- 22 Oct, 2015 19 commits
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Matt Fleming authored
commit a5caa209 upstream. Beginning with UEFI v2.5 EFI_PROPERTIES_TABLE was introduced that signals that the firmware PE/COFF loader supports splitting code and data sections of PE/COFF images into separate EFI memory map entries. This allows the kernel to map those regions with strict memory protections, e.g. EFI_MEMORY_RO for code, EFI_MEMORY_XP for data, etc. Unfortunately, an unwritten requirement of this new feature is that the regions need to be mapped with the same offsets relative to each other as observed in the EFI memory map. If this is not done crashes like this may occur, BUG: unable to handle kernel paging request at fffffffefe6086dd IP: [<fffffffefe6086dd>] 0xfffffffefe6086dd Call Trace: [<ffffffff8104c90e>] efi_call+0x7e/0x100 [<ffffffff81602091>] ? virt_efi_set_variable+0x61/0x90 [<ffffffff8104c583>] efi_delete_dummy_variable+0x63/0x70 [<ffffffff81f4e4aa>] efi_enter_virtual_mode+0x383/0x392 [<ffffffff81f37e1b>] start_kernel+0x38a/0x417 [<ffffffff81f37495>] x86_64_start_reservations+0x2a/0x2c [<ffffffff81f37582>] x86_64_start_kernel+0xeb/0xef Here 0xfffffffefe6086dd refers to an address the firmware expects to be mapped but which the OS never claimed was mapped. The issue is that included in these regions are relative addresses to other regions which were emitted by the firmware toolchain before the "splitting" of sections occurred at runtime. Needless to say, we don't satisfy this unwritten requirement on x86_64 and instead map the EFI memory map entries in reverse order. The above crash is almost certainly triggerable with any kernel newer than v3.13 because that's when we rewrote the EFI runtime region mapping code, in commit d2f7cbe7 ("x86/efi: Runtime services virtual mapping"). For kernel versions before v3.13 things may work by pure luck depending on the fragmentation of the kernel virtual address space at the time we map the EFI regions. Instead of mapping the EFI memory map entries in reverse order, where entry N has a higher virtual address than entry N+1, map them in the same order as they appear in the EFI memory map to preserve this relative offset between regions. This patch has been kept as small as possible with the intention that it should be applied aggressively to stable and distribution kernels. It is very much a bugfix rather than support for a new feature, since when EFI_PROPERTIES_TABLE is enabled we must map things as outlined above to even boot - we have no way of asking the firmware not to split the code/data regions. In fact, this patch doesn't even make use of the more strict memory protections available in UEFI v2.5. That will come later. Suggested-by:
Ard Biesheuvel <ard.biesheuvel@linaro.org> Reported-by:
Matt Fleming <matt.fleming@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Chun-Yi <jlee@suse.com> Cc: Dave Young <dyoung@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: James Bottomley <JBottomley@Odin.com> Cc: Lee, Chun-Yi <jlee@suse.com> Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Jones <pjones@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1443218539-7610-2-git-send-email-matt@codeblueprint.co.ukSigned-off-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Dirk Müller authored
commit d2922422 upstream. The cpu feature flags are not ever going to change, so warning everytime can cause a lot of kernel log spam (in our case more than 10GB/hour). The warning seems to only occur when nested virtualization is enabled, so it's probably triggered by a KVM bug. This is a sensible and safe change anyway, and the KVM bug fix might not be suitable for stable releases anyway. Signed-off-by:
Dirk Mueller <dmueller@suse.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com> Signed-off-by:
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Andy Lutomirski authored
commit 83c133cf upstream. The NMI entry code that switches to the normal kernel stack needs to be very careful not to clobber any extra stack slots on the NMI stack. The code is fine under the assumption that SWAPGS is just a normal instruction, but that assumption isn't really true. Use SWAPGS_UNSAFE_STACK instead. This is part of a fix for some random crashes that Sasha saw. Fixes: 9b6e6a83 ("x86/nmi/64: Switch stacks on userspace NMI entry") Reported-and-tested-by:
Sasha Levin <sasha.levin@oracle.com> Signed-off-by:
Andy Lutomirski <luto@kernel.org> Link: http://lkml.kernel.org/r/974bc40edffdb5c2950a5c4977f821a446b76178.1442791737.git.luto@kernel.orgSigned-off-by:
Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
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Andy Lutomirski authored
commit fc57a7c6 upstream. PARAVIRT_ADJUST_EXCEPTION_FRAME generates this code (using nmi as an example, trimmed for readability): ff 15 00 00 00 00 callq *0x0(%rip) # 2796 <nmi+0x6> 2792: R_X86_64_PC32 pv_irq_ops+0x2c That's a call through a function pointer to regular C function that does nothing on native boots, but that function isn't protected against kprobes, isn't marked notrace, and is certainly not guaranteed to preserve any registers if the compiler is feeling perverse. This is bad news for a CLBR_NONE operation. Of course, if everything works correctly, once paravirt ops are patched, it gets nopped out, but what if we hit this code before paravirt ops are patched in? This can potentially cause breakage that is very difficult to debug. A more subtle failure is possible here, too: if _paravirt_nop uses the stack at all (even just to push RBP), it will overwrite the "NMI executing" variable if it's called in the NMI prologue. The Xen case, perhaps surprisingly, is fine, because it's already written in asm. Fix all of the cases that default to paravirt_nop (including adjust_exception_frame) with a big hammer: replace paravirt_nop with an asm function that is just a ret instruction. The Xen case may have other problems, so document them. This is part of a fix for some random crashes that Sasha saw. Reported-and-tested-by:
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David Woodhouse authored
commit 03da3ff1 upstream. In 2007, commit 07190a08 ("Mark TSC on GeodeLX reliable") bypassed verification of the TSC on Geode LX. However, this code (now in the check_system_tsc_reliable() function in arch/x86/kernel/tsc.c) was only present if CONFIG_MGEODE_LX was set. OpenWRT has recently started building its generic Geode target for Geode GX, not LX, to include support for additional platforms. This broke the timekeeping on LX-based devices, because the TSC wasn't marked as reliable: https://dev.openwrt.org/ticket/20531 By adding a runtime check on is_geode_lx(), we can also include the fix if CONFIG_MGEODEGX1 or CONFIG_X86_GENERIC are set, thus fixing the problem. Signed-off-by:
David Woodhouse <David.Woodhouse@intel.com> Cc: Andres Salomon <dilinger@queued.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Marcelo Tosatti <marcelo@kvack.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1442409003.131189.87.camel@infradead.orgSigned-off-by:
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Shaohua Li authored
commit 5d7c631d upstream. The APIC LVTT register is MMIO mapped but the TSC_DEADLINE register is an MSR. The write to the TSC_DEADLINE MSR is not serializing, so it's not guaranteed that the write to LVTT has reached the APIC before the TSC_DEADLINE MSR is written. In such a case the write to the MSR is ignored and as a consequence the local timer interrupt never fires. The SDM decribes this issue for xAPIC and x2APIC modes. The serialization methods recommended by the SDM differ. xAPIC: "1. Memory-mapped write to LVT Timer Register, setting bits 18:17 to 10b. 2. WRMSR to the IA32_TSC_DEADLINE MSR a value much larger than current time-stamp counter. 3. If RDMSR of the IA32_TSC_DEADLINE MSR returns zero, go to step 2. 4. WRMSR to the IA32_TSC_DEADLINE MSR the desired deadline." x2APIC: "To allow for efficient access to the APIC registers in x2APIC mode, the serializing semantics of WRMSR are relaxed when writing to the APIC registers. Thus, system software should not use 'WRMSR to APIC registers in x2APIC mode' as a serializing instruction. Read and write accesses to the APIC registers will occur in program order. A WRMSR to an APIC register may complete before all preceding stores are globally visible; software can prevent this by inserting a serializing instruction, an SFENCE, or an MFENCE before the WRMSR." The xAPIC method is to just wait for the memory mapped write to hit the LVTT by checking whether the MSR write has reached the hardware. There is no reason why a proper MFENCE after the memory mapped write would not do the same. Andi Kleen confirmed that MFENCE is sufficient for the xAPIC case as well. Issue MFENCE before writing to the TSC_DEADLINE MSR. This can be done unconditionally as all CPUs which have TSC_DEADLINE also have MFENCE support. [ tglx: Massaged the changelog ] Signed-off-by:
Shaohua Li <shli@fb.com> Reviewed-by:
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Andy Shevchenko authored
commit 6bea0f6d upstream. In case we have less than maximum allowed channels (8) and autoconfiguration is enabled the DWC_PARAMS read is wrong because it uses different arithmetic to what is needed for channel priority setup. Re-do the caclulations properly. This now works on AVR32 board well. Fixes: fed2574b (dw_dmac: introduce software emulation of LLP transfers) Cc: yitian.bu@tangramtek.com Signed-off-by:
Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by:
Vinod Koul <vinod.koul@intel.com> Signed-off-by:
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Grazvydas Ignotas authored
commit 1dbdad75 upstream. The i2c5 pinctrl offsets are wrong. If the bootloader doesn't set the pins up, communication with tca6424a doesn't work (controller timeouts) and it is not possible to enable HDMI. Fixes: 9be495c4 ("ARM: dts: omap5-evm: Add I2c pinctrl data") Signed-off-by:
Grazvydas Ignotas <notasas@gmail.com> Signed-off-by:
Tony Lindgren <tony@atomide.com> Signed-off-by:
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Paul Bolle authored
commit fe2b5921 upstream. wf_unregister_client() increments the client count when a client unregisters. That is obviously incorrect. Decrement that client count instead. Fixes: 75722d39 ("[PATCH] ppc64: Thermal control for SMU based machines") Signed-off-by:
Paul Bolle <pebolle@tiscali.nl> Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Signed-off-by:
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Ard Biesheuvel authored
commit a077224f upstream. While working on the 32-bit ARM port of UEFI, I noticed a strange corruption in the kernel log. The following snprintf() statement (in drivers/firmware/efi/efi.c:efi_md_typeattr_format()) snprintf(pos, size, "|%3s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]", was producing the following output in the log: | | | | | |WB|WT|WC|UC] | | | | | |WB|WT|WC|UC] | | | | | |WB|WT|WC|UC] |RUN| | | | |WB|WT|WC|UC]* |RUN| | | | |WB|WT|WC|UC]* | | | | | |WB|WT|WC|UC] |RUN| | | | |WB|WT|WC|UC]* | | | | | |WB|WT|WC|UC] |RUN| | | | | | | |UC] |RUN| | | | | | | |UC] As it turns out, this is caused by incorrect code being emitted for the string() function in lib/vsprintf.c. The following code if (!(spec.flags & LEFT)) { while (len < spec.field_width--) { if (buf < end) *buf = ' '; ++buf; } } for (i = 0; i < len; ++i) { if (buf < end) *buf = *s; ++buf; ++s; } while (len < spec.field_width--) { if (buf < end) *buf = ' '; ++buf; } when called with len == 0, triggers an issue in the GCC SRA optimization pass (Scalar Replacement of Aggregates), which handles promotion of signed struct members incorrectly. This is a known but as yet unresolved issue. (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65932). In this particular case, it is causing the second while loop to be executed erroneously a single time, causing the additional space characters to be printed. So disable the optimization by passing -fno-ipa-sra. Acked-by:
Nicolas Pitre <nico@linaro.org> Signed-off-by:
Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by:
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Russell King authored
commit 9b55613f upstream. When a kernel is built covering ARMv6 to ARMv7, we omit to clear the IT state when entering a signal handler. This can cause the first few instructions to be conditionally executed depending on the parent context. In any case, the original test for >= ARMv7 is broken - ARMv6 can have Thumb-2 support as well, and an ARMv6T2 specific build would omit this code too. Relax the test back to ARMv6 or greater. This results in us always clearing the IT state bits in the PSR, even on CPUs where these bits are reserved. However, they're reserved for the IT state, so this should cause no harm. Fixes: d71e1352 ("Clear the IT state when invoking a Thumb-2 signal handler") Acked-by:
H. Nikolaus Schaller <hns@goldelico.com> Tested-by:
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Guenter Roeck authored
commit 728d2940 upstream. The STEP_UP_TIME and STEP_DOWN_TIME registers are swapped for all chips but NCT6775. Reported-by:
Jean Delvare <jdelvare@suse.de> Signed-off-by:
Guenter Roeck <linux@roeck-us.net> Signed-off-by:
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Arnaldo Carvalho de Melo authored
commit caa47047 upstream. The original patch introducing this header wrote the number of CPUs available and online in one order and then swapped those values when reading, fix it. Before: # perf record usleep 1 # perf report --header-only | grep 'nrcpus \(online\|avail\)' # nrcpus online : 4 # nrcpus avail : 4 # echo 0 > /sys/devices/system/cpu/cpu2/online # perf record usleep 1 # perf report --header-only | grep 'nrcpus \(online\|avail\)' # nrcpus online : 4 # nrcpus avail : 3 # echo 0 > /sys/devices/system/cpu/cpu1/online # perf record usleep 1 # perf report --header-only | grep 'nrcpus \(online\|avail\)' # nrcpus online : 4 # nrcpus avail : 2 After the fix, bringing back the CPUs online: # perf report --header-only | grep 'nrcpus \(online\|avail\)' # nrcpus online : 2 # nrcpus avail : 4 # echo 1 > /sys/devices/system/cpu/cpu2/online # perf record usleep 1 # perf report --header-only | grep 'nrcpus \(online\|avail\)' # nrcpus online : 3 # nrcpus avail : 4 # echo 1 > /sys/devices/system/cpu/cpu1/online # perf record usleep 1 # perf report --header-only | grep 'nrcpus \(online\|avail\)' # nrcpus online : 4 # nrcpus avail : 4 Acked-by:
Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Stephane Eranian <eranian@google.com> Cc: Wang Nan <wangnan0@huawei.com> Fixes: fbe96f29 ("perf tools: Make perf.data more self-descriptive (v8)") Link: http://lkml.kernel.org/r/20150911153323.GP23511@kernel.orgSigned-off-by:
Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by:
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Kan Liang authored
commit 601083cf upstream. print_aggr() fails to print per-core/per-socket statistics after commit 582ec082 ("perf stat: Fix per-socket output bug for uncore events") if events have differnt cpus. Because in print_aggr(), aggr_get_id needs index (not cpu id) to find core/pkg id. Also, evsel cpu maps should be used to get aggregated id. Here is an example: Counting events cycles,uncore_imc_0/cas_count_read/. (Uncore event has cpumask 0,18) $ perf stat -e cycles,uncore_imc_0/cas_count_read/ -C0,18 --per-core sleep 2 Without this patch, it failes to get CPU 18 result. Performance counter stats for 'CPU(s) 0,18': S0-C0 1 7526851 cycles S0-C0 1 1.05 MiB uncore_imc_0/cas_count_read/ S1-C0 0 <not counted> cycles S1-C0 0 <not counted> MiB uncore_imc_0/cas_count_read/ With this patch, it can get both CPU0 and CPU18 result. Performance counter stats for 'CPU(s) 0,18': S0-C0 1 6327768 cycles S0-C0 1 0.47 MiB uncore_imc_0/cas_count_read/ S1-C0 1 330228 cycles S1-C0 1 0.29 MiB uncore_imc_0/cas_count_read/ Signed-off-by:
Kan Liang <kan.liang@intel.com> Acked-by:
Jiri Olsa <jolsa@kernel.org> Acked-by:
Stephane Eranian <eranian@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Fixes: 582ec082 ("perf stat: Fix per-socket output bug for uncore events") Link: http://lkml.kernel.org/r/1435820925-51091-1-git-send-email-kan.liang@intel.comSigned-off-by:
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Arnaldo Carvalho de Melo authored
commit e8e6d37e upstream. When we introduce a new sort key, we need to update the hists__calc_col_len() function accordingly, otherwise the width will be limited to strlen(header). We can't update it when obtaining a line value for a column (for instance, in sort__srcline_cmp()), because we reset it all when doing a resort (see hists__output_recalc_col_len()), so we need to, from what is in the hist_entry fields, set each of the column widths. Cc: Namhyung Kim <namhyung@kernel.org> Cc: Andi Kleen <andi@firstfloor.org> Cc: Jiri Olsa <jolsa@kernel.org> Fixes: 409a8be6 ("perf tools: Add sort by src line/number") Link: http://lkml.kernel.org/n/tip-jgbe0yx8v1gs89cslr93pvz2@git.kernel.orgSigned-off-by:
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Adrian Hunter authored
commit b5cabbcb upstream. A copy of /proc/kcore containing the kernel text can be made to the buildid cache. e.g. perf buildid-cache -v -k /proc/kcore To workaround objdump limitations, a copy is also made when annotating against /proc/kcore. The copying process stops working from libelf about v1.62 onwards (the problem was found with v1.63). The cause is that a call to gelf_getphdr() in kcore__add_phdr() fails because additional validation has been added to gelf_getphdr(). The use of gelf_getphdr() is a misguided attempt to get default initialization of the Gelf_Phdr structure. That should not be necessary because every member of the Gelf_Phdr structure is subsequently assigned. So just remove the call to gelf_getphdr(). Similarly, a call to gelf_getehdr() in gelf_kcore__init() can be removed also. Committer notes: Note to stable@kernel.org, from Adrian in the cover letter for this patchkit: The "Fix copying of /proc/kcore" problem goes back to v3.13 if you think it is important enough for stable. Signed-off-by:
Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/1443089122-19082-3-git-send-email-adrian.hunter@intel.comSigned-off-by:
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Jenny Derzhavetz authored
commit a4c15cd9 upstream. As documented in iscsit_sequence_cmd: /* * Existing callers for iscsit_sequence_cmd() will silently * ignore commands with CMDSN_LOWER_THAN_EXP, so force this * return for CMDSN_MAXCMDSN_OVERRUN as well.. */ We need to silently finish a command when it's in ISTATE_REMOVE. This fixes an teardown hang we were seeing where a mis-behaved initiator (triggered by allocation error injections) sent us a cmdsn which was lower than expected. Signed-off-by:
Jenny Derzhavetz <jennyf@mellanox.com> Signed-off-by:
Sagi Grimberg <sagig@mellanox.com> Signed-off-by:
Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by:
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Michal Hocko authored
commit 537b604c upstream. b9d5c6b7 ("[SCSI] cleanup setting task state in scsi_error_handler()") has introduced a race between scsi_error_handler and scsi_host_dev_release resulting in the hang when the device goes away because scsi_error_handler might miss a wake up: CPU0 CPU1 scsi_error_handler scsi_host_dev_release kthread_stop() kthread_should_stop() test_bit(KTHREAD_SHOULD_STOP) set_bit(KTHREAD_SHOULD_STOP) wake_up_process() wait_for_completion() set_current_state(TASK_INTERRUPTIBLE) schedule() The most straightforward solution seems to be to invert the ordering of the set_current_state and kthread_should_stop. The issue has been noticed during reboot test on a 3.0 based kernel but the current code seems to be affected in the same way. [jejb: additional comment added] Reported-and-debugged-by:
Mike Mayer <Mike.Meyer@teradata.com> Signed-off-by:
Michal Hocko <mhocko@suse.com> Reviewed-by:
Dan Williams <dan.j.williams@intel.com> Reviewed-by:
Hannes Reinecke <hare@suse.de> Signed-off-by:
James Bottomley <JBottomley@Odin.com> Signed-off-by:
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Jason Wang authored
commit 8f4216c7 upstream. Currently, if we had a zero length mmio eventfd assigned on KVM_MMIO_BUS. It will never be found by kvm_io_bus_cmp() since it always compares the kvm_io_range() with the length that guest wrote. This will cause e.g for vhost, kick will be trapped by qemu userspace instead of vhost. Fixing this by using zero length if an iodevice is zero length. Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by:
Jason Wang <jasowang@redhat.com> Reviewed-by:
Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by:
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- 01 Oct, 2015 21 commits
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Greg Kroah-Hartman authored
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Keith Busch authored
commit fb35e914 upstream. If an NVMe device becomes ready but fails to create IO queues, the driver creates a character device handle so the device can be managed. The device reference count needs to be initialized before creating the character device. Signed-off-by:
Keith Busch <keith.busch@intel.com> Signed-off-by:
Matthew Wilcox <matthew.r.wilcox@intel.com> Signed-off-by:
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Jan Kara authored
commit 23b133bd upstream. Check length of extended attributes and allocation descriptors when loading inodes from disk. Otherwise corrupted filesystems could confuse the code and make the kernel oops. This fixes CVE-2015-4167. Reported-by:
Carl Henrik Lunde <chlunde@ping.uio.no> Signed-off-by:
Jan Kara <jack@suse.cz> [Use make_bad_inode() instead of branching due to older implementation.] Signed-off-by:
Chas Williams <3chas3@gmail.com> Signed-off-by:
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Andy Lutomirski authored
commit 810bc075 upstream. We have a tricky bug in the nested NMI code: if we see RSP pointing to the NMI stack on NMI entry from kernel mode, we assume that we are executing a nested NMI. This isn't quite true. A malicious userspace program can point RSP at the NMI stack, issue SYSCALL, and arrange for an NMI to happen while RSP is still pointing at the NMI stack. Fix it with a sneaky trick. Set DF in the region of code that the RSP check is intended to detect. IRET will clear DF atomically. ( Note: other than paravirt, there's little need for all this complexity. We could check RIP instead of RSP. ) Signed-off-by:
Steven Rostedt <rostedt@goodmis.org> Cc: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
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Andy Lutomirski authored
commit a27507ca upstream. Check the repeat_nmi .. end_repeat_nmi special case first. The next patch will rework the RSP check and, as a side effect, the RSP check will no longer detect repeat_nmi .. end_repeat_nmi, so we'll need this ordering of the checks. Note: this is more subtle than it appears. The check for repeat_nmi .. end_repeat_nmi jumps straight out of the NMI code instead of adjusting the "iret" frame to force a repeat. This is necessary, because the code between repeat_nmi and end_repeat_nmi sets "NMI executing" and then writes to the "iret" frame itself. If a nested NMI comes in and modifies the "iret" frame while repeat_nmi is also modifying it, we'll end up with garbage. The old code got this right, as does the new code, but the new code is a bit more explicit. If we were to move the check right after the "NMI executing" check, then we'd get it wrong and have random crashes. ( Because the "NMI executing" check would jump to the code that would modify the "iret" frame without checking if the interrupted NMI was currently modifying it. ) Signed-off-by:
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Andy Lutomirski authored
commit 0b22930e upstream. I found the nested NMI documentation to be difficult to follow. Improve the comments. Signed-off-by:
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Andy Lutomirski authored
commit 9b6e6a83 upstream. Returning to userspace is tricky: IRET can fail, and ESPFIX can rearrange the stack prior to IRET. The NMI nesting fixup relies on a precise stack layout and atomic IRET. Rather than trying to teach the NMI nesting fixup to handle ESPFIX and failed IRET, punt: run NMIs that came from user mode on the normal kernel stack. This will make some nested NMIs visible to C code, but the C code is okay with that. As a side effect, this should speed up perf: it eliminates an RDMSR when NMIs come from user mode. Signed-off-by:
Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Signed-off-by:
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Andy Lutomirski authored
commit 0e181bb5 upstream. Now that do_nmi saves CR2, we don't need to save it in asm. Signed-off-by:
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Andy Lutomirski authored
commit 9d050416 upstream. 32-bit kernels handle nested NMIs in C. Enable the exact same handling on 64-bit kernels as well. This isn't currently necessary, but it will become necessary once the asm code starts allowing limited nesting. Signed-off-by:
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Markus Pargmann authored
This reverts commit 279c039c which was commit 06d2f6ca upstream as it should not have been applied. Reported-by:
Luis Henriques <luis.henriques@canonical.com> Cc: Markus Pargmann <mpa@pengutronix.de> Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Cc: Jonathan Cameron <jic23@kernel.org> Signed-off-by:
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Florian Westphal authored
[ Upstream commit 1e16aa3d ] skb_gso_segment() has a 'features' argument representing offload features available to the output path. A few handlers, e.g. GRE, instead re-fetch the features of skb->dev and use those instead of the provided ones when handing encapsulation/tunnels. Depending on dev->hw_enc_features of the output device skb_gso_segment() can then return NULL even when the caller has disabled all GSO feature bits, as segmentation of inner header thinks device will take care of segmentation. This e.g. affects the tbf scheduler, which will silently drop GRE-encap GSO skbs that did not fit the remaining token quota as the segmentation does not work when device supports corresponding hw offload capabilities. Cc: Pravin B Shelar <pshelar@nicira.com> Signed-off-by:
Florian Westphal <fw@strlen.de> Signed-off-by:
David S. Miller <davem@davemloft.net> [jay.vosburgh: backported to 3.14. ] Signed-off-by:
Jay Vosburgh <jay.vosburgh@canonical.com> Signed-off-by:
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Ivan Vecera authored
[ Upstream commit ade4dc3e ] The commit "e29aa339 bna: Enable Multi Buffer RX" moved packets counter increment from the beginning of the NAPI processing loop after the check for erroneous packets so they are never accounted. This counter is used to inform firmware about number of processed completions (packets). As these packets are never acked the firmware fires IRQs for them again and again. Fixes: e29aa339 ("bna: Enable Multi Buffer RX") Signed-off-by:
Ivan Vecera <ivecera@redhat.com> Acked-by:
Rasesh Mody <rasesh.mody@qlogic.com> Signed-off-by:
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Eric Dumazet authored
[ Upstream commit 10e2eb87 ] Multicast dst are not cached. They carry DST_NOCACHE. As mentioned in commit f8864972 ("ipv4: fix dst race in sk_dst_get()"), these dst need special care before caching them into a socket. Caching them is allowed only if their refcnt was not 0, ie we must use atomic_inc_not_zero() Also, we must use READ_ONCE() to fetch sk->sk_rx_dst, as mentioned in commit d0c294c5 ("tcp: prevent fetching dst twice in early demux code") Fixes: 421b3885 ("udp: ipv4: Add udp early demux") Tested-by:
Gregory Hoggarth <Gregory.Hoggarth@alliedtelesis.co.nz> Signed-off-by:
Eric Dumazet <edumazet@google.com> Reported-by:
Alex Gartrell <agartrell@fb.com> Cc: Michal Kubeček <mkubecek@suse.cz> Signed-off-by:
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Dan Carpenter authored
[ Upstream commit 468b732b ] "len" is a signed integer. We check that len is not negative, so it goes from zero to INT_MAX. PAGE_SIZE is unsigned long so the comparison is type promoted to unsigned long. ULONG_MAX - 4095 is a higher than INT_MAX so the condition can never be true. I don't know if this is harmful but it seems safe to limit "len" to INT_MAX - 4095. Fixes: a8c879a7 ('RDS: Info and stats') Signed-off-by:
Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by:
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Lars Westerhoff authored
[ Upstream commit 158cd4af ] When binding a PF_PACKET socket, the use count of the bound interface is always increased with dev_hold in dev_get_by_{index,name}. However, when rebound with the same protocol and device as in the previous bind the use count of the interface was not decreased. Ultimately, this caused the deletion of the interface to fail with the following message: unregister_netdevice: waiting for dummy0 to become free. Usage count = 1 This patch moves the dev_put out of the conditional part that was only executed when either the protocol or device changed on a bind. Fixes: 902fefb8 ('packet: improve socket create/bind latency in some cases') Signed-off-by:
Lars Westerhoff <lars.westerhoff@newtec.eu> Signed-off-by:
Daniel Borkmann <dborkman@redhat.com> Signed-off-by:
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Wilson Kok authored
[ Upstream commit 41fc0143 ] dump_rules returns skb length and not error. But when family == AF_UNSPEC, the caller of dump_rules assumes that it returns an error. Hence, when family == AF_UNSPEC, we continue trying to dump on -EMSGSIZE errors resulting in incorrect dump idx carried between skbs belonging to the same dump. This results in fib rule dump always only dumping rules that fit into the first skb. This patch fixes dump_rules to return error so that we exit correctly and idx is correctly maintained between skbs that are part of the same dump. Signed-off-by:
Wilson Kok <wkok@cumulusnetworks.com> Signed-off-by:
Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by:
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Jesse Gross authored
[ Upstream commit ae5f2fb1 ] When support for megaflows was introduced, OVS needed to start installing flows with a mask applied to them. Since masking is an expensive operation, OVS also had an optimization that would only take the parts of the flow keys that were covered by a non-zero mask. The values stored in the remaining pieces should not matter because they are masked out. While this works fine for the purposes of matching (which must always look at the mask), serialization to netlink can be problematic. Since the flow and the mask are serialized separately, the uninitialized portions of the flow can be encoded with whatever values happen to be present. In terms of functionality, this has little effect since these fields will be masked out by definition. However, it leaks kernel memory to userspace, which is a potential security vulnerability. It is also possible that other code paths could look at the masked key and get uninitialized data, although this does not currently appear to be an issue in practice. This removes the mask optimization for flows that are being installed. This was always intended to be the case as the mask optimizations were really targetting per-packet flow operations. Fixes: 03f0d916 ("openvswitch: Mega flow implementation") Signed-off-by:
Jesse Gross <jesse@nicira.com> Acked-by:
Pravin B Shelar <pshelar@nicira.com> Signed-off-by:
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Marcelo Ricardo Leitner authored
[ Upstream commit 8e2d61e0 ] Consider sctp module is unloaded and is being requested because an user is creating a sctp socket. During initialization, sctp will add the new protocol type and then initialize pernet subsys: status = sctp_v4_protosw_init(); if (status) goto err_protosw_init; status = sctp_v6_protosw_init(); if (status) goto err_v6_protosw_init; status = register_pernet_subsys(&sctp_net_ops); The problem is that after those calls to sctp_v{4,6}_protosw_init(), it is possible for userspace to create SCTP sockets like if the module is already fully loaded. If that happens, one of the possible effects is that we will have readers for net->sctp.local_addr_list list earlier than expected and sctp_net_init() does not take precautions while dealing with that list, leading to a potential panic but not limited to that, as sctp_sock_init() will copy a bunch of blank/partially initialized values from net->sctp. The race happens like this: CPU 0 | CPU 1 socket() | __sock_create | socket() inet_create | __sock_create list_for_each_entry_rcu( | answer, &inetsw[sock->type], | list) { | inet_create /* no hits */ | if (unlikely(err)) { | ... | request_module() | /* socket creation is blocked | * the module is fully loaded | */ | sctp_init | sctp_v4_protosw_init | inet_register_protosw | list_add_rcu(&p->list, | last_perm); | | list_for_each_entry_rcu( | answer, &inetsw[sock->type], sctp_v6_protosw_init | list) { | /* hit, so assumes protocol | * is already loaded | */ | /* socket creation continues | * before netns is initialized | */ register_pernet_subsys | Simply inverting the initialization order between register_pernet_subsys() and sctp_v4_protosw_init() is not possible because register_pernet_subsys() will create a control sctp socket, so the protocol must be already visible by then. Deferring the socket creation to a work-queue is not good specially because we loose the ability to handle its errors. So, as suggested by Vlad, the fix is to split netns initialization in two moments: defaults and control socket, so that the defaults are already loaded by when we register the protocol, while control socket initialization is kept at the same moment it is today. Fixes: 4db67e80 ("sctp: Make the address lists per network namespace") Signed-off-by:
Vlad Yasevich <vyasevich@gmail.com> Signed-off-by:
Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by:
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Daniel Borkmann authored
[ Upstream commit 1853c949 ] Ken-ichirou reported that running netlink in mmap mode for receive in combination with nlmon will throw a NULL pointer dereference in __kfree_skb() on nlmon_xmit(), in my case I can also trigger an "unable to handle kernel paging request". The problem is the skb_clone() in __netlink_deliver_tap_skb() for skbs that are mmaped. I.e. the cloned skb doesn't have a destructor, whereas the mmap netlink skb has it pointed to netlink_skb_destructor(), set in the handler netlink_ring_setup_skb(). There, skb->head is being set to NULL, so that in such cases, __kfree_skb() doesn't perform a skb_release_data() via skb_release_all(), where skb->head is possibly being freed through kfree(head) into slab allocator, although netlink mmap skb->head points to the mmap buffer. Similarly, the same has to be done also for large netlink skbs where the data area is vmalloced. Therefore, as discussed, make a copy for these rather rare cases for now. This fixes the issue on my and Ken-ichirou's test-cases. Reference: http://thread.gmane.org/gmane.linux.network/371129 Fixes: bcbde0d4 ("net: netlink: virtual tap device management") Reported-by:
Ken-ichirou MATSUZAWA <chamaken@gmail.com> Signed-off-by:
Daniel Borkmann <daniel@iogearbox.net> Tested-by:
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Richard Laing authored
[ Upstream commit 25b4a44c ] In the IPv6 multicast routing code the mrt_lock was not being released correctly in the MFC iterator, as a result adding or deleting a MIF would cause a hang because the mrt_lock could not be acquired. This fix is a copy of the code for the IPv4 case and ensures that the lock is released correctly. Signed-off-by:
Richard Laing <richard.laing@alliedtelesis.co.nz> Acked-by:
Cong Wang <cwang@twopensource.com> Signed-off-by:
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Daniel Borkmann authored
[ Upstream commit e41b0bed ] We previously register IPPROTO_ROUTING offload under inet6_add_offload(), but in error path, we try to unregister it with inet_del_offload(). This doesn't seem correct, it should actually be inet6_del_offload(), also ipv6_exthdrs_offload_exit() from that commit seems rather incorrect (it also uses rthdr_offload twice), but it got removed entirely later on. Fixes: 3336288a ("ipv6: Switch to using new offload infrastructure.") Signed-off-by:
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