- 17 Apr, 2015 40 commits
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Davidlohr Bueso authored
The mm->exe_file is currently serialized with mmap_sem (shared) in order to both safely (1) read the file and (2) compute the realpath by calling tomoyo_realpath_from_path, making it an absolute overkill. Good users will, on the other hand, make use of the more standard get_mm_exe_file(), requiring only holding the mmap_sem to read the value, and relying on reference [akpm@linux-foundation.org: coding-style fixes] Signed-off-by:
Davidlohr Bueso <dbueso@suse.de> Acked-by:
Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: James Morris <jmorris@namei.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Davidlohr Bueso authored
In the future mm->exe_file will be done without mmap_sem serialization, thus isolate and reorganize the related code to make the transition easier. Good users will, make use of the more standard get_mm_exe_file(), requiring only holding the mmap_sem to read the value, and relying on reference counting to make sure that the exe file won't dissappear underneath us while getting the dcookie. Signed-off-by:
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Davidlohr Bueso authored
sync_buffer() needs the mmap_sem for two distinct operations, both only occurring upon user context switch handling: 1) Dealing with the exe_file. 2) Adding the dcookie data as we need to lookup the vma that backs it. This is done via add_sample() and add_data(). This patch isolates 1), for it will no longer need the mmap_sem for serialization. However, for now, make of the more standard get_mm_exe_file(), requiring only holding the mmap_sem to read the value, and relying on reference counting to make sure that the exe file won't dissappear underneath us while doing the get dcookie. As a consequence, for 2) we move the mmap_sem locking into where we really need it, in lookup_dcookie(). The benefits are twofold: reduce mmap_sem hold times, and cleaner code. [akpm@linux-foundation.org: export get_mm_exe_file for arch/x86/oprofile/oprofile.ko] Signed-off-by:
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Joshua Kinard authored
This modifies the IP32 (SGI O2) platform and reset code to utilize the new rtc-ds1685 driver. The old mc146818rtc.h header is removed and ip32_defconfig is updated as well. Signed-off-by:
Joshua Kinard <kumba@gentoo.org> Acked-by:
Ralf Baechle <ralf@linux-mips.org> Cc: Alessandro Zummo <a.zummo@towertech.it> Signed-off-by:
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Andrew Morton authored
Cc: Yalin Wang <yalin.wang@sonymobile.com> Cc: Russell King <linux@arm.linux.org.uk> Signed-off-by:
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Kees Cook authored
Switch to using the newly created asm-generic/seccomp.h for the seccomp strict mode syscall definitions. The obsolete sigreturn syscall override is retained in 32-bit mode, and the ia32 syscall overrides are used in the compat case. Remaining definitions were identical. Signed-off-by:
Kees Cook <keescook@chromium.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
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Kees Cook authored
Switch to using the newly created asm-generic/seccomp.h for the seccomp strict mode syscall definitions. The obsolete sigreturn in COMPAT mode is retained as an override. Remaining definitions are identical. Also corrected missing #define for header reinclusion protection. Signed-off-by:
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Kees Cook authored
Switch to using the newly created asm-generic/seccomp.h for the seccomp strict mode syscall definitions. The obsolete sigreturn in COMPAT mode is retained as an override. Remaining definitions are identical, though they incorrectly appeared in uapi, which has been corrected. Signed-off-by:
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Kees Cook authored
Switch to using the newly created asm-generic/seccomp.h for the seccomp strict mode syscall definitions. Definitions were identical. Signed-off-by:
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Kees Cook authored
Switch to using the newly created asm-generic/seccomp.h for the seccomp strict mode syscall definitions. COMPAT definitions retain their overrides and the remaining definitions were identical. Signed-off-by:
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Kees Cook authored
Switch to using the newly created asm-generic/seccomp.h for the seccomp strict mode syscall definitions. Since microblaze is 32-bit, the COMPAT seccomp defines are unused and can be dropped. The obsolete sigreturn for seccomp strict mode is retained as an override. Remaining definitions are identical. Signed-off-by:
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Kees Cook authored
Switch to using the newly created asm-generic/seccomp.h for the seccomp strict mode syscall definitions. Definitions were identical. Signed-off-by:
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Kees Cook authored
Most architectures don't need to do much special for the strict-mode seccomp syscall entries. Remove the redundant headers and reduce the others. This patch (of 8): Some architectures may need to override the compat sigreturn definition, as is already possible in the non-compat case. Signed-off-by:
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Davidlohr Bueso authored
print_task_path_n_nm() is local to this file, its only user being show_regs(). Mark the function static and avoid the EXPORT_SYMBOL. Signed-off-by:
Vineet Gupta <vgupta@synoipsys.com> Signed-off-by:
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Michal Simek authored
It is better to use macros which are already available because then there is just one location which needs to be change. [akpm@linux-foundation.org: move IS_ENABLED definition to after the IS_BUILTIN and IS_MODULE definitions] Signed-off-by:
Michal Simek <michal.simek@xilinx.com> Signed-off-by:
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Dan Carpenter authored
Using the indenting we can see the curly braces were obviously intended. This is a static checker fix, but my guess is that we don't read enough bytes, because we don't calculate "t_len" correctly. Fixes: f1d82698 ('memstick: use fully asynchronous request processing') Signed-off-by:
Dan Carpenter <dan.carpenter@oracle.com> Cc: Alex Dubov <oakad@yahoo.com> Signed-off-by:
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Sanidhya Kashyap authored
In case of failed memory allocation, the return should be ENOMEM instead of ENOSPC. Return -EIO when sb_bread() fails. Signed-off-by:
Sanidhya Kashyap <sanidhya.gatech@gmail.com> Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk> Signed-off-by:
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Jiri Slaby authored
This kthread is not loop at all due to break at the end of the loop. Make that function linear, with no while loop. And remove an unnecessary cast. Signed-off-by:
Jiri Slaby <jslaby@suse.cz> Cc: Anil Gurumurthy <anil.gurumurthy@qlogic.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by:
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Sanidhya Kashyap authored
There is a possibility of kstrdup() failure upon memory pressure. Therefore, returning ENOMEM even for new_opts. [akpm@linux-foundation.org: cleanup] Signed-off-by:
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Fabian Frederick authored
Replace mount option test by affs_test_opt(). Signed-off-by:
Fabian Frederick <fabf@skynet.be> Signed-off-by:
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Fabian Frederick authored
Replace direct mount option assignation by affs_set_opt() macro. Signed-off-by:
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Fabian Frederick authored
Add clear/set/test affs mount option macros. Signed-off-by:
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Fabian Frederick authored
Currently, affs still uses direct access on mount_options. This patch prepares to use affs_clear/set/test_opt() like other filesystems. Signed-off-by:
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Sanidhya Kashyap authored
Fix the wrong values returned by various functions such as EIO and ENOMEM. Signed-off-by:
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Andrey Ryabinin authored
gcov profiling if enabled with other heavy compile-time instrumentation like KASan could trigger following softlockups: NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:1] Modules linked in: irq event stamp: 22823276 hardirqs last enabled at (22823275): [<ffffffff86e8d10d>] mutex_lock_nested+0x7d9/0x930 hardirqs last disabled at (22823276): [<ffffffff86e9521d>] apic_timer_interrupt+0x6d/0x80 softirqs last enabled at (22823172): [<ffffffff811ed969>] __do_softirq+0x4db/0x729 softirqs last disabled at (22823167): [<ffffffff811edfcf>] irq_exit+0x7d/0x15b CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 3.19.0-05245-gbb33326-dirty #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5.1-0-g8936dbb-20141113_115728-nilsson.home.kraxel.org 04/01/2014 task: ffff88006cba8000 ti: ffff88006cbb0000 task.ti: ffff88006cbb0000 RIP: kasan_mem_to_shadow+0x1e/0x1f Call Trace: strcmp+0x28/0x70 get_node_by_name+0x66/0x99 gcov_event+0x4f/0x69e gcov_enable_events+0x54/0x7b gcov_fs_init+0xf8/0x134 do_one_initcall+0x1b2/0x288 kernel_init_freeable+0x467/0x580 kernel_init+0x15/0x18b ret_from_fork+0x7c/0xb0 Kernel panic - not syncing: softlockup: hung tasks Fix this by sticking cond_resched() in gcov_enable_events(). Signed-off-by:Andrey Ryabinin <a.ryabinin@samsung.com> Reported-by:
Fengguang Wu <fengguang.wu@intel.com> Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by:
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Heinrich Schuchardt authored
When converting unsigned long to int overflows may occur. These currently are not detected when writing to the sysctl file system. E.g. on a system where int has 32 bits and long has 64 bits echo 0x800001234 > /proc/sys/kernel/threads-max has the same effect as echo 0x1234 > /proc/sys/kernel/threads-max The patch adds the missing check in do_proc_dointvec_conv. With the patch an overflow will result in an error EINVAL when writing to the the sysctl file system. Signed-off-by:
Heinrich Schuchardt <xypron.glpk@gmx.de> Signed-off-by:
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Sergey Senozhatsky authored
cpumask_next_and() is looking for cpumask_next() in src1 in a loop and tests if found cpu is also present in src2. remove that loop, perform cpumask_and() of src1 and src2 first and use that new mask to find cpumask_next(). Apart from removing while loop, ./bloat-o-meter on x86_64 shows add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-8 (-8) function old new delta cpumask_next_and 62 54 -8 Signed-off-by:
Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Amir Vadai <amirv@mellanox.com> Signed-off-by:
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Kirill Tkhai authored
We set sig->notify_count = -1 between RELEASE and ACQUIRE operations: spin_unlock_irq(lock); ... if (!thread_group_leader(tsk)) { ... for (;;) { sig->notify_count = -1; write_lock_irq(&tasklist_lock); There are no restriction on it so other processors may see this STORE mixed with other STOREs in both areas limited by the spinlocks. Probably, it may be reordered with the above sig->group_exit_task = tsk; sig->notify_count = zap_other_threads(tsk); in some way. Set it under tasklist_lock locked to be sure nothing will be reordered. Signed-off-by:Kirill Tkhai <ktkhai@parallels.com> Acked-by:
Oleg Nesterov <oleg@redhat.com> Signed-off-by:
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Davidlohr Bueso authored
Oleg cleverly suggested using xchg() to set the new mm->exe_file instead of calling set_mm_exe_file() which requires some form of serialization -- mmap_sem in this case. For archs that do not have atomic rmw instructions we still fallback to a spinlock alternative, so this should always be safe. As such, we only need the mmap_sem for looking up the backing vm_file, which can be done sharing the lock. Naturally, this means we need to manually deal with both the new and old file reference counting, and we need not worry about the MMF_EXE_FILE_CHANGED bits, which can probably be deleted in the future anyway. Signed-off-by:
Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by:
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Konstantin Khlebnikov authored
This patch removes mm->mmap_sem from mm->exe_file read side. Also it kills dup_mm_exe_file() and moves exe_file duplication into dup_mmap() where both mmap_sems are locked. [akpm@linux-foundation.org: fix comment typo] Signed-off-by:
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Heinrich Schuchardt authored
File /proc/sys/kernel/threads-max controls the maximum number of threads that can be created using fork(). [akpm@linux-foundation.org: fix typo, per Guenter] Signed-off-by:
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Heinrich Schuchardt authored
Users can change the maximum number of threads by writing to /proc/sys/kernel/threads-max. With the patch the value entered is checked against the same limits that apply when fork_init is called. Signed-off-by:
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Heinrich Schuchardt authored
PAGE_SIZE is not guaranteed to be equal to or less than 8 times the THREAD_SIZE. E.g. architecture hexagon may have page size 1M and thread size 4096. This would lead to a division by zero in the calculation of max_threads. With 32-bit calculation there is no solution which delivers valid results for all possible combinations of the parameters. The code is only called once. Hence a 64-bit calculation can be used as solution. [akpm@linux-foundation.org: use clamp_t(), per Oleg] Signed-off-by:
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Heinrich Schuchardt authored
PAGE_SIZE is not guaranteed to be equal to or less than 8 times the THREAD_SIZE. E.g. architecture hexagon may have page size 1M and thread size 4096. This would lead to a division by zero in the calculation of max_threads. With this patch the buggy code is moved to a separate function set_max_threads. The error is not fixed. After fixing the problem in a separate patch the new function can be reused to adjust max_threads after adding or removing memory. Argument mempages of function fork_init() is removed as totalram_pages is an exported symbol. The creation of separate patches for refactoring to a new function and for fixing the logic was suggested by Ingo Molnar. Signed-off-by:
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Jean Delvare authored
The comment explaining what value max_threads is set to is outdated. The maximum memory consumption ratio for thread structures was 1/2 until February 2002, then it was briefly changed to 1/16 before being set to 1/8 which we still use today. The comment was never updated to reflect that change, it's about time. Signed-off-by:
Jean Delvare <jdelvare@suse.de> Signed-off-by:
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Michal Hocko authored
copy_process will report any failure in alloc_pid as ENOMEM currently which is misleading because the pid allocation might fail not only when the memory is short but also when the pid space is consumed already. The current man page even mentions this case: : EAGAIN : : A system-imposed limit on the number of threads was encountered. : There are a number of limits that may trigger this error: the : RLIMIT_NPROC soft resource limit (set via setrlimit(2)), which : limits the number of processes and threads for a real user ID, was : reached; the kernel's system-wide limit on the number of processes : and threads, /proc/sys/kernel/threads-max, was reached (see : proc(5)); or the maximum number of PIDs, /proc/sys/kernel/pid_max, : was reached (see proc(5)). so the current behavior is also incorrect wrt. documentation. POSIX man page also suggest returing EAGAIN when the process count limit is reached. This patch simply propagates error code from alloc_pid and makes sure we return -EAGAIN due to reservation failure. This will make behavior of fork closer to both our documentation and POSIX. alloc_pid might alsoo fail when the reaper in the pid namespace is dead (the namespace basically disallows all new processes) and there is no good error code which would match documented ones. We have traditionally returned ENOMEM for this case which is misleading as well but as per Eric W. Biederman this behavior is documented in man pid_namespaces(7) : If the "init" process of a PID namespace terminates, the kernel : terminates all of the processes in the namespace via a SIGKILL signal. : This behavior reflects the fact that the "init" process is essential for : the correct operation of a PID namespace. In this case, a subsequent : fork(2) into this PID namespace will fail with the error ENOMEM; it is : not possible to create a new processes in a PID namespace whose "init" : process has terminated. and introducing a new error code would be too risky so let's stick to ENOMEM for this case. Signed-off-by:
Michal Hocko <mhocko@suse.cz> Cc: Oleg Nesterov <oleg@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Signed-off-by:
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Vladimir Davydov authored
Sending SI_TKILL from rt_[tg]sigqueueinfo was deprecated, so now we issue a warning on the first attempt of doing it. We use WARN_ON_ONCE, which is not informative and, what is worse, taints the kernel, making the trinity syscall fuzzer complain false-positively from time to time. It does not look like we need this warning at all, because the behaviour changed quite a long time ago (2.6.39), and if an application relies on the old API, it gets EPERM anyway and can issue a warning by itself. So let us zap the warning in kernel. Signed-off-by:
Vladimir Davydov <vdavydov@parallels.com> Acked-by:
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Oleg Nesterov authored
ptrace_detach() re-checks ->ptrace under tasklist lock and calls release_task() if __ptrace_detach() returns true. This was needed because the __TASK_TRACED tracee could be killed/untraced, and it could even pass exit_notify() before we take tasklist_lock. But this is no longer possible after 9899d11f "ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL". We can turn these checks into WARN_ON() and remove release_task(). While at it, document the setting of child->exit_code. Signed-off-by:
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Oleg Nesterov authored
ptrace_resume() is called when the tracee is still __TASK_TRACED. We set tracee->exit_code and then wake_up_state() changes tracee->state. If the tracer's sub-thread does wait() in between, task_stopped_code(ptrace => T) wrongly looks like another report from tracee. This confuses debugger, and since wait_task_stopped() clears ->exit_code the tracee can miss a signal. Test-case: #include <stdio.h> #include <unistd.h> #include <sys/wait.h> #include <sys/ptrace.h> #include <pthread.h> #include <assert.h> int pid; void *waiter(void *arg) { int stat; for (;;) { assert(pid == wait(&stat)); assert(WIFSTOPPED(stat)); if (WSTOPSIG(stat) == SIGHUP) continue; assert(WSTOPSIG(stat) == SIGCONT); printf("ERR! extra/wrong report:%x\n", stat); } } int main(void) { pthread_t thread; pid = fork(); if (!pid) { assert(ptrace(PTRACE_TRACEME, 0,0,0) == 0); for (;;) kill(getpid(), SIGHUP); } assert(pthread_create(&thread, NULL, waiter, NULL) == 0); for (;;) ptrace(PTRACE_CONT, pid, 0, SIGCONT); return 0; } Note for stable: the bug is very old, but without 9899d11f "ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL" the fix should use lock_task_sighand(child). Signed-off-by:Pavel Labath <labath@google.com> Tested-by:
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Alexander Kuleshov authored
Signed-off-by:
Alexander Kuleshov <kuleshovmail@gmail.com> Acked-by:
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Signed-off-by:
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