kernel/linux.git/init/main.c, branch v4.14.152

init: initialize jump labels before command line option parsing

2019-05-16T17:42:23+00:00

[ Upstream commit 6041186a32585fc7a1d0f6cfe2f138b05fdc3c82 ] When a module option, or core kernel argument, toggles a static-key it requires jump labels to be initialized early. While x86, PowerPC, and ARM64 arrange for jump_label_init() to be called before parse_args(), ARM does not. Kernel command line: rdinit=/sbin/init page_alloc.shuffle=1 panic=-1 console=ttyAMA0,115200 page_alloc.shuffle=1 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at ./include/linux/jump_label.h:303 page_alloc_shuffle+0x12c/0x1ac static_key_enable(): static key 'page_alloc_shuffle_key+0x0/0x4' used before call to jump_label_init() Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 5.1.0-rc4-next-20190410-00003-g3367c36ce744 #1 Hardware name: ARM Integrator/CP (Device Tree) [] (unwind_backtrace) from [] (show_stack+0x10/0x18) [] (show_stack) from [] (dump_stack+0x18/0x24) [] (dump_stack) from [] (__warn+0xe0/0x108) [] (__warn) from [] (warn_slowpath_fmt+0x44/0x6c) [] (warn_slowpath_fmt) from [] (page_alloc_shuffle+0x12c/0x1ac) [] (page_alloc_shuffle) from [] (shuffle_store+0x28/0x48) [] (shuffle_store) from [] (parse_args+0x1f4/0x350) [] (parse_args) from [] (start_kernel+0x1c0/0x488) Move the fallback call to jump_label_init() to occur before parse_args(). The redundant calls to jump_label_init() in other archs are left intact in case they have static key toggling use cases that are even earlier than option parsing. Link: http://lkml.kernel.org/r/155544804466.1032396.13418949511615676665.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Reported-by: Guenter Roeck Reviewed-by: Kees Cook Cc: Mathieu Desnoyers Cc: Thomas Gleixner Cc: Mike Rapoport Cc: Russell King Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

Revert "mm: use early_pfn_to_nid in page_ext_init"

2019-03-23T13:35:13+00:00

[ Upstream commit 2f1ee0913ce58efe7f18fbd518bd54c598559b89 ] This reverts commit fe53ca54270a ("mm: use early_pfn_to_nid in page_ext_init"). When booting a system with "page_owner=on", start_kernel page_ext_init invoke_init_callbacks init_section_page_ext init_page_owner init_early_allocated_pages init_zones_in_node init_pages_in_zone lookup_page_ext page_to_nid The issue here is that page_to_nid() will not work since some page flags have no node information until later in page_alloc_init_late() due to DEFERRED_STRUCT_PAGE_INIT. Hence, it could trigger an out-of-bounds access with an invalid nid. UBSAN: Undefined behaviour in ./include/linux/mm.h:1104:50 index 7 is out of range for type 'zone [5]' Also, kernel will panic since flags were poisoned earlier with, CONFIG_DEBUG_VM_PGFLAGS=y CONFIG_NODE_NOT_IN_PAGE_FLAGS=n start_kernel setup_arch pagetable_init paging_init sparse_init sparse_init_nid memblock_alloc_try_nid_raw It did not handle it well in init_pages_in_zone() which ends up calling page_to_nid(). page:ffffea0004200000 is uninitialized and poisoned raw: ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff raw: ffffffffffffffff ffffffffffffffff ffffffffffffffff ffffffffffffffff page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p)) page_owner info is not active (free page?) kernel BUG at include/linux/mm.h:990! RIP: 0010:init_page_owner+0x486/0x520 This means that assumptions behind commit fe53ca54270a ("mm: use early_pfn_to_nid in page_ext_init") are incomplete. Therefore, revert the commit for now. A proper way to move the page_owner initialization to sooner is to hook into memmap initialization. Link: http://lkml.kernel.org/r/20190115202812.75820-1-cai@lca.pw Signed-off-by: Qian Cai Acked-by: Michal Hocko Cc: Pasha Tatashin Cc: Mel Gorman Cc: Yang Shi Cc: Joonsoo Kim Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

init: rename and re-order boot_cpu_state_init()

2018-08-15T16:12:48+00:00

commit b5b1404d0815894de0690de8a1ab58269e56eae6 upstream. This is purely a preparatory patch for upcoming changes during the 4.19 merge window. We have a function called "boot_cpu_state_init()" that isn't really about the bootup cpu state: that is done much earlier by the similarly named "boot_cpu_init()" (note lack of "state" in name). This function initializes some hotplug CPU state, and needs to run after the percpu data has been properly initialized. It even has a comment to that effect. Except it _doesn't_ actually run after the percpu data has been properly initialized. On x86 it happens to do that, but on at least arm and arm64, the percpu base pointers are initialized by the arch-specific 'smp_prepare_boot_cpu()' hook, which ran _after_ boot_cpu_state_init(). This had some unexpected results, and in particular we have a patch pending for the merge window that did the obvious cleanup of using 'this_cpu_write()' in the cpu hotplug init code: - per_cpu_ptr(&cpuhp_state, smp_processor_id())->state = CPUHP_ONLINE; + this_cpu_write(cpuhp_state.state, CPUHP_ONLINE); which is obviously the right thing to do. Except because of the ordering issue, it actually failed miserably and unexpectedly on arm64. So this just fixes the ordering, and changes the name of the function to be 'boot_cpu_hotplug_init()' to make it obvious that it's about cpu hotplug state, because the core CPU state was supposed to have already been done earlier. Marked for stable, since the (not yet merged) patch that will show this problem is marked for stable. Reported-by: Vlastimil Babka Reported-by: Mian Yousaf Kaukab Suggested-by: Catalin Marinas Acked-by: Thomas Gleixner Cc: Will Deacon Cc: stable@kernel.org Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

init: fix false positives in W+X checking

2018-06-20T19:02:57+00:00

[ Upstream commit ae646f0b9ca135b87bc73ff606ef996c3029780a ] load_module() creates W+X mappings via __vmalloc_node_range() (from layout_and_allocate()->move_module()->module_alloc()) by using PAGE_KERNEL_EXEC. These mappings are later cleaned up via "call_rcu_sched(&freeinit->rcu, do_free_init)" from do_init_module(). This is a problem because call_rcu_sched() queues work, which can be run after debug_checkwx() is run, resulting in a race condition. If hit, the race results in a nasty splat about insecure W+X mappings, which results in a poor user experience as these are not the mappings that debug_checkwx() is intended to catch. This issue is observed on multiple arm64 platforms, and has been artificially triggered on an x86 platform. Address the race by flushing the queued work before running the arch-defined mark_rodata_ro() which then calls debug_checkwx(). Link: http://lkml.kernel.org/r/1525103946-29526-1-git-send-email-jhugo@codeaurora.org Fixes: e1a58320a38d ("x86/mm: Warn on W^X mappings") Signed-off-by: Jeffrey Hugo Reported-by: Timur Tabi Reported-by: Jan Glauber Acked-by: Kees Cook Acked-by: Ingo Molnar Acked-by: Will Deacon Acked-by: Laura Abbott Cc: Mark Rutland Cc: Ard Biesheuvel Cc: Catalin Marinas Cc: Stephen Smalley Cc: Thomas Gleixner Cc: Peter Zijlstra Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

kmemcheck: remove annotations

2018-02-22T14:42:23+00:00

commit 4950276672fce5c241857540f8561c440663673d upstream. Patch series "kmemcheck: kill kmemcheck", v2. As discussed at LSF/MM, kill kmemcheck. KASan is a replacement that is able to work without the limitation of kmemcheck (single CPU, slow). KASan is already upstream. We are also not aware of any users of kmemcheck (or users who don't consider KASan as a suitable replacement). The only objection was that since KASAN wasn't supported by all GCC versions provided by distros at that time we should hold off for 2 years, and try again. Now that 2 years have passed, and all distros provide gcc that supports KASAN, kill kmemcheck again for the very same reasons. This patch (of 4): Remove kmemcheck annotations, and calls to kmemcheck from the kernel. [alexander.levin@verizon.com: correctly remove kmemcheck call from dma_map_sg_attrs] Link: http://lkml.kernel.org/r/20171012192151.26531-1-alexander.levin@verizon.com Link: http://lkml.kernel.org/r/20171007030159.22241-2-alexander.levin@verizon.com Signed-off-by: Sasha Levin Cc: Alexander Potapenko Cc: Eric W. Biederman Cc: Michal Hocko Cc: Pekka Enberg Cc: Steven Rostedt Cc: Tim Hansen Cc: Vegard Nossum Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

x86/mm/pti: Add infrastructure for page table isolation

2018-01-02T19:30:56+00:00

commit aa8c6248f8c75acfd610fe15d8cae23cf70d9d09 upstream. Add the initial files for kernel page table isolation, with a minimal init function and the boot time detection for this misfeature. Signed-off-by: Thomas Gleixner Reviewed-by: Borislav Petkov Cc: Andy Lutomirski Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: David Laight Cc: Denys Vlasenko Cc: Eduardo Valentin Cc: Greg KH Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Will Deacon Cc: aliguori@amazon.com Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: keescook@google.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

init: Invoke init_espfix_bsp() from mm_init()

2017-12-29T16:53:45+00:00

commit 613e396bc0d4c7604fba23256644e78454c68cf6 upstream. init_espfix_bsp() needs to be invoked before the page table isolation initialization. Move it into mm_init() which is the place where pti_init() will be added. While at it get rid of the #ifdeffery and provide proper stub functions. Signed-off-by: Thomas Gleixner Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman

init/main.c: extract early boot entropy from the passed cmdline

2017-09-09T01:26:50+00:00

Feed the boot command-line as to the /dev/random entropy pool Existing Android bootloaders usually pass data which may not be known by an external attacker on the kernel command-line. It may also be the case on other embedded systems. Sample command-line from a Google Pixel running CopperheadOS.... console=ttyHSL0,115200,n8 androidboot.console=ttyHSL0 androidboot.hardware=sailfish user_debug=31 ehci-hcd.park=3 lpm_levels.sleep_disabled=1 cma=32M@0-0xffffffff buildvariant=user veritykeyid=id:dfcb9db0089e5b3b4090a592415c28e1cb4545ab androidboot.bootdevice=624000.ufshc androidboot.verifiedbootstate=yellow androidboot.veritymode=enforcing androidboot.keymaster=1 androidboot.serialno=FA6CE0305299 androidboot.baseband=msm mdss_mdp.panel=1:dsi:0:qcom,mdss_dsi_samsung_ea8064tg_1080p_cmd:1:none:cfg:single_dsi androidboot.slot_suffix=_b fpsimd.fpsimd_settings=0 app_setting.use_app_setting=0 kernelflag=0x00000000 debugflag=0x00000000 androidboot.hardware.revision=PVT radioflag=0x00000000 radioflagex1=0x00000000 radioflagex2=0x00000000 cpumask=0x00000000 androidboot.hardware.ddr=4096MB,Hynix,LPDDR4 androidboot.ddrinfo=00000006 androidboot.ddrsize=4GB androidboot.hardware.color=GRA00 androidboot.hardware.ufs=32GB,Samsung androidboot.msm.hw_ver_id=268824801 androidboot.qf.st=2 androidboot.cid=11111111 androidboot.mid=G-2PW4100 androidboot.bootloader=8996-012001-1704121145 androidboot.oem_unlock_support=1 androidboot.fp_src=1 androidboot.htc.hrdump=detected androidboot.ramdump.opt=mem@2g:2g,mem@4g:2g androidboot.bootreason=reboot androidboot.ramdump_enable=0 ro root=/dev/dm-0 dm="system none ro,0 1 android-verity /dev/sda34" rootwait skip_initramfs init=/init androidboot.wificountrycode=US androidboot.boottime=1BLL:85,1BLE:669,2BLL:0,2BLE:1777,SW:6,KL:8136 Among other things, it contains a value unique to the device (androidboot.serialno=FA6CE0305299), unique to the OS builds for the device variant (veritykeyid=id:dfcb9db0089e5b3b4090a592415c28e1cb4545ab) and timings from the bootloader stages in milliseconds (androidboot.boottime=1BLL:85,1BLE:669,2BLL:0,2BLE:1777,SW:6,KL:8136). [tytso@mit.edu: changelog tweak] [labbott@redhat.com: line-wrapped command line] Link: http://lkml.kernel.org/r/20170816231458.2299-3-labbott@redhat.com Signed-off-by: Daniel Micay Signed-off-by: Laura Abbott Acked-by: Kees Cook Cc: "Theodore Ts'o" Cc: Laura Abbott Cc: Nick Kralevich Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

init: move stack canary initialization after setup_arch

2017-09-09T01:26:50+00:00

Patch series "Command line randomness", v3. A series to add the kernel command line as a source of randomness. This patch (of 2): Stack canary intialization involves getting a random number. Getting this random number may involve accessing caches or other architectural specific features which are not available until after the architecture is setup. Move the stack canary initialization later to accommodate this. Link: http://lkml.kernel.org/r/20170816231458.2299-2-labbott@redhat.com Signed-off-by: Laura Abbott Signed-off-by: Laura Abbott Acked-by: Kees Cook Cc: "Theodore Ts'o" Cc: Daniel Micay Cc: Nick Kralevich Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Merge branch 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu

2017-09-07T04:33:12+00:00

Pull percpu updates from Tejun Heo: "A lot of changes for percpu this time around. percpu inherited the same area allocator from the original pre-virtual-address-mapped implementation. This was from the time when percpu allocator wasn't used all that much and the implementation was focused on simplicity, with the unfortunate computational complexity of O(number of areas allocated from the chunk) per alloc / free. With the increase in percpu usage, we're hitting cases where the lack of scalability is hurting. The most prominent one right now is bpf perpcu map creation / destruction which may allocate and free a lot of entries consecutively and it's likely that the problem will become more prominent in the future. To address the issue, Dennis replaced the area allocator with hinted bitmap allocator which is more consistent. While the new allocator does perform a bit worse in some cases, it outperforms the old allocator way more than an order of magnitude in other more common scenarios while staying mostly flat in CPU overhead and completely flat in memory consumption" * 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (27 commits) percpu: update header to contain bitmap allocator explanation. percpu: update pcpu_find_block_fit to use an iterator percpu: use metadata blocks to update the chunk contig hint percpu: update free path to take advantage of contig hints percpu: update alloc path to only scan if contig hints are broken percpu: keep track of the best offset for contig hints percpu: skip chunks if the alloc does not fit in the contig hint percpu: add first_bit to keep track of the first free in the bitmap percpu: introduce bitmap metadata blocks percpu: replace area map allocator with bitmap percpu: generalize bitmap (un)populated iterators percpu: increase minimum percpu allocation size and align first regions percpu: introduce nr_empty_pop_pages to help empty page accounting percpu: change the number of pages marked in the first_chunk pop bitmap percpu: combine percpu address checks percpu: modify base_addr to be region specific percpu: setup_first_chunk rename schunk/dchunk to chunk percpu: end chunk area maps page aligned for the populated bitmap percpu: unify allocation of schunk and dchunk percpu: setup_first_chunk remove dyn_size and consolidate logic ...