook function for that handler will not be called, and its saved return address will be used for the next function. This will result in a kernel crash. To solve this, pause function tracing before the jprobe handler is called and unpause it before it returns back to the function it probed. Some other updates: Used a variable "saved_sp" to hold kcb->jprobe_saved_sp. This makes the code look a bit cleaner and easier to understand (various tries to fix this bug required this change). Note, if fentry is being used, jprobes will change the ip address before the function graph tracer runs and it will not be able to trace the function that the jprobe is probing. Link: http://lkml.kernel.org/r/20150114154329.552437962@goodmis.org Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> [bwh: Backported to 3.2: adjust filename, context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* crypto: include crypto- module prefix in templateKees Cook2015-02-201-0/+3
| | | | | | | | | | | | | | | | | | | | | | | commit 4943ba16bbc2db05115707b3ff7b4874e9e3c560 upstream. This adds the module loading prefix "crypto-" to the template lookup as well. For example, attempting to load 'vfat(blowfish)' via AF_ALG now correctly includes the "crypto-" prefix at every level, correctly rejecting "vfat": net-pf-38 algif-hash crypto-vfat(blowfish) crypto-vfat(blowfish)-all crypto-vfat Reported-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> [bwh: Backported to 3.2: drop changes to cmac and mcryptd which we don't have] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* crypto: prefix module autoloading with "crypto-"Kees Cook2015-02-209-15/+15
| | | | | | | | | | | | | | | | | | commit 5d26a105b5a73e5635eae0629b42fa0a90e07b7b upstream. This prefixes all crypto module loading with "crypto-" so we never run the risk of exposing module auto-loading to userspace via a crypto API, as demonstrated by Mathias Krause: https://lkml.org/lkml/2013/3/4/70 Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> [bwh: Backported to 3.2: - Adjust filenames - Drop changes to algorithms and drivers we don't have - Add aliases to generic C implementations that didn't need them before] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86_64, vdso: Fix the vdso address randomization algorithmAndy Lutomirski2015-02-201-14/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 394f56fe480140877304d342dec46d50dc823d46 upstream. The theory behind vdso randomization is that it's mapped at a random offset above the top of the stack. To avoid wasting a page of memory for an extra page table, the vdso isn't supposed to extend past the lowest PMD into which it can fit. Other than that, the address should be a uniformly distributed address that meets all of the alignment requirements. The current algorithm is buggy: the vdso has about a 50% probability of being at the very end of a PMD. The current algorithm also has a decent chance of failing outright due to incorrect handling of the case where the top of the stack is near the top of its PMD. This fixes the implementation. The paxtest estimate of vdso "randomisation" improves from 11 bits to 18 bits. (Disclaimer: I don't know what the paxtest code is actually calculating.) It's worth noting that this algorithm is inherently biased: the vdso is more likely to end up near the end of its PMD than near the beginning. Ideally we would either nix the PMD sharing requirement or jointly randomize the vdso and the stack to reduce the bias. In the mean time, this is a considerable improvement with basically no risk of compatibility issues, since the allowed outputs of the algorithm are unchanged. As an easy test, doing this: for i in `seq 10000` do grep -P vdso /proc/self/maps |cut -d- -f1 done |sort |uniq -d used to produce lots of output (1445 lines on my most recent run). A tiny subset looks like this: 7fffdfffe000 7fffe01fe000 7fffe05fe000 7fffe07fe000 7fffe09fe000 7fffe0bfe000 7fffe0dfe000 Note the suspicious fe000 endings. With the fix, I get a much more palatable 76 repeated addresses. Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andy Lutomirski <luto@amacapital.net> [bwh: Backported to 3.2: - Adjust context - The whole file is only built for x86_64; adjust comment for this] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/tls: Don't validate lm in set_thread_area() after allAndy Lutomirski2015-02-202-6/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 3fb2f4237bb452eb4e98f6a5dbd5a445b4fed9d0 upstream. It turns out that there's a lurking ABI issue. GCC, when compiling this in a 32-bit program: struct user_desc desc = { .entry_number = idx, .base_addr = base, .limit = 0xfffff, .seg_32bit = 1, .contents = 0, /* Data, grow-up */ .read_exec_only = 0, .limit_in_pages = 1, .seg_not_present = 0, .useable = 0, }; will leave .lm uninitialized. This means that anything in the kernel that reads user_desc.lm for 32-bit tasks is unreliable. Revert the .lm check in set_thread_area(). The value never did anything in the first place. Fixes: 0e58af4e1d21 ("x86/tls: Disallow unusual TLS segments") Signed-off-by: Andy Lutomirski <luto@amacapital.net> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/d7875b60e28c512f6a6fc0baf5714d58e7eaadbb.1418856405.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org> [bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86/tls: Disallow unusual TLS segmentsAndy Lutomirski2015-02-201-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit 0e58af4e1d2166e9e33375a0f121e4867010d4f8 upstream. Users have no business installing custom code segments into the GDT, and segments that are not present but are otherwise valid are a historical source of interesting attacks. For completeness, block attempts to set the L bit. (Prior to this patch, the L bit would have been silently dropped.) This is an ABI break. I've checked glibc, musl, and Wine, and none of them look like they'll have any trouble. Note to stable maintainers: this is a hardening patch that fixes no known bugs. Given the possibility of ABI issues, this probably shouldn't be backported quickly. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Acked-by: H. Peter Anvin <hpa@zytor.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: security@kernel.org <security@kernel.org> Cc: Willy Tarreau <w@1wt.eu> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86_64, switch_to(): Load TLS descriptors before switching DS and ESAndy Lutomirski2015-02-201-28/+73
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit f647d7c155f069c1a068030255c300663516420e upstream. Otherwise, if buggy user code points DS or ES into the TLS array, they would be corrupted after a context switch. This also significantly improves the comments and documents some gotchas in the code. Before this patch, the both tests below failed. With this patch, the es test passes, although the gsbase test still fails. ----- begin es test ----- /* * Copyright (c) 2014 Andy Lutomirski * GPL v2 */ static unsigned short GDT3(int idx) { return (idx << 3) | 3; } static int create_tls(int idx, unsigned int base) { struct user_desc desc = { .entry_number = idx, .base_addr = base, .limit = 0xfffff, .seg_32bit = 1, .contents = 0, /* Data, grow-up */ .read_exec_only = 0, .limit_in_pages = 1, .seg_not_present = 0, .useable = 0, }; if (syscall(SYS_set_thread_area, &desc) != 0) err(1, "set_thread_area"); return desc.entry_number; } int main() { int idx = create_tls(-1, 0); printf("Allocated GDT index %d\n", idx); unsigned short orig_es; asm volatile ("mov %%es,%0" : "=rm" (orig_es)); int errors = 0; int total = 1000; for (int i = 0; i < total; i++) { asm volatile ("mov %0,%%es" : : "rm" (GDT3(idx))); usleep(100); unsigned short es; asm volatile ("mov %%es,%0" : "=rm" (es)); asm volatile ("mov %0,%%es" : : "rm" (orig_es)); if (es != GDT3(idx)) { if (errors == 0) printf("[FAIL]\tES changed from 0x%hx to 0x%hx\n", GDT3(idx), es); errors++; } } if (errors) { printf("[FAIL]\tES was corrupted %d/%d times\n", errors, total); return 1; } else { printf("[OK]\tES was preserved\n"); return 0; } } ----- end es test ----- ----- begin gsbase test ----- /* * gsbase.c, a gsbase test * Copyright (c) 2014 Andy Lutomirski * GPL v2 */ static unsigned char *testptr, *testptr2; static unsigned char read_gs_testvals(void) { unsigned char ret; asm volatile ("movb %%gs:%1, %0" : "=r" (ret) : "m" (*testptr)); return ret; } int main() { int errors = 0; testptr = mmap((void *)0x200000000UL, 1, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_FIXED | MAP_ANONYMOUS, -1, 0); if (testptr == MAP_FAILED) err(1, "mmap"); testptr2 = mmap((void *)0x300000000UL, 1, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_FIXED | MAP_ANONYMOUS, -1, 0); if (testptr2 == MAP_FAILED) err(1, "mmap"); *testptr = 0; *testptr2 = 1; if (syscall(SYS_arch_prctl, ARCH_SET_GS, (unsigned long)testptr2 - (unsigned long)testptr) != 0) err(1, "ARCH_SET_GS"); usleep(100); if (read_gs_testvals() == 1) { printf("[OK]\tARCH_SET_GS worked\n"); } else { printf("[FAIL]\tARCH_SET_GS failed\n"); errors++; } asm volatile ("mov %0,%%gs" : : "r" (0)); if (read_gs_testvals() == 0) { printf("[OK]\tWriting 0 to gs worked\n"); } else { printf("[FAIL]\tWriting 0 to gs failed\n"); errors++; } usleep(100); if (read_gs_testvals() == 0) { printf("[OK]\tgsbase is still zero\n"); } else { printf("[FAIL]\tgsbase was corrupted\n"); errors++; } return errors == 0 ? 0 : 1; } ----- end gsbase test ----- Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Andi Kleen <andi@firstfloor.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/509d27c9fec78217691c3dad91cec87e1006b34a.1418075657.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* x86: kvm: use alternatives for VMCALL vs. VMMCALL if kernel text is read-onlyPaolo Bonzini2015-01-013-2/+16
| | | | | | | | | | | | | | | | | | | | | | | | commit c1118b3602c2329671ad5ec8bdf8e374323d6343 upstream. On x86_64, kernel text mappings are mapped read-only with CONFIG_DEBUG_RODATA. In that case, KVM will fail to patch VMCALL instructions to VMMCALL as required on AMD processors. The failure mode is currently a divide-by-zero exception, which obviously is a KVM bug that has to be fixed. However, picking the right instruction between VMCALL and VMMCALL will be faster and will help if you cannot upgrade the hypervisor. Reported-by: Chris Webb <chris@arachsys.com> Tested-by: Chris Webb <chris@arachsys.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
* crypto: ghash-clmulni-intel - use C implementation for setkey()Ard Biesheuvel2015-01-012-31/+11
| | | | | | | | | | | | | | | | | | | commit 8ceee72808d1ae3fb191284afc2257a2be964725 upstream. The GHASH setkey() function uses SSE registers but fails to call kernel_fpu_begin()/kernel_fpu_end(). Instead of adding these calls, and then having to deal with the restriction that they cannot be called from interrupt context, move the setkey() implementation to the C domain. Note that setkey() does not use any particular SSE features and is not expected to become a performance bottleneck. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Fixes: 0e1227d356e9b (crypto: ghash - Add PCLMULQDQ accelerated implementation) Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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