kernel/linux.git/arch, branch v4.12.9

debug: Fix WARN_ON_ONCE() for modules

2017-08-25T00:15:05+00:00

commit 325cdacd03c12629aa5f9ee2ace49b1f3dc184a8 upstream. Mike Galbraith reported a situation where a WARN_ON_ONCE() call in DRM code turned into an oops. As it turns out, WARN_ON_ONCE() seems to be completely broken when called from a module. The bug was introduced with the following commit: 19d436268dde ("debug: Add _ONCE() logic to report_bug()") That commit changed WARN_ON_ONCE() to move its 'once' logic into the bug trap handler. It requires a writable bug table so that the BUGFLAG_DONE bit can be written to the flags to indicate the first warning has occurred. The bug table was made writable for vmlinux, which relies on vmlinux.lds.S and vmlinux.lds.h for laying out the sections. However, it wasn't made writable for modules, which rely on the ELF section header flags. Reported-by: Mike Galbraith Tested-by: Masami Hiramatsu Signed-off-by: Josh Poimboeuf Acked-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: 19d436268dde ("debug: Add _ONCE() logic to report_bug()") Link: http://lkml.kernel.org/r/a53b04235a65478dd9afc51f5b329fdc65c84364.1500095401.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar Signed-off-by: Changbin Du Signed-off-by: Greg Kroah-Hartman

kernel/watchdog: Prevent false positives with turbo modes

2017-08-25T00:15:04+00:00

commit 7edaeb6841dfb27e362288ab8466ebdc4972e867 upstream. The hardlockup detector on x86 uses a performance counter based on unhalted CPU cycles and a periodic hrtimer. The hrtimer period is about 2/5 of the performance counter period, so the hrtimer should fire 2-3 times before the performance counter NMI fires. The NMI code checks whether the hrtimer fired since the last invocation. If not, it assumess a hard lockup. The calculation of those periods is based on the nominal CPU frequency. Turbo modes increase the CPU clock frequency and therefore shorten the period of the perf/NMI watchdog. With extreme Turbo-modes (3x nominal frequency) the perf/NMI period is shorter than the hrtimer period which leads to false positives. A simple fix would be to shorten the hrtimer period, but that comes with the side effect of more frequent hrtimer and softlockup thread wakeups, which is not desired. Implement a low pass filter, which checks the perf/NMI period against kernel time. If the perf/NMI fires before 4/5 of the watchdog period has elapsed then the event is ignored and postponed to the next perf/NMI. That solves the problem and avoids the overhead of shorter hrtimer periods and more frequent softlockup thread wakeups. Fixes: 58687acba592 ("lockup_detector: Combine nmi_watchdog and softlockup detector") Reported-and-tested-by: Kan Liang Signed-off-by: Thomas Gleixner Cc: dzickus@redhat.com Cc: prarit@redhat.com Cc: ak@linux.intel.com Cc: babu.moger@oracle.com Cc: peterz@infradead.org Cc: eranian@google.com Cc: acme@redhat.com Cc: atomlin@redhat.com Cc: akpm@linux-foundation.org Cc: torvalds@linux-foundation.org Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1708150931310.1886@nanos Signed-off-by: Greg Kroah-Hartman

x86/elf: Remove the unnecessary ADDR_NO_RANDOMIZE checks

2017-08-25T00:15:04+00:00

commit 01578e36163cdd0e4fd61d9976de15f13364e26d upstream. The ADDR_NO_RANDOMIZE checks in stack_maxrandom_size() and randomize_stack_top() are not required. PF_RANDOMIZE is set by load_elf_binary() only if ADDR_NO_RANDOMIZE is not set, no need to re-check after that. Signed-off-by: Oleg Nesterov Signed-off-by: Thomas Gleixner Reviewed-by: Dmitry Safonov Cc: Andy Lutomirski Cc: Andrew Morton Cc: Borislav Petkov Cc: Linus Torvalds Cc: "Kirill A. Shutemov" Link: http://lkml.kernel.org/r/20170815154011.GB1076@redhat.com Signed-off-by: Greg Kroah-Hartman

x86: Fix norandmaps/ADDR_NO_RANDOMIZE

2017-08-25T00:15:03+00:00

commit 47ac5484fd961420e5ec0bb5b972fde381f57365 upstream. Documentation/admin-guide/kernel-parameters.txt says: norandmaps Don't use address space randomization. Equivalent to echo 0 > /proc/sys/kernel/randomize_va_space but it doesn't work because arch_rnd() which is used to randomize mm->mmap_base returns a random value unconditionally. And as Kirill pointed out, ADDR_NO_RANDOMIZE is broken by the same reason. Just shift the PF_RANDOMIZE check from arch_mmap_rnd() to arch_rnd(). Fixes: 1b028f784e8c ("x86/mm: Introduce mmap_compat_base() for 32-bit mmap()") Signed-off-by: Oleg Nesterov Signed-off-by: Thomas Gleixner Acked-by: Kirill A. Shutemov Acked-by: Cyrill Gorcunov Reviewed-by: Dmitry Safonov Cc: Andy Lutomirski Cc: Andrew Morton Cc: Borislav Petkov Cc: Linus Torvalds Link: http://lkml.kernel.org/r/20170815153952.GA1076@redhat.com Signed-off-by: Greg Kroah-Hartman

x86/asm/64: Clear AC on NMI entries

2017-08-25T00:15:03+00:00

commit e93c17301ac55321fc18e0f8316e924e58a83c8c upstream. This closes a hole in our SMAP implementation. This patch comes from grsecurity. Good catch! Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/314cc9f294e8f14ed85485727556ad4f15bb1659.1502159503.git.luto@kernel.org Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

perf/x86: Fix RDPMC vs. mm_struct tracking

2017-08-25T00:15:03+00:00

commit bfe334924ccd9f4a53f30240c03cf2f43f5b2df1 upstream. Vince reported the following rdpmc() testcase failure: > Failing test case: > > fd=perf_event_open(); > addr=mmap(fd); > exec() // without closing or unmapping the event > fd=perf_event_open(); > addr=mmap(fd); > rdpmc() // GPFs due to rdpmc being disabled The problem is of course that exec() plays tricks with what is current->mm, only destroying the old mappings after having installed the new mm. Fix this confusion by passing along vma->vm_mm instead of relying on current->mm. Reported-by: Vince Weaver Tested-by: Vince Weaver Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Andy Lutomirski Cc: Arnaldo Carvalho de Melo Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Fixes: 1e0fb9ec679c ("perf: Add pmu callbacks to track event mapping and unmapping") Link: http://lkml.kernel.org/r/20170802173930.cstykcqefmqt7jau@hirez.programming.kicks-ass.net [ Minor cleanups. ] Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

powerpc: Fix VSX enabling/flushing to also test MSR_FP and MSR_VEC

2017-08-25T00:15:03+00:00

commit 5a69aec945d27e78abac9fd032533d3aaebf7c1e upstream. VSX uses a combination of the old vector registers, the old FP registers and new "second halves" of the FP registers. Thus when we need to see the VSX state in the thread struct (flush_vsx_to_thread()) or when we'll use the VSX in the kernel (enable_kernel_vsx()) we need to ensure they are all flushed into the thread struct if either of them is individually enabled. Unfortunately we only tested if the whole VSX was enabled, not if they were individually enabled. Fixes: 72cd7b44bc99 ("powerpc: Uncomment and make enable_kernel_vsx() routine available") Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman

ARM: dts: imx6qdl-nitrogen6_som2: fix PCIe reset

2017-08-25T00:15:03+00:00

commit c40bc54fdf2d52a80f66b365f1eac9d43b32e107 upstream. Previous value was a bad copy of nitrogen6_max device tree. Signed-off-by: Gary Bisson Fixes: 3faa1bb2e89c ("ARM: dts: imx: add Boundary Devices Nitrogen6_SOM2 support") Signed-off-by: Shawn Guo Signed-off-by: Greg Kroah-Hartman

mm: revert x86_64 and arm64 ELF_ET_DYN_BASE base changes

2017-08-25T00:15:03+00:00

commit c715b72c1ba406f133217b509044c38d8e714a37 upstream. Moving the x86_64 and arm64 PIE base from 0x555555554000 to 0x000100000000 broke AddressSanitizer. This is a partial revert of: eab09532d400 ("binfmt_elf: use ELF_ET_DYN_BASE only for PIE") 02445990a96e ("arm64: move ELF_ET_DYN_BASE to 4GB / 4MB") The AddressSanitizer tool has hard-coded expectations about where executable mappings are loaded. The motivation for changing the PIE base in the above commits was to avoid the Stack-Clash CVEs that allowed executable mappings to get too close to heap and stack. This was mainly a problem on 32-bit, but the 64-bit bases were moved too, in an effort to proactively protect those systems (proofs of concept do exist that show 64-bit collisions, but other recent changes to fix stack accounting and setuid behaviors will minimize the impact). The new 32-bit PIE base is fine for ASan (since it matches the ET_EXEC base), so only the 64-bit PIE base needs to be reverted to let x86 and arm64 ASan binaries run again. Future changes to the 64-bit PIE base on these architectures can be made optional once a more dynamic method for dealing with AddressSanitizer is found. (e.g. always loading PIE into the mmap region for marked binaries.) Link: http://lkml.kernel.org/r/20170807201542.GA21271@beast Fixes: eab09532d400 ("binfmt_elf: use ELF_ET_DYN_BASE only for PIE") Fixes: 02445990a96e ("arm64: move ELF_ET_DYN_BASE to 4GB / 4MB") Signed-off-by: Kees Cook Reported-by: Kostya Serebryany Acked-by: Will Deacon Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

crypto: x86/sha1 - Fix reads beyond the number of blocks passed

2017-08-25T00:15:01+00:00

commit 8861249c740fc4af9ddc5aee321eafefb960d7c6 upstream. It was reported that the sha1 AVX2 function(sha1_transform_avx2) is reading ahead beyond its intended data, and causing a crash if the next block is beyond page boundary: http://marc.info/?l=linux-crypto-vger&m=149373371023377 This patch makes sure that there is no overflow for any buffer length. It passes the tests written by Jan Stancek that revealed this problem: https://github.com/jstancek/sha1-avx2-crash I have re-enabled sha1-avx2 by reverting commit b82ce24426a4071da9529d726057e4e642948667 Fixes: b82ce24426a4 ("crypto: sha1-ssse3 - Disable avx2") Originally-by: Ilya Albrekht Tested-by: Jan Stancek Signed-off-by: Megha Dey Reported-by: Jan Stancek Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman