- 17 Jan, 2018 18 commits
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Steve Wise authored
commit bc52e9ca upstream. __flush_qp() has a race condition where during the flush operation, the qp lock is released allowing another thread to possibly post a WR, which corrupts the queue state, possibly causing crashes. The lock was released to preserve the cq/qp locking hierarchy of cq first, then qp. However releasing the qp lock is not necessary; both RQ and SQ CQ locks can be acquired first, followed by the qp lock, and then the RQ and SQ flushing can be done w/o unlocking. Signed-off-by:
Steve Wise <swise@opengridcomputing.com> Signed-off-by:
Doug Ledford <dledford@redhat.com> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Steve Wise authored
commit cbb40fad upstream. The ULPs completion handler should only be called if the CQ is armed for notification. Signed-off-by:
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Rafael J. Wysocki authored
commit 98b8e4e5 upstream. Calling acpi_wmi_init() at the subsys_initcall() level causes ordering issues to appear on some systems and they are difficult to reproduce, because there is no guaranteed ordering between subsys_initcall() calls, so they may occur in different orders on different systems. In particular, commit 86d9f485 (mm/slab: fix kmemcg cache creation delayed issue) exposed one of these issues where genl_init() and acpi_wmi_init() are both called at the same initcall level, but the former must run before the latter so as to avoid a NULL pointer dereference. For this reason, move the acpi_wmi_init() invocation to the initcall_sync level which should still be early enough for things to work correctly in the WMI land. Link: https://marc.info/?t=151274596700002&r=1&w=2Reported-by:
Jonathan McDowell <noodles@earth.li> Reported-by:
Joonsoo Kim <iamjoonsoo.kim@lge.com> Tested-by:
Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by:
Darren Hart (VMware) <dvhart@infradead.org> Signed-off-by:
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Jim Mattson authored
commit 0cb5b306 upstream. Guest GPR values are live in the hardware GPRs at VM-exit. Do not leave any guest values in hardware GPRs after the guest GPR values are saved to the vcpu_vmx structure. This is a partial mitigation for CVE 2017-5715 and CVE 2017-5753. Specifically, it defeats the Project Zero PoC for CVE 2017-5715. Suggested-by:
Eric Northup <digitaleric@google.com> Signed-off-by:
Jim Mattson <jmattson@google.com> Reviewed-by:
Benjamin Serebrin <serebrin@google.com> Reviewed-by:
Andrew Honig <ahonig@google.com> [Paolo: Add AMD bits, Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>] Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com> Signed-off-by:
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Tejun Heo authored
commit 74d0833c upstream. While teaching css_task_iter to handle skipping over tasks which aren't group leaders, bc2fb7ed ("cgroup: add @flags to css_task_iter_start() and implement CSS_TASK_ITER_PROCS") introduced a silly bug. CSS_TASK_ITER_PROCS is implemented by repeating css_task_iter_advance() while the advanced cursor is pointing to a non-leader thread. However, the cursor variable, @l, wasn't updated when the iteration has to advance to the next css_set and the following repetition would operate on the terminal @l from the previous iteration which isn't pointing to a valid task leading to oopses like the following or infinite looping. BUG: unable to handle kernel NULL pointer dereference at 0000000000000254 IP: __task_pid_nr_ns+0xc7/0xf0 PGD 0 P4D 0 Oops: 0000 [#1] SMP ... CPU: 2 PID: 1 Comm: systemd Not tainted 4.14.4-200.fc26.x86_64 #1 Hardware name: System manufacturer System Product Name/PRIME B350M-A, BIOS 3203 11/09/2017 task: ffff88c4baee8000 task.stack: ffff96d5c3158000 RIP: 0010:__task_pid_nr_ns+0xc7/0xf0 RSP: 0018:ffff96d5c315bd50 EFLAGS: 00010206 RAX: 0000000000000000 RBX: ffff88c4b68c6000 RCX: 0000000000000250 RDX: ffffffffa5e47960 RSI: 0000000000000000 RDI: ffff88c490f6ab00 RBP: ffff96d5c315bd50 R08: 0000000000001000 R09: 0000000000000005 R10: ffff88c4be006b80 R11: ffff88c42f1b8004 R12: ffff96d5c315bf18 R13: ffff88c42d7dd200 R14: ffff88c490f6a510 R15: ffff88c4b68c6000 FS: 00007f9446f8ea00(0000) GS:ffff88c4be680000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000254 CR3: 00000007f956f000 CR4: 00000000003406e0 Call Trace: cgroup_procs_show+0x19/0x30 cgroup_seqfile_show+0x4c/0xb0 kernfs_seq_show+0x21/0x30 seq_read+0x2ec/0x3f0 kernfs_fop_read+0x134/0x180 __vfs_read+0x37/0x160 ? security_file_permission+0x9b/0xc0 vfs_read+0x8e/0x130 SyS_read+0x55/0xc0 entry_SYSCALL_64_fastpath+0x1a/0xa5 RIP: 0033:0x7f94455f942d RSP: 002b:00007ffe81ba2d00 EFLAGS: 00000293 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00005574e2233f00 RCX: 00007f94455f942d RDX: 0000000000001000 RSI: 00005574e2321a90 RDI: 000000000000002b RBP: 0000000000000000 R08: 00005574e2321a90 R09: 00005574e231de60 R10: 00007f94458c8b38 R11: 0000000000000293 R12: 00007f94458c8ae0 R13: 00007ffe81ba3800 R14: 0000000000000000 R15: 00005574e2116560 Code: 04 74 0e 89 f6 48 8d 04 76 48 8d 04 c5 f0 05 00 00 48 8b bf b8 05 00 00 48 01 c7 31 c0 48 8b 0f 48 85 c9 74 18 8b b2 30 08 00 00 <3b> 71 04 77 0d 48 c1 e6 05 48 01 f1 48 3b 51 38 74 09 5d c3 8b RIP: __task_pid_nr_ns+0xc7/0xf0 RSP: ffff96d5c315bd50 Fix it by moving the initialization of the cursor below the repeat label. While at it, rename it to @next for readability. Signed-off-by:
Tejun Heo <tj@kernel.org> Fixes: bc2fb7ed ("cgroup: add @flags to css_task_iter_start() and implement CSS_TASK_ITER_PROCS") Reported-by:
Laura Abbott <labbott@redhat.com> Reported-by:
Bronek Kozicki <brok@incorrekt.com> Reported-by:
George Amanakis <gamanakis@gmail.com> Signed-off-by:
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Maciej W. Rozycki authored
commit c8c5a3a2 upstream. Complement commit c23b3d1a ("MIPS: ptrace: Change GP regset to use correct core dump register layout") and also reject outsized PTRACE_SETREGSET requests to the NT_PRFPREG regset, like with the NT_PRSTATUS regset. Signed-off-by:
Maciej W. Rozycki <macro@mips.com> Fixes: c23b3d1a ("MIPS: ptrace: Change GP regset to use correct core dump register layout") Cc: James Hogan <james.hogan@mips.com> Cc: Paul Burton <Paul.Burton@mips.com> Cc: Alex Smith <alex@alex-smith.me.uk> Cc: Dave Martin <Dave.Martin@arm.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17930/Signed-off-by:
Ralf Baechle <ralf@linux-mips.org> Signed-off-by:
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Maciej W. Rozycki authored
commit 006501e0 upstream. Complement commit d614fd58 ("mips/ptrace: Preserve previous registers for short regset write") and like with the PTRACE_GETREGSET ptrace(2) request also apply a BUILD_BUG_ON check for the size of the `elf_fpreg_t' type in the PTRACE_SETREGSET request handler. Signed-off-by:
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Maciej W. Rozycki authored
commit be07a6a1 upstream. Fix a commit 72b22bba ("MIPS: Don't assume 64-bit FP registers for FP regset") public API regression, then activated by commit 1db1af84 ("MIPS: Basic MSA context switching support"), that caused the FCSR register not to be read or written for CONFIG_CPU_HAS_MSA kernel configurations (regardless of actual presence or absence of the MSA feature in a given processor) with ptrace(2) PTRACE_GETREGSET and PTRACE_SETREGSET requests nor recorded in core dumps. This is because with !CONFIG_CPU_HAS_MSA configurations the whole of `elf_fpregset_t' array is bulk-copied as it is, which includes the FCSR in one half of the last, 33rd slot, whereas with CONFIG_CPU_HAS_MSA configurations array elements are copied individually, and then only the leading 32 FGR slots while the remaining slot is ignored. Correct the code then such that only FGR slots are copied in the respective !MSA and MSA helpers an then the FCSR slot is handled separately in common code. Use `ptrace_setfcr31' to update the FCSR too, so that the read-only mask is respected. Retrieving a correct value of FCSR is important in debugging not only for the human to be able to get the right interpretation of the situation, but for correct operation of GDB as well. This is because the condition code bits in FSCR are used by GDB to determine the location to place a breakpoint at when single-stepping through an FPU branch instruction. If such a breakpoint is placed incorrectly (i.e. with the condition reversed), then it will be missed, likely causing the debuggee to run away from the control of GDB and consequently breaking the process of investigation. Fortunately GDB continues using the older PTRACE_GETFPREGS ptrace(2) request which is unaffected, so the regression only really hits with post-mortem debug sessions using a core dump file, in which case execution, and consequently single-stepping through branches is not possible. Of course core files created by buggy kernels out there will have the value of FCSR recorded clobbered, but such core files cannot be corrected and the person using them simply will have to be aware that the value of FCSR retrieved is not reliable. Which also means we can likely get away without defining a replacement API which would ensure a correct value of FSCR to be retrieved, or none at all. This is based on previous work by Alex Smith, extensively rewritten. Signed-off-by:
Alex Smith <alex@alex-smith.me.uk> Signed-off-by:
James Hogan <james.hogan@mips.com> Signed-off-by:
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Maciej W. Rozycki authored
commit 80b3ffce upstream. Update commit d614fd58 ("mips/ptrace: Preserve previous registers for short regset write") bug and consistently consume all data supplied to `fpr_set_msa' with the ptrace(2) PTRACE_SETREGSET request, such that a zero data buffer counter is returned where insufficient data has been given to fill a whole number of FP general registers. In reality this is not going to happen, as the caller is supposed to only supply data covering a whole number of registers and it is verified in `ptrace_regset' and again asserted in `fpr_set', however structuring code such that the presence of trailing partial FP general register data causes `fpr_set_msa' to return with a non-zero data buffer counter makes it appear that this trailing data will be used if there are subsequent writes made to FP registers, which is going to be the case with the FCSR once the missing write to that register has been fixed. Fixes: d614fd58 ("mips/ptrace: Preserve previous registers for short regset write") Signed-off-by:
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Maciej W. Rozycki authored
commit dc24d0ed upstream. Complement commit d614fd58 ("mips/ptrace: Preserve previous registers for short regset write") and ensure that no partial register write attempt is made with PTRACE_SETREGSET, as we do not preinitialize any temporaries used to hold incoming register data and consequently random data could be written. It is the responsibility of the caller, such as `ptrace_regset', to arrange for writes to span whole registers only, so here we only assert that it has indeed happened. Signed-off-by:
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Maciej W. Rozycki authored
commit a03fe725 upstream. In preparation to fix a commit 72b22bba ("MIPS: Don't assume 64-bit FP registers for FP regset") FCSR access regression factor out NT_PRFPREG regset access helpers for the non-MSA and the MSA variants respectively, to avoid having to deal with excessive indentation in the actual fix. No functional change, however use `target->thread.fpu.fpr[0]' rather than `target->thread.fpu.fpr[i]' for FGR holding type size determination as there's no `i' variable to refer to anymore, and for the factored out `i' variable declaration use `unsigned int' rather than `unsigned' as its type, following the common style. Signed-off-by:
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Maciej W. Rozycki authored
commit b67336ee upstream. Fix an API loophole introduced with commit 9791554b ("MIPS,prctl: add PR_[GS]ET_FP_MODE prctl options for MIPS"), where the caller of prctl(2) is incorrectly allowed to make a change to CP0.Status.FR or CP0.Config5.FRE register bits even if CONFIG_MIPS_O32_FP64_SUPPORT has not been enabled, despite that an executable requesting the mode requested via ELF file annotation would not be allowed to run in the first place, or for n64 and n64 ABI tasks which do not have non-default modes defined at all. Add suitable checks to `mips_set_process_fp_mode' and bail out if an invalid mode change has been requested for the ABI in effect, even if the FPU hardware or emulation would otherwise allow it. Always succeed however without taking any further action if the mode requested is the same as one already in effect, regardless of whether any mode change, should it be requested, would actually be allowed for the task concerned. Signed-off-by:
Paul Burton <paul.burton@mips.com> Cc: James Hogan <james.hogan@mips.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/17800/Signed-off-by:
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Bart Van Assche authored
commit a1ffa467 upstream. Make sure that the initiator port GUID is stored in ch->ini_guid. Note: when initiating a connection sgid and dgid members in struct sa_path_rec represent the source and destination GIDs. When accepting a connection however sgid represents the destination GID and dgid the source GID. Fixes: commit 2bce1a6d ("IB/srpt: Accept GUIDs as port names") Signed-off-by:
Bart Van Assche <bart.vanassche@wdc.com> Signed-off-by:
Jason Gunthorpe <jgg@mellanox.com> Signed-off-by:
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Bart Van Assche authored
commit bec40c26 upstream. With the SRP protocol all RDMA operations are initiated by the target. Since no RDMA operations are initiated by the initiator, do not grant the initiator permission to submit RDMA reads or writes to the target. Signed-off-by:
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Wolfgang Grandegger authored
commit d5b42e66 upstream. The "set_bittiming" callback treats a positive return value as error! For that reason "can_changelink()" will quit silently after setting the bittiming values without processing ctrlmode, restart-ms, etc. Signed-off-by:
Wolfgang Grandegger <wg@grandegger.com> Signed-off-by:
Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by:
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Oliver Hartkopp authored
commit b4c2951a upstream. Picking up the patch from Serhey Popovych (commit 191cdb38, "veth: Be more robust on network device creation when no attributes"). When the peer name attribute is not provided the former implementation tries to register the given device name twice ... which leads to -EEXIST. If only one device name is given apply an automatic generated and valid name for the peer. Cc: Serhey Popovych <serhe.popovych@gmail.com> Signed-off-by:
Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by:
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Wanpeng Li authored
commit e39d200f upstream. Reported by syzkaller: BUG: KASAN: stack-out-of-bounds in write_mmio+0x11e/0x270 [kvm] Read of size 8 at addr ffff8803259df7f8 by task syz-executor/32298 CPU: 6 PID: 32298 Comm: syz-executor Tainted: G OE 4.15.0-rc2+ #18 Hardware name: LENOVO ThinkCentre M8500t-N000/SHARKBAY, BIOS FBKTC1AUS 02/16/2016 Call Trace: dump_stack+0xab/0xe1 print_address_description+0x6b/0x290 kasan_report+0x28a/0x370 write_mmio+0x11e/0x270 [kvm] emulator_read_write_onepage+0x311/0x600 [kvm] emulator_read_write+0xef/0x240 [kvm] emulator_fix_hypercall+0x105/0x150 [kvm] em_hypercall+0x2b/0x80 [kvm] x86_emulate_insn+0x2b1/0x1640 [kvm] x86_emulate_instruction+0x39a/0xb90 [kvm] handle_exception+0x1b4/0x4d0 [kvm_intel] vcpu_enter_guest+0x15a0/0x2640 [kvm] kvm_arch_vcpu_ioctl_run+0x549/0x7d0 [kvm] kvm_vcpu_ioctl+0x479/0x880 [kvm] do_vfs_ioctl+0x142/0x9a0 SyS_ioctl+0x74/0x80 entry_SYSCALL_64_fastpath+0x23/0x9a The path of patched vmmcall will patch 3 bytes opcode 0F 01 C1(vmcall) to the guest memory, however, write_mmio tracepoint always prints 8 bytes through *(u64 *)val since kvm splits the mmio access into 8 bytes. This leaks 5 bytes from the kernel stack (CVE-2017-17741). This patch fixes it by just accessing the bytes which we operate on. Before patch: syz-executor-5567 [007] .... 51370.561696: kvm_mmio: mmio write len 3 gpa 0x10 val 0x1ffff10077c1010f After patch: syz-executor-13416 [002] .... 51302.299573: kvm_mmio: mmio write len 3 gpa 0x10 val 0xc1010f Reported-by:
Dmitry Vyukov <dvyukov@google.com> Reviewed-by:
Darren Kenny <darren.kenny@oracle.com> Reviewed-by:
Marc Zyngier <marc.zyngier@arm.com> Tested-by:
Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by:
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Suren Baghdasaryan authored
commit fbc7c07e upstream. When system is under memory pressure it is observed that dm bufio shrinker often reclaims only one buffer per scan. This change fixes the following two issues in dm bufio shrinker that cause this behavior: 1. ((nr_to_scan - freed) <= retain_target) condition is used to terminate slab scan process. This assumes that nr_to_scan is equal to the LRU size, which might not be correct because do_shrink_slab() in vmscan.c calculates nr_to_scan using multiple inputs. As a result when nr_to_scan is less than retain_target (64) the scan will terminate after the first iteration, effectively reclaiming one buffer per scan and making scans very inefficient. This hurts vmscan performance especially because mutex is acquired/released every time dm_bufio_shrink_scan() is called. New implementation uses ((LRU size - freed) <= retain_target) condition for scan termination. LRU size can be safely determined inside __scan() because this function is called after dm_bufio_lock(). 2. do_shrink_slab() uses value returned by dm_bufio_shrink_count() to determine number of freeable objects in the slab. However dm_bufio always retains retain_target buffers in its LRU and will terminate a scan when this mark is reached. Therefore returning the entire LRU size from dm_bufio_shrink_count() is misleading because that does not represent the number of freeable objects that slab will reclaim during a scan. Returning (LRU size - retain_target) better represents the number of freeable objects in the slab. This way do_shrink_slab() returns 0 when (LRU size < retain_target) and vmscan will not try to scan this shrinker avoiding scans that will not reclaim any memory. Test: tested using Android device running <AOSP>/system/extras/alloc-stress that generates memory pressure and causes intensive shrinker scans Signed-off-by:
Suren Baghdasaryan <surenb@google.com> Signed-off-by:
Mike Snitzer <snitzer@redhat.com> Signed-off-by:
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- 10 Jan, 2018 22 commits
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Greg Kroah-Hartman authored
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Christian Borntraeger authored
commit c2cf265d upstream. We must not go beyond the pre-allocated buffer. This can happen when a new memory slot is added during migration. Reported-by:
David Hildenbrand <david@redhat.com> Signed-off-by:
Christian Borntraeger <borntraeger@de.ibm.com> Fixes: 190df4a2 (KVM: s390: CMMA tracking, ESSA emulation, migration mode) Reviewed-by:
Cornelia Huck <cohuck@redhat.com> Reviewed-by:
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Christian Borntraeger authored
commit 32aa144f upstream. When multiple memory slots are present the cmma migration code does not allocate enough memory for the bitmap. The memory slots are sorted in reverse order, so we must use gfn and size of slot[0] instead of the last one. Signed-off-by:
Claudio Imbrenda <imbrenda@linux.vnet.ibm.com> Fixes: 190df4a2 (KVM: s390: CMMA tracking, ESSA emulation, migration mode) Reviewed-by:
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Boris Brezillon authored
commit fee4380f upstream. In the current driver, OOB bytes are accessed in raw mode, and when a page access is done with NDCR_SPARE_EN set and NDCR_ECC_EN cleared, the driver must read the whole spare area (64 bytes in case of a 2k page, 16 bytes for a 512 page). The driver was only reading the free OOB bytes, which was leaving some unread data in the FIFO and was somehow leading to a timeout. We could patch the driver to read ->spare_size + ->ecc_size instead of just ->spare_size when READOOB is requested, but we'd better make in-band and OOB accesses consistent. Since the driver is always accessing in-band data in non-raw mode (with the ECC engine enabled), we should also access OOB data in this mode. That's particularly useful when using the BCH engine because in this mode the free OOB bytes are also ECC protected. Fixes: 43bcfd2b ("mtd: nand: pxa3xx: Add driver-specific ECC BCH support") Reported-by:
Sean Nyekjær <sean.nyekjaer@prevas.dk> Tested-by:
Willy Tarreau <w@1wt.eu> Signed-off-by:
Boris Brezillon <boris.brezillon@free-electrons.com> Acked-by:
Ezequiel Garcia <ezequiel@vanguardiasur.com.ar> Tested-by:
Robert Jarzmik <robert.jarzmik@free.fr> Signed-off-by:
Richard Weinberger <richard@nod.at> Signed-off-by:
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Helge Deller authored
commit 310d8278 upstream. Add qemu idle sleep support when running under qemu with SeaBIOS PDC firmware. Like the power architecture we use the "or" assembler instructions, which translate to nops on real hardware, to indicate that qemu shall idle sleep. Signed-off-by:
Helge Deller <deller@gmx.de> Cc: Richard Henderson <rth@twiddle.net> Signed-off-by:
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Helge Deller authored
commit 88776c0e upstream. Qemu for PARISC reported on a 32bit SMP parisc kernel strange failures about "Not-handled unaligned insn 0x0e8011d6 and 0x0c2011c9." Those opcodes evaluate to the ldcw() assembly instruction which requires (on 32bit) an alignment of 16 bytes to ensure atomicity. As it turns out, qemu is correct and in our assembly code in entry.S and pacache.S we don't pay attention to the required alignment. This patch fixes the problem by aligning the lock offset in assembly code in the same manner as we do in our C-code. Signed-off-by:
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John Johansen authored
commit 5b9f57cf upstream. When the mount code was refactored for Labels it was not correctly updated to check whether policy supported mediation of the mount class. This causes a regression when the kernel feature set is reported as supporting mount and policy is pinned to a feature set that does not support mount mediation. BugLink: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=882697#41 Fixes: 2ea3ffb7 ("apparmor: add mount mediation") Reported-by:
Fabian Grünbichler <f.gruenbichler@proxmox.com> Signed-off-by:
John Johansen <john.johansen@canonical.com> Signed-off-by:
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Tom Lendacky authored
commit f4e9b7af upstream. The size for the Microcode Patch Block (MPB) for an AMD family 17h processor is 3200 bytes. Add a #define for fam17h so that it does not default to 2048 bytes and fail a microcode load/update. Signed-off-by:
Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by:
Thomas Gleixner <tglx@linutronix.de> Reviewed-by:
Borislav Petkov <bp@alien8.de> Link: https://lkml.kernel.org/r/20171130224640.15391.40247.stgit@tlendack-t1.amdoffice.netSigned-off-by:
Ingo Molnar <mingo@kernel.org> Cc: Alice Ferrazzi <alicef@gentoo.org> Signed-off-by:
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Aaron Ma authored
commit 10d90030 upstream. The touchpad of Lenovo Thinkpad L480 reports it's version as 15. Signed-off-by:
Aaron Ma <aaron.ma@canonical.com> Signed-off-by:
Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by:
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John Sperbeck authored
commit ecb101ae upstream. The recent refactoring of the powerpc page fault handler in commit c3350602 ("powerpc/mm: Make bad_area* helper functions") caused access to protected memory regions to indicate SEGV_MAPERR instead of the traditional SEGV_ACCERR in the si_code field of a user-space signal handler. This can confuse debug libraries that temporarily change the protection of memory regions, and expect to use SEGV_ACCERR as an indication to restore access to a region. This commit restores the previous behavior. The following program exhibits the issue: $ ./repro read || echo "FAILED" $ ./repro write || echo "FAILED" $ ./repro exec || echo "FAILED" #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include <signal.h> #include <sys/mman.h> #include <assert.h> static void segv_handler(int n, siginfo_t *info, void *arg) { _exit(info->si_code == SEGV_ACCERR ? 0 : 1); } int main(int argc, char **argv) { void *p = NULL; struct sigaction act = { .sa_sigaction = segv_handler, .sa_flags = SA_SIGINFO, }; assert(argc == 2); p = mmap(NULL, getpagesize(), (strcmp(argv[1], "write") == 0) ? PROT_READ : 0, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0); assert(p != MAP_FAILED); assert(sigaction(SIGSEGV, &act, NULL) == 0); if (strcmp(argv[1], "read") == 0) printf("%c", *(unsigned char *)p); else if (strcmp(argv[1], "write") == 0) *(unsigned char *)p = 0; else if (strcmp(argv[1], "exec") == 0) ((void (*)(void))p)(); return 1; /* failed to generate SEGV */ } Fixes: c3350602 ("powerpc/mm: Make bad_area* helper functions") Signed-off-by:
John Sperbeck <jsperbeck@google.com> Acked-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org> [mpe: Add commit references in change log] Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Signed-off-by:
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Vineet Gupta authored
commit 79435ac7 upstream. This used to setup the LP_COUNT register automatically, but now has been removed. There was an earlier fix 3c7c7a2f which fixed instance in delay.h but somehow missed this one as gcc change had not made its way into production toolchains and was not pedantic as it is now ! Signed-off-by:
Vineet Gupta <vgupta@synopsys.com> Signed-off-by:
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Robin Murphy authored
commit 563b5cbe upstream. For PCI devices behind an aliasing PCIe-to-PCI/X bridge, the bridge alias to DevFn 0.0 on the subordinate bus may match the original RID of the device, resulting in the same SID being present in the device's fwspec twice. This causes trouble later in arm_smmu_write_strtab_ent() when we wind up visiting the STE a second time and find it already live. Avoid the issue by giving arm_smmu_install_ste_for_dev() the cleverness to skip over duplicates. It seems mildly counterintuitive compared to preventing the duplicates from existing in the first place, but since the DT and ACPI probe paths build their fwspecs differently, this is actually the cleanest and most self-contained way to deal with it. Fixes: 8f785154 ("iommu/arm-smmu: Implement of_xlate() for SMMUv3") Reported-by:
Tomasz Nowicki <tomasz.nowicki@caviumnetworks.com> Tested-by:
Tomasz Nowicki <Tomasz.Nowicki@cavium.com> Tested-by:
Jayachandran C. <jnair@caviumnetworks.com> Signed-off-by:
Robin Murphy <robin.murphy@arm.com> Signed-off-by:
Will Deacon <will.deacon@arm.com> Signed-off-by:
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Jean-Philippe Brucker authored
commit 57d72e15 upstream. Kasan reports a double free when finalise_stage_fn fails: the io_pgtable ops are freed by arm_smmu_domain_finalise and then again by arm_smmu_domain_free. Prevent this by leaving pgtbl_ops empty on failure. Fixes: 48ec83bc ("iommu/arm-smmu: Add initial driver support for ARM SMMUv3 devices") Reviewed-by:
Jean-Philippe Brucker <jean-philippe.brucker@arm.com> Signed-off-by:
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Oleg Nesterov authored
commit 42691579 upstream. complete_signal() checks SIGNAL_UNKILLABLE before it starts to destroy the thread group, today this is wrong in many ways. If nothing else, fatal_signal_pending() should always imply that the whole thread group (except ->group_exit_task if it is not NULL) is killed, this check breaks the rule. After the previous changes we can rely on sig_task_ignored(); sig_fatal(sig) && SIGNAL_UNKILLABLE can only be true if we actually want to kill this task and sig == SIGKILL OR it is traced and debugger can intercept the signal. This should hopefully fix the problem reported by Dmitry. This test-case static int init(void *arg) { for (;;) pause(); } int main(void) { char stack[16 * 1024]; for (;;) { int pid = clone(init, stack + sizeof(stack)/2, CLONE_NEWPID | SIGCHLD, NULL); assert(pid > 0); assert(ptrace(PTRACE_ATTACH, pid, 0, 0) == 0); assert(waitpid(-1, NULL, WSTOPPED) == pid); assert(ptrace(PTRACE_DETACH, pid, 0, SIGSTOP) == 0); assert(syscall(__NR_tkill, pid, SIGKILL) == 0); assert(pid == wait(NULL)); } } triggers the WARN_ON_ONCE(!(task->jobctl & JOBCTL_STOP_PENDING)) in task_participate_group_stop(). do_signal_stop()->signal_group_exit() checks SIGNAL_GROUP_EXIT and return false, but task_set_jobctl_pending() checks fatal_signal_pending() and does not set JOBCTL_STOP_PENDING. And his should fix the minor security problem reported by Kyle, SECCOMP_RET_TRACE can miss fatal_signal_pending() the same way if the task is the root of a pid namespace. Link: http://lkml.kernel.org/r/20171103184246.GD21036@redhat.comSigned-off-by:
Oleg Nesterov <oleg@redhat.com> Reported-by:
Kyle Huey <me@kylehuey.com> Reviewed-by:
Kees Cook <keescook@chromium.org> Tested-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
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Oleg Nesterov authored
commit ac253850 upstream. Change sig_task_ignored() to drop the SIG_DFL && !sig_kernel_only() signals even if force == T. This simplifies the next change and this matches the same check in get_signal() which will drop these signals anyway. Link: http://lkml.kernel.org/r/20171103184227.GC21036@redhat.comSigned-off-by:
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Oleg Nesterov authored
commit 628c1bcb upstream. The comment in sig_ignored() says "Tracers may want to know about even ignored signals" but SIGKILL can not be reported to debugger and it is just wrong to return 0 in this case: SIGKILL should only kill the SIGNAL_UNKILLABLE task if it comes from the parent ns. Change sig_ignored() to ignore ->ptrace if sig == SIGKILL and rely on sig_task_ignored(). SISGTOP coming from within the namespace is not really right too but at least debugger can intercept it, and we can't drop it here because this will break "gdb -p 1": ptrace_attach() won't work. Perhaps we will add another ->ptrace check later, we will see. Link: http://lkml.kernel.org/r/20171103184206.GB21036@redhat.comSigned-off-by:
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Rafael J. Wysocki authored
commit 7d5905dc upstream. After commit 890da9cf (Revert "x86: do not use cpufreq_quick_get() for /proc/cpuinfo "cpu MHz"") the "cpu MHz" number in /proc/cpuinfo on x86 can be either the nominal CPU frequency (which is constant) or the frequency most recently requested by a scaling governor in cpufreq, depending on the cpufreq configuration. That is somewhat inconsistent and is different from what it was before 4.13, so in order to restore the previous behavior, make it report the current CPU frequency like the scaling_cur_freq sysfs file in cpufreq. To that end, modify the /proc/cpuinfo implementation on x86 to use aperfmperf_snapshot_khz() to snapshot the APERF and MPERF feedback registers, if available, and use their values to compute the CPU frequency to be reported as "cpu MHz". However, do that carefully enough to avoid accumulating delays that lead to unacceptable access times for /proc/cpuinfo on systems with many CPUs. Run aperfmperf_snapshot_khz() once on all CPUs asynchronously at the /proc/cpuinfo open time, add a single delay upfront (if necessary) at that point and simply compute the current frequency while running show_cpuinfo() for each individual CPU. Also, to avoid slowing down /proc/cpuinfo accesses too much, reduce the default delay between consecutive APERF and MPERF reads to 10 ms, which should be sufficient to get large enough numbers for the frequency computation in all cases. Fixes: 890da9cf (Revert "x86: do not use cpufreq_quick_get() for /proc/cpuinfo "cpu MHz"") Signed-off-by:
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Rafael J. Wysocki authored
commit b29c6ef7 upstream. Even though aperfmperf_snapshot_khz() caches the samples.khz value to return if called again in a sufficiently short time, its caller, arch_freq_get_on_cpu(), still uses smp_call_function_single() to run it which may allow user space to trigger an IPI storm by reading from the scaling_cur_freq cpufreq sysfs file in a tight loop. To avoid that, move the decision on whether or not to return the cached samples.khz value to arch_freq_get_on_cpu(). This change was part of commit 941f5f0f ("x86: CPU: Fix up "cpu MHz" in /proc/cpuinfo"), but it was not the reason for the revert and it remains applicable. Fixes: 4815d3c5 (cpufreq: x86: Make scaling_cur_freq behave more as expected) Signed-off-by:
WANG Chao <chao.wang@ucloud.cn> Signed-off-by:
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David Howells authored
commit 98801506 upstream. Fix the default for fscache_maybe_release_page() for when the cookie isn't valid or the page isn't cached. It mustn't return false as that indicates the page cannot yet be freed. The problem with the default is that if, say, there's no cache, but a network filesystem's pages are using up almost all the available memory, a system can OOM because the filesystem ->releasepage() op will not allow them to be released as fscache_maybe_release_page() incorrectly prevents it. This can be tested by writing a sequence of 512MiB files to an AFS mount. It does not affect NFS or CIFS because both of those wrap the call in a check of PG_fscache and it shouldn't bother Ceph as that only has PG_private set whilst writeback is in progress. This might be an issue for 9P, however. Note that the pages aren't entirely stuck. Removing a file or unmounting will clear things because that uses ->invalidatepage() instead. Fixes: 201a1542 ("FS-Cache: Handle pages pending storage that get evicted under OOM conditions") Reported-by:
Marc Dionne <marc.dionne@auristor.com> Signed-off-by:
David Howells <dhowells@redhat.com> Reviewed-by:
Jeff Layton <jlayton@redhat.com> Acked-by:
Al Viro <viro@zeniv.linux.org.uk> Tested-by:
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Stefan Brüns authored
commit e2bf801e upstream. Include the OF-based modalias in the uevent sent when registering devices on the sunxi RSB bus, so that user space has a chance to autoload the kernel module for the device. Fixes a regression caused by commit 3f241bfa ("arm64: allwinner: a64: pine64: Use dcdc1 regulator for mmc0"). When the axp20x-rsb module for the AXP803 PMIC is built as a module, it is not loaded and the system ends up with an disfunctional MMC controller. Fixes: d787dcdb ("bus: sunxi-rsb: Add driver for Allwinner Reduced Serial Bus") Acked-by:
Chen-Yu Tsai <wens@csie.org> Signed-off-by:
Stefan Brüns <stefan.bruens@rwth-aachen.de> Signed-off-by:
Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by:
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Lucas De Marchi authored
commit 30414f30 upstream. Display WA #1183 was recently added to workaround "Failures when enabling DPLL0 with eDP link rate 2.16 or 4.32 GHz and CD clock frequency 308.57 or 617.14 MHz (CDCLK_CTL CD Frequency Select 10b or 11b) used in this enabling or in previous enabling." This workaround was designed to minimize the impact only to save the bad case with that link rates. But HW engineers indicated that it should be safe to apply broadly, although they were expecting the DPLL0 link rate to be unchanged on runtime. We need to cover 2 cases: when we are in fact enabling DPLL0 and when we are just changing the frequency with small differences. This is based on previous patch by Rodrigo Vivi with suggestions from Ville Syrjälä. Cc: Arthur J Runyan <arthur.j.runyan@intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> Signed-off-by:
Lucas De Marchi <lucas.demarchi@intel.com> Reviewed-by:
Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by:
Rodrigo Vivi <rodrigo.vivi@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20171204232210.4958-1-lucas.demarchi@intel.com (cherry picked from commit 53421c2f) [ Lucas: Backport to 4.15 adding back variable that has been removed on commits not meant to be backported ] Signed-off-by:
Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20180102201837.6812-1-lucas.demarchi@intel.comSigned-off-by:
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Ville Syrjälä authored
commit 3488d023 upstream. Prevent the DMC from destroying GMBUS transfers on GLK. GMBUS lives in PG1 so DC off is all we need. Signed-off-by:
Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com> (cherry picked from commit 156961ae) Signed-off-by:
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