This changes 'do_execve()' to get the executable name as a 'struct
filename', and to free it when it is done. This is what the normal
users want, and it simplifies and streamlines their error handling.
The controlled lifetime of the executable name also fixes a
use-after-free problem with the trace_sched_process_exec tracepoint: the
lifetime of the passed-in string for kernel users was not at all
obvious, and the user-mode helper code used UMH_WAIT_EXEC to serialize
the pathname allocation lifetime with the execve() having finished,
which in turn meant that the trace point that happened after
mm_release() of the old process VM ended up using already free'd memory.
To solve the kernel string lifetime issue, this simply introduces
"getname_kernel()" that works like the normal user-space getname()
function, except with the source coming from kernel memory.
As Oleg points out, this also means that we could drop the tcomm[] array
from 'struct linux_binprm', since the pathname lifetime now covers
setup_new_exec(). That would be a separate cleanup.
Reported-by: Igor Zhbanov <i.zhbanov@samsung.com>
Tested-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull timer/dynticks updates from Ingo Molnar:
"This tree contains misc dynticks updates: a fix and three cleanups"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/nohz: Fix overflow error in scheduler_tick_max_deferment()
nohz_full: fix code style issue of tick_nohz_full_stop_tick
nohz: Get timekeeping max deferment outside jiffies_lock
tick: Rename tick_check_idle() to tick_irq_enter()
Pull core debug changes from Ingo Molnar:
"This contains mostly kernel debugging related updates:
- make hung_task detection more configurable to distros
- add final bits for x86 UV NMI debugging, with related KGDB changes
- update the mailing-list of MAINTAINERS entries I'm involved with"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
hung_task: Display every hung task warning
sysctl: Add neg_one as a standard constraint
x86/uv/nmi, kgdb/kdb: Fix UV NMI handler when KDB not configured
x86/uv/nmi: Fix Sparse warnings
kgdb/kdb: Fix no KDB config problem
MAINTAINERS: Restore "L: linux-kernel@vger.kernel.org" entries
Pull core block IO changes from Jens Axboe:
"The major piece in here is the immutable bio_ve series from Kent, the
rest is fairly minor. It was supposed to go in last round, but
various issues pushed it to this release instead. The pull request
contains:
- Various smaller blk-mq fixes from different folks. Nothing major
here, just minor fixes and cleanups.
- Fix for a memory leak in the error path in the block ioctl code
from Christian Engelmayer.
- Header export fix from CaiZhiyong.
- Finally the immutable biovec changes from Kent Overstreet. This
enables some nice future work on making arbitrarily sized bios
possible, and splitting more efficient. Related fixes to immutable
bio_vecs:
- dm-cache immutable fixup from Mike Snitzer.
- btrfs immutable fixup from Muthu Kumar.
- bio-integrity fix from Nic Bellinger, which is also going to stable"
* 'for-3.14/core' of git://git.kernel.dk/linux-block: (44 commits)
xtensa: fixup simdisk driver to work with immutable bio_vecs
block/blk-mq-cpu.c: use hotcpu_notifier()
blk-mq: for_each_* macro correctness
block: Fix memory leak in rw_copy_check_uvector() handling
bio-integrity: Fix bio_integrity_verify segment start bug
block: remove unrelated header files and export symbol
blk-mq: uses page->list incorrectly
blk-mq: use __smp_call_function_single directly
btrfs: fix missing increment of bi_remaining
Revert "block: Warn and free bio if bi_end_io is not set"
block: Warn and free bio if bi_end_io is not set
blk-mq: fix initializing request's start time
block: blk-mq: don't export blk_mq_free_queue()
block: blk-mq: make blk_sync_queue support mq
block: blk-mq: support draining mq queue
dm cache: increment bi_remaining when bi_end_io is restored
block: fixup for generic bio chaining
block: Really silence spurious compiler warnings
block: Silence spurious compiler warnings
block: Kill bio_pair_split()
...
Pull vfs updates from Al Viro:
"Assorted stuff; the biggest pile here is Christoph's ACL series. Plus
assorted cleanups and fixes all over the place...
There will be another pile later this week"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (43 commits)
__dentry_path() fixes
vfs: Remove second variable named error in __dentry_path
vfs: Is mounted should be testing mnt_ns for NULL or error.
Fix race when checking i_size on direct i/o read
hfsplus: remove can_set_xattr
nfsd: use get_acl and ->set_acl
fs: remove generic_acl
nfs: use generic posix ACL infrastructure for v3 Posix ACLs
gfs2: use generic posix ACL infrastructure
jfs: use generic posix ACL infrastructure
xfs: use generic posix ACL infrastructure
reiserfs: use generic posix ACL infrastructure
ocfs2: use generic posix ACL infrastructure
jffs2: use generic posix ACL infrastructure
hfsplus: use generic posix ACL infrastructure
f2fs: use generic posix ACL infrastructure
ext2/3/4: use generic posix ACL infrastructure
btrfs: use generic posix ACL infrastructure
fs: make posix_acl_create more useful
fs: make posix_acl_chmod more useful
...
vsnprintf() may let 'r' larger than sizeof(buf), in this case, if 'r' is
also less than "vmcoreinfo_max_size - vmcoreinfo_size" (left size of
destination buffer), next memcpy() will read the unexpected addresses.
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull tracing fixes from Steven Rostedt:
"The first two patches fix the debugfs README file to reflect better
the new features added to 3.14.
The third patch is a minor bugfix to the trace_puts() functions that
will crash the system if a developer adds one before the tracing
system is setup. It also affects trace_printk() if it has no
arguments, as the code will convert it to a trace_puts() as well.
Note, this bug will not affect unmodified kernels, as trace_printk()
and trace_puts() should only be used by developers for testing"
* tag 'trace-fixes-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Check if tracing is enabled in trace_puts()
tracing: Fix formatting of trace README file
tracing/README: Add event file usage to tracing mini-HOWTO
Pull scheduler fixes from Ingo Molnar:
"A couple of regression fixes mostly hitting virtualized setups, but
also some bare metal systems"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/x86/tsc: Initialize multiplier to 0
sched/clock: Fixup early initialization
sched/preempt/x86: Fix voluntary preempt for x86
Revert "sched: Fix sleep time double accounting in enqueue entity"
When khungtaskd detects hung tasks, it prints out
backtraces from a number of those tasks.
Limiting the number of backtraces being printed
out can result in the user not seeing the information
necessary to debug the issue. The hung_task_warnings
sysctl controls this feature.
This patch makes it possible for hung_task_warnings
to accept a special value to print an unlimited
number of backtraces when khungtaskd detects hung
tasks.
The special value is -1. To use this value it is
necessary to change types from ulong to int.
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: oleg@redhat.com
Link: http://lkml.kernel.org/r/1390239253-24030-3-git-send-email-atomlin@redhat.com
[ Build warning fix. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
rcu_dereference_check_fdtable() looks very wrong,
1. rcu_my_thread_group_empty() was added by 844b9a8707 "vfs: fix
RCU-lockdep false positive due to /proc" but it doesn't really
fix the problem. A CLONE_THREAD (without CLONE_FILES) task can
hit the same race with get_files_struct().
And otoh rcu_my_thread_group_empty() can suppress the correct
warning if the caller is the CLONE_FILES (without CLONE_THREAD)
task.
2. files->count == 1 check is not really right too. Even if this
files_struct is not shared it is not safe to access it lockless
unless the caller is the owner.
Otoh, this check is sub-optimal. files->count == 0 always means
it is safe to use it lockless even if files != current->files,
but put_files_struct() has to take rcu_read_lock(). See the next
patch.
This patch removes the buggy checks and turns fcheck_files() into
__fcheck_files() which uses rcu_dereference_raw(), the "unshared"
callers, fget_light() and fget_raw_light(), can use it to avoid
the warning from RCU-lockdep.
fcheck_files() is trivially reimplemented as rcu_lockdep_assert()
plus __fcheck_files().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull ACPI and power management updates from Rafael Wysocki:
"As far as the number of commits goes, the top spot belongs to ACPI
this time with cpufreq in the second position and a handful of PM
core, PNP and cpuidle updates. They are fixes and cleanups mostly, as
usual, with a couple of new features in the mix.
The most visible change is probably that we will create struct
acpi_device objects (visible in sysfs) for all devices represented in
the ACPI tables regardless of their status and there will be a new
sysfs attribute under those objects allowing user space to check that
status via _STA.
Consequently, ACPI device eject or generally hot-removal will not
delete those objects, unless the table containing the corresponding
namespace nodes is unloaded, which is extremely rare. Also ACPI
container hotplug will be handled quite a bit differently and cpufreq
will support CPU boost ("turbo") generically and not only in the
acpi-cpufreq driver.
Specifics:
- ACPI core changes to make it create a struct acpi_device object for
every device represented in the ACPI tables during all namespace
scans regardless of the current status of that device. In
accordance with this, ACPI hotplug operations will not delete those
objects, unless the underlying ACPI tables go away.
- On top of the above, new sysfs attribute for ACPI device objects
allowing user space to check device status by triggering the
execution of _STA for its ACPI object. From Srinivas Pandruvada.
- ACPI core hotplug changes reducing code duplication, integrating
the PCI root hotplug with the core and reworking container hotplug.
- ACPI core simplifications making it use ACPI_COMPANION() in the
code "glueing" ACPI device objects to "physical" devices.
- ACPICA update to upstream version 20131218. This adds support for
the DBG2 and PCCT tables to ACPICA, fixes some bugs and improves
debug facilities. From Bob Moore, Lv Zheng and Betty Dall.
- Init code change to carry out the early ACPI initialization
earlier. That should allow us to use ACPI during the timekeeping
initialization and possibly to simplify the EFI initialization too.
From Chun-Yi Lee.
- Clenups of the inclusions of ACPI headers in many places all over
from Lv Zheng and Rashika Kheria (work in progress).
- New helper for ACPI _DSM execution and rework of the code in
drivers that uses _DSM to execute it via the new helper. From
Jiang Liu.
- New Win8 OSI blacklist entries from Takashi Iwai.
- Assorted ACPI fixes and cleanups from Al Stone, Emil Goode, Hanjun
Guo, Lan Tianyu, Masanari Iida, Oliver Neukum, Prarit Bhargava,
Rashika Kheria, Tang Chen, Zhang Rui.
- intel_pstate driver updates, including proper Baytrail support,
from Dirk Brandewie and intel_pstate documentation from Ramkumar
Ramachandra.
- Generic CPU boost ("turbo") support for cpufreq from Lukasz
Majewski.
- powernow-k6 cpufreq driver fixes from Mikulas Patocka.
- cpufreq core fixes and cleanups from Viresh Kumar, Jane Li, Mark
Brown.
- Assorted cpufreq drivers fixes and cleanups from Anson Huang, John
Tobias, Paul Bolle, Paul Walmsley, Sachin Kamat, Shawn Guo, Viresh
Kumar.
- cpuidle cleanups from Bartlomiej Zolnierkiewicz.
- Support for hibernation APM events from Bin Shi.
- Hibernation fix to avoid bringing up nonboot CPUs with ACPI EC
disabled during thaw transitions from Bjørn Mork.
- PM core fixes and cleanups from Ben Dooks, Leonardo Potenza, Ulf
Hansson.
- PNP subsystem fixes and cleanups from Dmitry Torokhov, Levente
Kurusa, Rashika Kheria.
- New tool for profiling system suspend from Todd E Brandt and a
cpupower tool cleanup from One Thousand Gnomes"
* tag 'pm+acpi-3.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (153 commits)
thermal: exynos: boost: Automatic enable/disable of BOOST feature (at Exynos4412)
cpufreq: exynos4x12: Change L0 driver data to CPUFREQ_BOOST_FREQ
Documentation: cpufreq / boost: Update BOOST documentation
cpufreq: exynos: Extend Exynos cpufreq driver to support boost
cpufreq / boost: Kconfig: Support for software-managed BOOST
acpi-cpufreq: Adjust the code to use the common boost attribute
cpufreq: Add boost frequency support in core
intel_pstate: Add trace point to report internal state.
cpufreq: introduce cpufreq_generic_get() routine
ARM: SA1100: Create dummy clk_get_rate() to avoid build failures
cpufreq: stats: create sysfs entries when cpufreq_stats is a module
cpufreq: stats: free table and remove sysfs entry in a single routine
cpufreq: stats: remove hotplug notifiers
cpufreq: stats: handle cpufreq_unregister_driver() and suspend/resume properly
cpufreq: speedstep: remove unused speedstep_get_state
platform: introduce OF style 'modalias' support for platform bus
PM / tools: new tool for suspend/resume performance optimization
ACPI: fix module autoloading for ACPI enumerated devices
ACPI: add module autoloading support for ACPI enumerated devices
ACPI: fix create_modalias() return value handling
...
Merge second patch-bomb from Andrew Morton:
- various misc bits
- the rest of MM
- add generic fixmap.h, use it
- backlight updates
- dynamic_debug updates
- printk() updates
- checkpatch updates
- binfmt_elf
- ramfs
- init/
- autofs4
- drivers/rtc
- nilfs
- hfsplus
- Documentation/
- coredump
- procfs
- fork
- exec
- kexec
- kdump
- partitions
- rapidio
- rbtree
- userns
- memstick
- w1
- decompressors
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (197 commits)
lib/decompress_unlz4.c: always set an error return code on failures
romfs: fix returm err while getting inode in fill_super
drivers/w1/masters/w1-gpio.c: add strong pullup emulation
drivers/memstick/host/rtsx_pci_ms.c: fix ms card data transfer bug
userns: relax the posix_acl_valid() checks
arch/sh/kernel/dwarf.c: use rbtree postorder iteration helper instead of solution using repeated rb_erase()
fs-ext3-use-rbtree-postorder-iteration-helper-instead-of-opencoding-fix
fs/ext3: use rbtree postorder iteration helper instead of opencoding
fs/jffs2: use rbtree postorder iteration helper instead of opencoding
fs/ext4: use rbtree postorder iteration helper instead of opencoding
fs/ubifs: use rbtree postorder iteration helper instead of opencoding
net/netfilter/ipset/ip_set_hash_netiface.c: use rbtree postorder iteration instead of opencoding
rbtree/test: test rbtree_postorder_for_each_entry_safe()
rbtree/test: move rb_node to the middle of the test struct
rapidio: add modular rapidio core build into powerpc and mips branches
partitions/efi: complete documentation of gpt kernel param purpose
kdump: add /sys/kernel/vmcoreinfo ABI documentation
kdump: fix exported size of vmcoreinfo note
kexec: add sysctl to disable kexec_load
fs/exec.c: call arch_pick_mmap_layout() only once
...
