09 Aug, 2016
1 commit
-
Limit per userns sysctls to only be opened for write by a holder
of CAP_SYS_RESOURCE.Add all of the necessary boilerplate for having per user namespace
sysctls.Acked-by: Kees Cook
Signed-off-by: "Eric W. Biederman"
24 May, 2016
1 commit
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CONFIG_MIPS32_N32=y but CONFIG_BINFMT_ELF disabled results in the
following linker errors:arch/mips/built-in.o: In function `elf_core_dump':
binfmt_elfn32.c:(.text+0x23dbc): undefined reference to `elf_core_extra_phdrs'
binfmt_elfn32.c:(.text+0x246e4): undefined reference to `elf_core_extra_data_size'
binfmt_elfn32.c:(.text+0x248d0): undefined reference to `elf_core_write_extra_phdrs'
binfmt_elfn32.c:(.text+0x24ac4): undefined reference to `elf_core_write_extra_data'CONFIG_MIPS32_O32=y but CONFIG_BINFMT_ELF disabled results in the following
linker errors:arch/mips/built-in.o: In function `elf_core_dump':
binfmt_elfo32.c:(.text+0x28a04): undefined reference to `elf_core_extra_phdrs'
binfmt_elfo32.c:(.text+0x29330): undefined reference to `elf_core_extra_data_size'
binfmt_elfo32.c:(.text+0x2951c): undefined reference to `elf_core_write_extra_phdrs'
binfmt_elfo32.c:(.text+0x29710): undefined reference to `elf_core_write_extra_data'This is because binfmt_elfn32 and binfmt_elfo32 are using symbols from
elfcore but for these configurations elfcore will not be built.Fixed by making elfcore selectable by a separate config symbol which
unlike the current mechanism can also be used from other directories
than kernel/, then having each flavor of ELF that relies on elfcore.o,
select it in Kconfig, including CONFIG_MIPS32_N32 and CONFIG_MIPS32_O32
which fixes this issue.Link: http://lkml.kernel.org/r/20160520141705.GA1913@linux-mips.org
Signed-off-by: Ralf Baechle
Reviewed-by: James Hogan
Cc: "Maciej W. Rozycki"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
23 Mar, 2016
1 commit
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kcov provides code coverage collection for coverage-guided fuzzing
(randomized testing). Coverage-guided fuzzing is a testing technique
that uses coverage feedback to determine new interesting inputs to a
system. A notable user-space example is AFL
(http://lcamtuf.coredump.cx/afl/). However, this technique is not
widely used for kernel testing due to missing compiler and kernel
support.kcov does not aim to collect as much coverage as possible. It aims to
collect more or less stable coverage that is function of syscall inputs.
To achieve this goal it does not collect coverage in soft/hard
interrupts and instrumentation of some inherently non-deterministic or
non-interesting parts of kernel is disbled (e.g. scheduler, locking).Currently there is a single coverage collection mode (tracing), but the
API anticipates additional collection modes. Initially I also
implemented a second mode which exposes coverage in a fixed-size hash
table of counters (what Quentin used in his original patch). I've
dropped the second mode for simplicity.This patch adds the necessary support on kernel side. The complimentary
compiler support was added in gcc revision 231296.We've used this support to build syzkaller system call fuzzer, which has
found 90 kernel bugs in just 2 months:https://github.com/google/syzkaller/wiki/Found-Bugs
We've also found 30+ bugs in our internal systems with syzkaller.
Another (yet unexplored) direction where kcov coverage would greatly
help is more traditional "blob mutation". For example, mounting a
random blob as a filesystem, or receiving a random blob over wire.Why not gcov. Typical fuzzing loop looks as follows: (1) reset
coverage, (2) execute a bit of code, (3) collect coverage, repeat. A
typical coverage can be just a dozen of basic blocks (e.g. an invalid
input). In such context gcov becomes prohibitively expensive as
reset/collect coverage steps depend on total number of basic
blocks/edges in program (in case of kernel it is about 2M). Cost of
kcov depends only on number of executed basic blocks/edges. On top of
that, kernel requires per-thread coverage because there are always
background threads and unrelated processes that also produce coverage.
With inlined gcov instrumentation per-thread coverage is not possible.kcov exposes kernel PCs and control flow to user-space which is
insecure. But debugfs should not be mapped as user accessible.Based on a patch by Quentin Casasnovas.
[akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode']
[akpm@linux-foundation.org: unbreak allmodconfig]
[akpm@linux-foundation.org: follow x86 Makefile layout standards]
Signed-off-by: Dmitry Vyukov
Reviewed-by: Kees Cook
Cc: syzkaller
Cc: Vegard Nossum
Cc: Catalin Marinas
Cc: Tavis Ormandy
Cc: Will Deacon
Cc: Quentin Casasnovas
Cc: Kostya Serebryany
Cc: Eric Dumazet
Cc: Alexander Potapenko
Cc: Kees Cook
Cc: Bjorn Helgaas
Cc: Sasha Levin
Cc: David Drysdale
Cc: Ard Biesheuvel
Cc: Andrey Ryabinin
Cc: Kirill A. Shutemov
Cc: Jiri Slaby
Cc: Ingo Molnar
Cc: Thomas Gleixner
Cc: "H. Peter Anvin"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
31 Jan, 2016
1 commit
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The file cgroup-debug.c had been removed from commit fe6934354f8e
(cgroups: move the cgroup debug subsys into cgroup.c to access internal state).
Remain the CFLAGS_REMOVE_cgroup-debug.o = $(CC_FLAGS_FTRACE)
useless in kernel/Makefile.Signed-off-by: Li Bin
Acked-by: Zefan Li
Signed-off-by: Tejun Heo
12 Sep, 2015
1 commit
-
Here is an implementation of a new system call, sys_membarrier(), which
executes a memory barrier on all threads running on the system. It is
implemented by calling synchronize_sched(). It can be used to
distribute the cost of user-space memory barriers asymmetrically by
transforming pairs of memory barriers into pairs consisting of
sys_membarrier() and a compiler barrier. For synchronization primitives
that distinguish between read-side and write-side (e.g. userspace RCU
[1], rwlocks), the read-side can be accelerated significantly by moving
the bulk of the memory barrier overhead to the write-side.The existing applications of which I am aware that would be improved by
this system call are as follows:* Through Userspace RCU library (http://urcu.so)
- DNS server (Knot DNS) https://www.knot-dns.cz/
- Network sniffer (http://netsniff-ng.org/)
- Distributed object storage (https://sheepdog.github.io/sheepdog/)
- User-space tracing (http://lttng.org)
- Network storage system (https://www.gluster.org/)
- Virtual routers (https://events.linuxfoundation.org/sites/events/files/slides/DPDK_RCU_0MQ.pdf)
- Financial software (https://lkml.org/lkml/2015/3/23/189)Those projects use RCU in userspace to increase read-side speed and
scalability compared to locking. Especially in the case of RCU used by
libraries, sys_membarrier can speed up the read-side by moving the bulk of
the memory barrier cost to synchronize_rcu().* Direct users of sys_membarrier
- core dotnet garbage collector (https://github.com/dotnet/coreclr/issues/198)Microsoft core dotnet GC developers are planning to use the mprotect()
side-effect of issuing memory barriers through IPIs as a way to implement
Windows FlushProcessWriteBuffers() on Linux. They are referring to
sys_membarrier in their github thread, specifically stating that
sys_membarrier() is what they are looking for.To explain the benefit of this scheme, let's introduce two example threads:
Thread A (non-frequent, e.g. executing liburcu synchronize_rcu())
Thread B (frequent, e.g. executing liburcu
rcu_read_lock()/rcu_read_unlock())In a scheme where all smp_mb() in thread A are ordering memory accesses
with respect to smp_mb() present in Thread B, we can change each
smp_mb() within Thread A into calls to sys_membarrier() and each
smp_mb() within Thread B into compiler barriers "barrier()".Before the change, we had, for each smp_mb() pairs:
Thread A Thread B
previous mem accesses previous mem accesses
smp_mb() smp_mb()
following mem accesses following mem accessesAfter the change, these pairs become:
Thread A Thread B
prev mem accesses prev mem accesses
sys_membarrier() barrier()
follow mem accesses follow mem accessesAs we can see, there are two possible scenarios: either Thread B memory
accesses do not happen concurrently with Thread A accesses (1), or they
do (2).1) Non-concurrent Thread A vs Thread B accesses:
Thread A Thread B
prev mem accesses
sys_membarrier()
follow mem accesses
prev mem accesses
barrier()
follow mem accessesIn this case, thread B accesses will be weakly ordered. This is OK,
because at that point, thread A is not particularly interested in
ordering them with respect to its own accesses.2) Concurrent Thread A vs Thread B accesses
Thread A Thread B
prev mem accesses prev mem accesses
sys_membarrier() barrier()
follow mem accesses follow mem accessesIn this case, thread B accesses, which are ensured to be in program
order thanks to the compiler barrier, will be "upgraded" to full
smp_mb() by synchronize_sched().* Benchmarks
On Intel Xeon E5405 (8 cores)
(one thread is calling sys_membarrier, the other 7 threads are busy
looping)1000 non-expedited sys_membarrier calls in 33s =3D 33 milliseconds/call.
* User-space user of this system call: Userspace RCU library
Both the signal-based and the sys_membarrier userspace RCU schemes
permit us to remove the memory barrier from the userspace RCU
rcu_read_lock() and rcu_read_unlock() primitives, thus significantly
accelerating them. These memory barriers are replaced by compiler
barriers on the read-side, and all matching memory barriers on the
write-side are turned into an invocation of a memory barrier on all
active threads in the process. By letting the kernel perform this
synchronization rather than dumbly sending a signal to every process
threads (as we currently do), we diminish the number of unnecessary wake
ups and only issue the memory barriers on active threads. Non-running
threads do not need to execute such barrier anyway, because these are
implied by the scheduler context switches.Results in liburcu:
Operations in 10s, 6 readers, 2 writers:
memory barriers in reader: 1701557485 reads, 2202847 writes
signal-based scheme: 9830061167 reads, 6700 writes
sys_membarrier: 9952759104 reads, 425 writes
sys_membarrier (dyn. check): 7970328887 reads, 425 writesThe dynamic sys_membarrier availability check adds some overhead to
the read-side compared to the signal-based scheme, but besides that,
sys_membarrier slightly outperforms the signal-based scheme. However,
this non-expedited sys_membarrier implementation has a much slower grace
period than signal and memory barrier schemes.Besides diminishing the number of wake-ups, one major advantage of the
membarrier system call over the signal-based scheme is that it does not
need to reserve a signal. This plays much more nicely with libraries,
and with processes injected into for tracing purposes, for which we
cannot expect that signals will be unused by the application.An expedited version of this system call can be added later on to speed
up the grace period. Its implementation will likely depend on reading
the cpu_curr()->mm without holding each CPU's rq lock.This patch adds the system call to x86 and to asm-generic.
[1] http://urcu.so
membarrier(2) man page:
MEMBARRIER(2) Linux Programmer's Manual MEMBARRIER(2)
NAME
membarrier - issue memory barriers on a set of threadsSYNOPSIS
#includeint membarrier(int cmd, int flags);
DESCRIPTION
The cmd argument is one of the following:MEMBARRIER_CMD_QUERY
Query the set of supported commands. It returns a bitmask of
supported commands.MEMBARRIER_CMD_SHARED
Execute a memory barrier on all threads running on the system.
Upon return from system call, the caller thread is ensured that
all running threads have passed through a state where all memory
accesses to user-space addresses match program order between
entry to and return from the system call (non-running threads
are de facto in such a state). This covers threads from all pro=E2=80=90
cesses running on the system. This command returns 0.The flags argument needs to be 0. For future extensions.
All memory accesses performed in program order from each targeted
thread is guaranteed to be ordered with respect to sys_membarrier(). If
we use the semantic "barrier()" to represent a compiler barrier forcing
memory accesses to be performed in program order across the barrier,
and smp_mb() to represent explicit memory barriers forcing full memory
ordering across the barrier, we have the following ordering table for
each pair of barrier(), sys_membarrier() and smp_mb():The pair ordering is detailed as (O: ordered, X: not ordered):
barrier() smp_mb() sys_membarrier()
barrier() X X O
smp_mb() X O O
sys_membarrier() O O ORETURN VALUE
On success, these system calls return zero. On error, -1 is returned,
and errno is set appropriately. For a given command, with flags
argument set to 0, this system call is guaranteed to always return the
same value until reboot.ERRORS
ENOSYS System call is not implemented.EINVAL Invalid arguments.
Linux 2015-04-15 MEMBARRIER(2)
Signed-off-by: Mathieu Desnoyers
Reviewed-by: Paul E. McKenney
Reviewed-by: Josh Triplett
Cc: KOSAKI Motohiro
Cc: Steven Rostedt
Cc: Nicholas Miell
Cc: Ingo Molnar
Cc: Alan Cox
Cc: Lai Jiangshan
Cc: Stephen Hemminger
Cc: Thomas Gleixner
Cc: Peter Zijlstra
Cc: David Howells
Cc: Pranith Kumar
Cc: Michael Kerrisk
Cc: Shuah Khan
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
11 Sep, 2015
2 commits
-
There are two kexec load syscalls, kexec_load another and kexec_file_load.
kexec_file_load has been splited as kernel/kexec_file.c. In this patch I
split kexec_load syscall code to kernel/kexec.c.And add a new kconfig option KEXEC_CORE, so we can disable kexec_load and
use kexec_file_load only, or vice verse.The original requirement is from Ted Ts'o, he want kexec kernel signature
being checked with CONFIG_KEXEC_VERIFY_SIG enabled. But kexec-tools use
kexec_load syscall can bypass the checking.Vivek Goyal proposed to create a common kconfig option so user can compile
in only one syscall for loading kexec kernel. KEXEC/KEXEC_FILE selects
KEXEC_CORE so that old config files still work.Because there's general code need CONFIG_KEXEC_CORE, so I updated all the
architecture Kconfig with a new option KEXEC_CORE, and let KEXEC selects
KEXEC_CORE in arch Kconfig. Also updated general kernel code with to
kexec_load syscall.[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Dave Young
Cc: Eric W. Biederman
Cc: Vivek Goyal
Cc: Petr Tesarik
Cc: Theodore Ts'o
Cc: Josh Boyer
Cc: David Howells
Cc: Geert Uytterhoeven
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Split kexec_file syscall related code to another file kernel/kexec_file.c
so that the #ifdef CONFIG_KEXEC_FILE in kexec.c can be dropped.Sharing variables and functions are moved to kernel/kexec_internal.h per
suggestion from Vivek and Petr.[akpm@linux-foundation.org: fix bisectability]
[akpm@linux-foundation.org: declare the various arch_kexec functions]
[akpm@linux-foundation.org: fix build]
Signed-off-by: Dave Young
Cc: Eric W. Biederman
Cc: Vivek Goyal
Cc: Petr Tesarik
Cc: Theodore Ts'o
Cc: Josh Boyer
Cc: David Howells
Cc: Geert Uytterhoeven
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
09 Sep, 2015
3 commits
-
Pull libnvdimm updates from Dan Williams:
"This update has successfully completed a 0day-kbuild run and has
appeared in a linux-next release. The changes outside of the typical
drivers/nvdimm/ and drivers/acpi/nfit.[ch] paths are related to the
removal of IORESOURCE_CACHEABLE, the introduction of memremap(), and
the introduction of ZONE_DEVICE + devm_memremap_pages().Summary:
- Introduce ZONE_DEVICE and devm_memremap_pages() as a generic
mechanism for adding device-driver-discovered memory regions to the
kernel's direct map.This facility is used by the pmem driver to enable pfn_to_page()
operations on the page frames returned by DAX ('direct_access' in
'struct block_device_operations').For now, the 'memmap' allocation for these "device" pages comes
from "System RAM". Support for allocating the memmap from device
memory will arrive in a later kernel.- Introduce memremap() to replace usages of ioremap_cache() and
ioremap_wt(). memremap() drops the __iomem annotation for these
mappings to memory that do not have i/o side effects. The
replacement of ioremap_cache() with memremap() is limited to the
pmem driver to ease merging the api change in v4.3.Completion of the conversion is targeted for v4.4.
- Similar to the usage of memcpy_to_pmem() + wmb_pmem() in the pmem
driver, update the VFS DAX implementation and PMEM api to provide
persistence guarantees for kernel operations on a DAX mapping.- Convert the ACPI NFIT 'BLK' driver to map the block apertures as
cacheable to improve performance.- Miscellaneous updates and fixes to libnvdimm including support for
issuing "address range scrub" commands, clarifying the optimal
'sector size' of pmem devices, a clarification of the usage of the
ACPI '_STA' (status) property for DIMM devices, and other minor
fixes"* tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (34 commits)
libnvdimm, pmem: direct map legacy pmem by default
libnvdimm, pmem: 'struct page' for pmem
libnvdimm, pfn: 'struct page' provider infrastructure
x86, pmem: clarify that ARCH_HAS_PMEM_API implies PMEM mapped WB
add devm_memremap_pages
mm: ZONE_DEVICE for "device memory"
mm: move __phys_to_pfn and __pfn_to_phys to asm/generic/memory_model.h
dax: drop size parameter to ->direct_access()
nd_blk: change aperture mapping from WC to WB
nvdimm: change to use generic kvfree()
pmem, dax: have direct_access use __pmem annotation
dax: update I/O path to do proper PMEM flushing
pmem: add copy_from_iter_pmem() and clear_pmem()
pmem, x86: clean up conditional pmem includes
pmem: remove layer when calling arch_has_wmb_pmem()
pmem, x86: move x86 PMEM API to new pmem.h header
libnvdimm, e820: make CONFIG_X86_PMEM_LEGACY a tristate option
pmem: switch to devm_ allocations
devres: add devm_memremap
libnvdimm, btt: write and validate parent_uuid
... -
Pull audit update from Paul Moore:
"This is one of the larger audit patchsets in recent history,
consisting of eight patches and almost 400 lines of changes.The bulk of the patchset is the new "audit by executable"
functionality which allows admins to set an audit watch based on the
executable on disk. Prior to this, admins could only track an
application by PID, which has some obvious limitations.Beyond the new functionality we also have some refcnt fixes and a few
minor cleanups"* 'upstream' of git://git.infradead.org/users/pcmoore/audit:
fixup: audit: implement audit by executable
audit: implement audit by executable
audit: clean simple fsnotify implementation
audit: use macros for unset inode and device values
audit: make audit_del_rule() more robust
audit: fix uninitialized variable in audit_add_rule()
audit: eliminate unnecessary extra layer of watch parent references
audit: eliminate unnecessary extra layer of watch references -
Pull security subsystem updates from James Morris:
"Highlights:- PKCS#7 support added to support signed kexec, also utilized for
module signing. See comments in 3f1e1bea.** NOTE: this requires linking against the OpenSSL library, which
must be installed, e.g. the openssl-devel on Fedora **- Smack
- add IPv6 host labeling; ignore labels on kernel threads
- support smack labeling mounts which use binary mount data- SELinux:
- add ioctl whitelisting (see
http://kernsec.org/files/lss2015/vanderstoep.pdf)
- fix mprotect PROT_EXEC regression caused by mm change- Seccomp:
- add ptrace options for suspend/resume"* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (57 commits)
PKCS#7: Add OIDs for sha224, sha284 and sha512 hash algos and use them
Documentation/Changes: Now need OpenSSL devel packages for module signing
scripts: add extract-cert and sign-file to .gitignore
modsign: Handle signing key in source tree
modsign: Use if_changed rule for extracting cert from module signing key
Move certificate handling to its own directory
sign-file: Fix warning about BIO_reset() return value
PKCS#7: Add MODULE_LICENSE() to test module
Smack - Fix build error with bringup unconfigured
sign-file: Document dependency on OpenSSL devel libraries
PKCS#7: Appropriately restrict authenticated attributes and content type
KEYS: Add a name for PKEY_ID_PKCS7
PKCS#7: Improve and export the X.509 ASN.1 time object decoder
modsign: Use extract-cert to process CONFIG_SYSTEM_TRUSTED_KEYS
extract-cert: Cope with multiple X.509 certificates in a single file
sign-file: Generate CMS message as signature instead of PKCS#7
PKCS#7: Support CMS messages also [RFC5652]
X.509: Change recorded SKID & AKID to not include Subject or Issuer
PKCS#7: Check content type and versions
MAINTAINERS: The keyrings mailing list has moved
...
15 Aug, 2015
1 commit
-
Existing users of ioremap_cache() are mapping memory that is known in
advance to not have i/o side effects. These users are forced to cast
away the __iomem annotation, or otherwise neglect to fix the sparse
errors thrown when dereferencing pointers to this memory. Provide
memremap() as a non __iomem annotated ioremap_*() in the case when
ioremap is otherwise a pointer to cacheable memory. Empirically,
ioremap_() call sites are seeking memory-like semantics
(e.g. speculative reads, and prefetching permitted).memremap() is a break from the ioremap implementation pattern of adding
a new memremap_() for each mapping type and having silent
compatibility fall backs. Instead, the implementation defines flags
that are passed to the central memremap() and if a mapping type is not
supported by an arch memremap returns NULL.We introduce a memremap prototype as a trivial wrapper of
ioremap_cache() and ioremap_wt(). Later, once all ioremap_cache() and
ioremap_wt() usage has been removed from drivers we teach archs to
implement arch_memremap() with the ability to strictly enforce the
mapping type.Cc: Arnd Bergmann
Reviewed-by: Christoph Hellwig
Signed-off-by: Dan Williams
14 Aug, 2015
1 commit
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Move certificate handling out of the kernel/ directory and into a certs/
directory to get all the weird stuff in one place and move the generated
signing keys into this directory.Signed-off-by: David Howells
Reviewed-by: David Woodhouse
13 Aug, 2015
1 commit
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Fix up the dependencies somewhat too, while we're at it.
Signed-off-by: David Woodhouse
Signed-off-by: David Howells
07 Aug, 2015
5 commits
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Let the user explicitly provide a file containing trusted keys, instead of
just automatically finding files matching *.x509 in the build tree and
trusting whatever we find. This really ought to be an *explicit*
configuration, and the build rules for dealing with the files were
fairly painful too.Fix applied from James Morris that removes an '=' from a macro definition
in kernel/Makefile as this is a feature that only exists from GNU make 3.82
onwards.Signed-off-by: David Woodhouse
Signed-off-by: David Howells -
The current rule for generating signing_key.priv and signing_key.x509 is
a classic example of a bad rule which has a tendency to break parallel
make. When invoked to create *either* target, it generates the other
target as a side-effect that make didn't predict.So let's switch to using a single file signing_key.pem which contains
both key and certificate. That matches what we do in the case of an
external key specified by CONFIG_MODULE_SIG_KEY anyway, so it's also
slightly cleaner.Signed-off-by: David Woodhouse
Signed-off-by: David Howells -
Where an external PEM file or PKCS#11 URI is given, we can get the cert
from it for ourselves instead of making the user drop signing_key.x509
in place for us.Signed-off-by: David Woodhouse
Signed-off-by: David Howells -
Signed-off-by: David Woodhouse
Signed-off-by: David Howells -
This is to be used to audit by executable path rules, but audit watches should
be able to share this code eventually.At the moment the audit watch code is a lot more complex. That code only
creates one fsnotify watch per parent directory. That 'audit_parent' in
turn has a list of 'audit_watches' which contain the name, ino, dev of
the specific object we care about. This just creates one fsnotify watch
per object we care about. So if you watch 100 inodes in /etc this code
will create 100 fsnotify watches on /etc. The audit_watch code will
instead create 1 fsnotify watch on /etc (the audit_parent) and then 100
individual watches chained from that fsnotify mark.We should be able to convert the audit_watch code to do one fsnotify
mark per watch and simplify things/remove a whole lot of code. After
that conversion we should be able to convert the audit_fsnotify code to
support that hierarchy if the optimization is necessary.Move the access to the entry for audit_match_signal() to the beginning of
the audit_del_rule() function in case the entry found is the same one passed
in. This will enable it to be used by audit_autoremove_mark_rule(),
kill_rules() and audit_remove_parent_watches().This is a heavily modified and merged version of two patches originally
submitted by Eric Paris.Cc: Peter Moody
Cc: Eric Paris
Signed-off-by: Richard Guy Briggs
[PM: added a space after a declaration to keep ./scripts/checkpatch happy]
Signed-off-by: Paul Moore
15 Jul, 2015
1 commit
-
Adds a new single-purpose PIDs subsystem to limit the number of
tasks that can be forked inside a cgroup. Essentially this is an
implementation of RLIMIT_NPROC that applies to a cgroup rather than a
process tree.However, it should be noted that organisational operations (adding and
removing tasks from a PIDs hierarchy) will *not* be prevented. Rather,
the number of tasks in the hierarchy cannot exceed the limit through
forking. This is due to the fact that, in the unified hierarchy, attach
cannot fail (and it is not possible for a task to overcome its PIDs
cgroup policy limit by attaching to a child cgroup -- even if migrating
mid-fork it must be able to fork in the parent first).PIDs are fundamentally a global resource, and it is possible to reach
PID exhaustion inside a cgroup without hitting any reasonable kmemcg
policy. Once you've hit PID exhaustion, you're only in a marginally
better state than OOM. This subsystem allows PID exhaustion inside a
cgroup to be prevented.Signed-off-by: Aleksa Sarai
Signed-off-by: Tejun Heo
03 Jul, 2015
1 commit
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It's a bug in our Makefile rules, make it show what the changing
certificate list was, and make it a warning so that people actually see
it.Signed-off-by: Linus Torvalds
01 May, 2015
1 commit
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Change default key details to be more obviously unspecified.
Reported-by: Linus Torvalds
Signed-off-by: David Howells
Acked-by: James Morris
Signed-off-by: Linus Torvalds
16 Apr, 2015
1 commit
-
There are a lot of embedded systems that run most or all of their
functionality in init, running as root:root. For these systems,
supporting multiple users is not necessary.This patch adds a new symbol, CONFIG_MULTIUSER, that makes support for
non-root users, non-root groups, and capabilities optional. It is enabled
under CONFIG_EXPERT menu.When this symbol is not defined, UID and GID are zero in any possible case
and processes always have all capabilities.The following syscalls are compiled out: setuid, setregid, setgid,
setreuid, setresuid, getresuid, setresgid, getresgid, setgroups,
getgroups, setfsuid, setfsgid, capget, capset.Also, groups.c is compiled out completely.
In kernel/capability.c, capable function was moved in order to avoid
adding two ifdef blocks.This change saves about 25 KB on a defconfig build. The most minimal
kernels have total text sizes in the high hundreds of kB rather than
low MB. (The 25k goes down a bit with allnoconfig, but not that much.The kernel was booted in Qemu. All the common functionalities work.
Adding users/groups is not possible, failing with -ENOSYS.Bloat-o-meter output:
add/remove: 7/87 grow/shrink: 19/397 up/down: 1675/-26325 (-24650)[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Iulia Manda
Reviewed-by: Josh Triplett
Acked-by: Geert Uytterhoeven
Tested-by: Paul E. McKenney
Reviewed-by: Paul E. McKenney
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
12 Feb, 2015
2 commits
-
Pull security layer updates from James Morris:
"Highlights:- Smack adds secmark support for Netfilter
- /proc/keys is now mandatory if CONFIG_KEYS=y
- TPM gets its own device class
- Added TPM 2.0 support
- Smack file hook rework (all Smack users should review this!)"* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (64 commits)
cipso: don't use IPCB() to locate the CIPSO IP option
SELinux: fix error code in policydb_init()
selinux: add security in-core xattr support for pstore and debugfs
selinux: quiet the filesystem labeling behavior message
selinux: Remove unused function avc_sidcmp()
ima: /proc/keys is now mandatory
Smack: Repair netfilter dependency
X.509: silence asn1 compiler debug output
X.509: shut up about included cert for silent build
KEYS: Make /proc/keys unconditional if CONFIG_KEYS=y
MAINTAINERS: email update
tpm/tpm_tis: Add missing ifdef CONFIG_ACPI for pnp_acpi_device
smack: fix possible use after frees in task_security() callers
smack: Add missing logging in bidirectional UDS connect check
Smack: secmark support for netfilter
Smack: Rework file hooks
tpm: fix format string error in tpm-chip.c
char/tpm/tpm_crb: fix build error
smack: Fix a bidirectional UDS connect check typo
smack: introduce a special case for tmpfs in smack_d_instantiate()
... -
Pull s390 updates from Martin Schwidefsky:
- The remaining patches for the z13 machine support: kernel build
option for z13, the cache synonym avoidance, SMT support,
compare-and-delay for spinloops and the CES5S crypto adapater.- The ftrace support for function tracing with the gcc hotpatch option.
This touches common code Makefiles, Steven is ok with the changes.- The hypfs file system gets an extension to access diagnose 0x0c data
in user space for performance analysis for Linux running under z/VM.- The iucv hvc console gets wildcard spport for the user id filtering.
- The cacheinfo code is converted to use the generic infrastructure.
- Cleanup and bug fixes.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (42 commits)
s390/process: free vx save area when releasing tasks
s390/hypfs: Eliminate hypfs interval
s390/hypfs: Add diagnose 0c support
s390/cacheinfo: don't use smp_processor_id() in preemptible context
s390/zcrypt: fixed domain scanning problem (again)
s390/smp: increase maximum value of NR_CPUS to 512
s390/jump label: use different nop instruction
s390/jump label: add sanity checks
s390/mm: correct missing space when reporting user process faults
s390/dasd: cleanup profiling
s390/dasd: add locking for global_profile access
s390/ftrace: hotpatch support for function tracing
ftrace: let notrace function attribute disable hotpatching if necessary
ftrace: allow architectures to specify ftrace compile options
s390: reintroduce diag 44 calls for cpu_relax()
s390/zcrypt: Add support for new crypto express (CEX5S) adapter.
s390/zcrypt: Number of supported ap domains is not retrievable.
s390/spinlock: add compare-and-delay to lock wait loops
s390/tape: remove redundant if statement
s390/hvc_iucv: add simple wildcard matches to the iucv allow filter
...
29 Jan, 2015
1 commit
-
If the kernel is compiled with function tracer support the -pg compile option
is passed to gcc to generate extra code into the prologue of each function.This patch replaces the "open-coded" -pg compile flag with a CC_FLAGS_FTRACE
makefile variable which architectures can override if a different option
should be used for code generation.Acked-by: Steven Rostedt
Signed-off-by: Heiko Carstens
Signed-off-by: Martin Schwidefsky
23 Jan, 2015
1 commit
-
Every kernel build that includes X.509 support prints out
a message like- Including cert signing_key.x509
This may be useful for some cases, but when doing automated
build tests, it just means noise.To hide the message, this uses '$(kecho)' for printing the
message, which means we still see it when building with V=1,
but not at the normal level or when building with 'make -s'.Signed-off-by: Arnd Bergmann
Signed-off-by: David Howells
22 Dec, 2014
1 commit
-
This commit introduces code for the live patching core. It implements
an ftrace-based mechanism and kernel interface for doing live patching
of kernel and kernel module functions.It represents the greatest common functionality set between kpatch and
kgraft and can accept patches built using either method.This first version does not implement any consistency mechanism that
ensures that old and new code do not run together. In practice, ~90% of
CVEs are safe to apply in this way, since they simply add a conditional
check. However, any function change that can not execute safely with
the old version of the function can _not_ be safely applied in this
version.[ jkosina@suse.cz: due to the number of contributions that got folded into
this original patch from Seth Jennings, add SUSE's copyright as well, as
discussed via e-mail ]Signed-off-by: Seth Jennings
Signed-off-by: Josh Poimboeuf
Reviewed-by: Miroslav Benes
Reviewed-by: Petr Mladek
Reviewed-by: Masami Hiramatsu
Signed-off-by: Miroslav Benes
Signed-off-by: Petr Mladek
Signed-off-by: Jiri Kosina
11 Dec, 2014
1 commit
-
All memory accounting and limiting has been switched over to the
lockless page counters. Bye, res_counter![akpm@linux-foundation.org: update Documentation/cgroups/memory.txt]
[mhocko@suse.cz: ditch the last remainings of res_counter]
Signed-off-by: Johannes Weiner
Acked-by: Vladimir Davydov
Acked-by: Michal Hocko
Cc: Tejun Heo
Cc: David Rientjes
Cc: Paul Bolle
Signed-off-by: Michal Hocko
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
28 Oct, 2014
1 commit
-
introduce two configs:
- hidden CONFIG_BPF to select eBPF interpreter that classic socket filters
depend on
- visible CONFIG_BPF_SYSCALL (default off) that tracing and sockets can usethat solves several problems:
- tracing and others that wish to use eBPF don't need to depend on NET.
They can use BPF_SYSCALL to allow loading from userspace or select BPF
to use it directly from kernel in NET-less configs.
- in 3.18 programs cannot be attached to events yet, so don't force it on
- when the rest of eBPF infra is there in 3.19+, it's still useful to
switch it off to minimize kernel sizebloat-o-meter on x64 shows:
add/remove: 0/60 grow/shrink: 0/2 up/down: 0/-15601 (-15601)tested with many different config combinations. Hopefully didn't miss anything.
Signed-off-by: Alexei Starovoitov
Acked-by: Daniel Borkmann
Signed-off-by: David S. Miller
09 Aug, 2014
1 commit
-
This patch series does not do kernel signature verification yet. I plan
to post another patch series for that. Now distributions are already
signing PE/COFF bzImage with PKCS7 signature I plan to parse and verify
those signatures.Primary goal of this patchset is to prepare groundwork so that kernel
image can be signed and signatures be verified during kexec load. This
should help with two things.- It should allow kexec/kdump on secureboot enabled machines.
- In general it can help even without secureboot. By being able to verify
kernel image signature in kexec, it should help with avoiding module
signing restrictions. Matthew Garret showed how to boot into a custom
kernel, modify first kernel's memory and then jump back to old kernel and
bypass any policy one wants to.This patch (of 15):
Kexec wants to use bin2c and it wants to use it really early in the build
process. See arch/x86/purgatory/ code in later patches.So move bin2c in scripts/basic so that it can be built very early and
be usable by arch/x86/purgatory/Signed-off-by: Vivek Goyal
Cc: Borislav Petkov
Cc: Michael Kerrisk
Cc: Yinghai Lu
Cc: Eric Biederman
Cc: H. Peter Anvin
Cc: Matthew Garrett
Cc: Greg Kroah-Hartman
Cc: Dave Young
Cc: WANG Chao
Cc: Baoquan He
Cc: Andy Lutomirski
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Aug, 2014
1 commit
-
Pull networking updates from David Miller:
"Highlights:1) Steady transitioning of the BPF instructure to a generic spot so
all kernel subsystems can make use of it, from Alexei Starovoitov.2) SFC driver supports busy polling, from Alexandre Rames.
3) Take advantage of hash table in UDP multicast delivery, from David
Held.4) Lighten locking, in particular by getting rid of the LRU lists, in
inet frag handling. From Florian Westphal.5) Add support for various RFC6458 control messages in SCTP, from
Geir Ola Vaagland.6) Allow to filter bridge forwarding database dumps by device, from
Jamal Hadi Salim.7) virtio-net also now supports busy polling, from Jason Wang.
8) Some low level optimization tweaks in pktgen from Jesper Dangaard
Brouer.9) Add support for ipv6 address generation modes, so that userland
can have some input into the process. From Jiri Pirko.10) Consolidate common TCP connection request code in ipv4 and ipv6,
from Octavian Purdila.11) New ARP packet logger in netfilter, from Pablo Neira Ayuso.
12) Generic resizable RCU hash table, with intial users in netlink and
nftables. From Thomas Graf.13) Maintain a name assignment type so that userspace can see where a
network device name came from (enumerated by kernel, assigned
explicitly by userspace, etc.) From Tom Gundersen.14) Automatic flow label generation on transmit in ipv6, from Tom
Herbert.15) New packet timestamping facilities from Willem de Bruijn, meant to
assist in measuring latencies going into/out-of the packet
scheduler, latency from TCP data transmission to ACK, etc"* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1536 commits)
cxgb4 : Disable recursive mailbox commands when enabling vi
net: reduce USB network driver config options.
tg3: Modify tg3_tso_bug() to handle multiple TX rings
amd-xgbe: Perform phy connect/disconnect at dev open/stop
amd-xgbe: Use dma_set_mask_and_coherent to set DMA mask
net: sun4i-emac: fix memory leak on bad packet
sctp: fix possible seqlock seadlock in sctp_packet_transmit()
Revert "net: phy: Set the driver when registering an MDIO bus device"
cxgb4vf: Turn off SGE RX/TX Callback Timers and interrupts in PCI shutdown routine
team: Simplify return path of team_newlink
bridge: Update outdated comment on promiscuous mode
net-timestamp: ACK timestamp for bytestreams
net-timestamp: TCP timestamping
net-timestamp: SCHED timestamp on entering packet scheduler
net-timestamp: add key to disambiguate concurrent datagrams
net-timestamp: move timestamp flags out of sk_flags
net-timestamp: extend SCM_TIMESTAMPING ancillary data struct
cxgb4i : Move stray CPL definitions to cxgb4 driver
tcp: reduce spurious retransmits due to transient SACK reneging
qlcnic: Initialize dcbnl_ops before register_netdev
...
24 Jul, 2014
1 commit
-
BPF is used in several kernel components. This split creates logical boundary
between generic eBPF core and the restkernel/bpf/core.c: eBPF interpreter
net/core/filter.c: classic->eBPF converter, classic verifiers, socket filters
This patch only moves functions.
Signed-off-by: Alexei Starovoitov
Signed-off-by: David S. Miller
23 Jun, 2014
1 commit
-
Except for Kconfig.HZ. That needs a separate treatment.
Signed-off-by: Thomas Gleixner
01 Apr, 2014
2 commits
-
Pull x86 LTO changes from Peter Anvin:
"More infrastructure work in preparation for link-time optimization
(LTO). Most of these changes is to make sure symbols accessed from
assembly code are properly marked as visible so the linker doesn't
remove them.My understanding is that the changes to support LTO are still not
upstream in binutils, but are on the way there. This patchset should
conclude the x86-specific changes, and remaining patches to actually
enable LTO will be fed through the Kbuild tree (other than keeping up
with changes to the x86 code base, of course), although not
necessarily in this merge window"* 'x86-asmlinkage-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
Kbuild, lto: Handle basic LTO in modpost
Kbuild, lto: Disable LTO for asm-offsets.c
Kbuild, lto: Add a gcc-ld script to let run gcc as ld
Kbuild, lto: add ld-version and ld-ifversion macros
Kbuild, lto: Drop .number postfixes in modpost
Kbuild, lto, workaround: Don't warn for initcall_reference in modpost
lto: Disable LTO for sys_ni
lto: Handle LTO common symbols in module loader
lto, workaround: Add workaround for initcall reordering
lto: Make asmlinkage __visible
x86, lto: Disable LTO for the x86 VDSO
initconst, x86: Fix initconst mistake in ts5500 code
initconst: Fix initconst mistake in dcdbas
asmlinkage: Make trace_hardirqs_on/off_caller visible
asmlinkage, x86: Fix 32bit memcpy for LTO
asmlinkage Make __stack_chk_failed and memcmp visible
asmlinkage: Mark rwsem functions that can be called from assembler asmlinkage
asmlinkage: Make main_extable_sort_needed visible
asmlinkage, mutex: Mark __visible
asmlinkage: Make trace_hardirq visible
... -
Pull scheduler changes from Ingo Molnar:
"Bigger changes:- sched/idle restructuring: they are WIP preparation for deeper
integration between the scheduler and idle state selection, by
Nicolas Pitre.- add NUMA scheduling pseudo-interleaving, by Rik van Riel.
- optimize cgroup context switches, by Peter Zijlstra.
- RT scheduling enhancements, by Thomas Gleixner.
The rest is smaller changes, non-urgnt fixes and cleanups"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (68 commits)
sched: Clean up the task_hot() function
sched: Remove double calculation in fix_small_imbalance()
sched: Fix broken setscheduler()
sparc64, sched: Remove unused sparc64_multi_core
sched: Remove unused mc_capable() and smt_capable()
sched/numa: Move task_numa_free() to __put_task_struct()
sched/fair: Fix endless loop in idle_balance()
sched/core: Fix endless loop in pick_next_task()
sched/fair: Push down check for high priority class task into idle_balance()
sched/rt: Fix picking RT and DL tasks from empty queue
trace: Replace hardcoding of 19 with MAX_NICE
sched: Guarantee task priority in pick_next_task()
sched/idle: Remove stale old file
sched: Put rq's sched_avg under CONFIG_FAIR_GROUP_SCHED
cpuidle/arm64: Remove redundant cpuidle_idle_call()
cpuidle/powernv: Remove redundant cpuidle_idle_call()
sched, nohz: Exclude isolated cores from load balancing
sched: Fix select_task_rq_fair() description comments
workqueue: Replace hardcoding of -20 and 19 with MIN_NICE and MAX_NICE
sys: Replace hardcoding of -20 and 19 with MIN_NICE and MAX_NICE
...
24 Feb, 2014
1 commit
-
Because rcu_torture_random() will be used by the locking equivalent to
rcutorture, pull it out into its own module. This new module cannot
be separately configured, instead, use the Kconfig "select" statement
from the Kconfig options of tests depending on it.Suggested-by: Rusty Russell
Signed-off-by: Paul E. McKenney
14 Feb, 2014
1 commit
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The assembler alias code in cond_syscall does not work
when compiled for LTO. Just disable LTO for that file.Signed-off-by: Andi Kleen
Link: http://lkml.kernel.org/r/1391846481-31491-6-git-send-email-ak@linux.intel.com
Signed-off-by: H. Peter Anvin
11 Feb, 2014
1 commit
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Integration of cpuidle with the scheduler requires that the idle loop be
closely integrated with the scheduler proper. Moving cpu/idle.c into the
sched directory will allow for a smoother integration, and eliminate a
subdirectory which contained only one source file.Signed-off-by: Nicolas Pitre
Signed-off-by: Peter Zijlstra
Cc: Linus Torvalds
Cc: Andrew Morton
Cc: Thomas Gleixner
Link: http://lkml.kernel.org/r/alpine.LFD.2.11.1401301102210.1652@knanqh.ubzr
Signed-off-by: Ingo Molnar
13 Dec, 2013
2 commits
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Always remove generated SYSTEM_TRUSTED_KEYRING files while doing make mrproper.
Signed-off-by: Kirill Tkhai
Signed-off-by: David Howells -
Fix the gathering of certificates from both the source tree and the build tree
to correctly calculate the pathnames of all the certificates.The problem was that if the default generated cert, signing_key.x509, didn't
exist then it would not have a path attached and if it did, it would have a
path attached.This means that the contents of kernel/.x509.list would change between the
first compilation in a directory and the second. After the second it would
remain stable because the signing_key.x509 file exists.The consequence was that the kernel would get relinked unconditionally on the
second recompilation. The second recompilation would also show something like
this:X.509 certificate list changed
CERTS kernel/x509_certificate_list
- Including cert /home/torvalds/v2.6/linux/signing_key.x509
AS kernel/system_certificates.o
LD kernel/built-in.owhich is why the relink would happen.
Unfortunately, it isn't a simple matter of just sticking a path on the front
of the filename of the certificate in the build directory as make can't then
work out how to build it.So the path has to be prepended to the name for sorting and duplicate
elimination and then removed for the make rule if it is in the build tree.Reported-by: Linus Torvalds
Signed-off-by: David Howells
