1. 17 2月, 2015 2 次提交
  2. 06 2月, 2015 1 次提交
  3. 15 1月, 2015 2 次提交
  4. 12 1月, 2015 1 次提交
  5. 09 1月, 2015 1 次提交
  6. 07 1月, 2015 1 次提交
  7. 29 12月, 2014 1 次提交
  8. 23 12月, 2014 1 次提交
  9. 19 12月, 2014 1 次提交
  10. 17 12月, 2014 3 次提交
  11. 16 12月, 2014 2 次提交
  12. 14 12月, 2014 4 次提交
    • M
      virtio_pci: add VIRTIO_PCI_NO_LEGACY · 0dce3771
      Michael S. Tsirkin 提交于
      Add macro to disable all legacy register defines.
      Helpful to make sure legacy macros don't leak
      through into modern code.
      Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      0dce3771
    • M
      ipc/msg: increase MSGMNI, remove scaling · 0050ee05
      Manfred Spraul 提交于
      SysV can be abused to allocate locked kernel memory.  For most systems, a
      small limit doesn't make sense, see the discussion with regards to SHMMAX.
      
      Therefore: increase MSGMNI to the maximum supported.
      
      And: If we ignore the risk of locking too much memory, then an automatic
      scaling of MSGMNI doesn't make sense.  Therefore the logic can be removed.
      
      The code preserves auto_msgmni to avoid breaking any user space applications
      that expect that the value exists.
      
      Notes:
      1) If an administrator must limit the memory allocations, then he can set
      MSGMNI as necessary.
      
      Or he can disable sysv entirely (as e.g. done by Android).
      
      2) MSGMAX and MSGMNB are intentionally not increased, as these values are used
      to control latency vs. throughput:
      If MSGMNB is large, then msgsnd() just returns and more messages can be queued
      before a task switch to a task that calls msgrcv() is forced.
      
      [akpm@linux-foundation.org: coding-style fixes]
      Signed-off-by: NManfred Spraul <manfred@colorfullife.com>
      Cc: Davidlohr Bueso <dave@stgolabs.net>
      Cc: Rafael Aquini <aquini@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      0050ee05
    • M
      ipc/sem.c: increase SEMMSL, SEMMNI, SEMOPM · e843e7d2
      Manfred Spraul 提交于
      a)
      
      SysV can be abused to allocate locked kernel memory.  For most systems, a
      small limit doesn't make sense, see the discussion with regards to SHMMAX.
      
      Therefore: Increase the sysv sem limits so that all known applications
      will work with these defaults.
      
      b)
      
      With regards to the maximum supported:
      Some of the specified hard limits are not correct anymore, therefore the
      patch updates the documentation.
      
      - SEMMNI must stay below IPCMNI, which is 32768.
        As for SHMMAX: Stay a bit below this limit.
      
      - SEMMSL was limited to 8k, to ensure that the kmalloc for the kernel array
        was limited to 16 kB (order=2)
      
        This doesn't apply anymore:
         - the allocation size isn't sizeof(short)*nsems anymore.
         - ipc_alloc falls back to vmalloc
      
      - SEMOPM should stay below 1000, to limit the kmalloc in semtimedop() to an
        order=1 allocation.
        Therefore: Leave it at 500 (order=0 allocation).
      
      Note:
      If an administrator must limit the memory allocations, then he can set the
      values as necessary.
      
      Or he can disable sysv entirely (as e.g. done by Android).
      Signed-off-by: NManfred Spraul <manfred@colorfullife.com>
      Cc: Davidlohr Bueso <dave@stgolabs.net>
      Acked-by: NRafael Aquini <aquini@redhat.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e843e7d2
    • D
      syscalls: implement execveat() system call · 51f39a1f
      David Drysdale 提交于
      This patchset adds execveat(2) for x86, and is derived from Meredydd
      Luff's patch from Sept 2012 (https://lkml.org/lkml/2012/9/11/528).
      
      The primary aim of adding an execveat syscall is to allow an
      implementation of fexecve(3) that does not rely on the /proc filesystem,
      at least for executables (rather than scripts).  The current glibc version
      of fexecve(3) is implemented via /proc, which causes problems in sandboxed
      or otherwise restricted environments.
      
      Given the desire for a /proc-free fexecve() implementation, HPA suggested
      (https://lkml.org/lkml/2006/7/11/556) that an execveat(2) syscall would be
      an appropriate generalization.
      
      Also, having a new syscall means that it can take a flags argument without
      back-compatibility concerns.  The current implementation just defines the
      AT_EMPTY_PATH and AT_SYMLINK_NOFOLLOW flags, but other flags could be
      added in future -- for example, flags for new namespaces (as suggested at
      https://lkml.org/lkml/2006/7/11/474).
      
      Related history:
       - https://lkml.org/lkml/2006/12/27/123 is an example of someone
         realizing that fexecve() is likely to fail in a chroot environment.
       - http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=514043 covered
         documenting the /proc requirement of fexecve(3) in its manpage, to
         "prevent other people from wasting their time".
       - https://bugzilla.redhat.com/show_bug.cgi?id=241609 described a
         problem where a process that did setuid() could not fexecve()
         because it no longer had access to /proc/self/fd; this has since
         been fixed.
      
      This patch (of 4):
      
      Add a new execveat(2) system call.  execveat() is to execve() as openat()
      is to open(): it takes a file descriptor that refers to a directory, and
      resolves the filename relative to that.
      
      In addition, if the filename is empty and AT_EMPTY_PATH is specified,
      execveat() executes the file to which the file descriptor refers.  This
      replicates the functionality of fexecve(), which is a system call in other
      UNIXen, but in Linux glibc it depends on opening "/proc/self/fd/<fd>" (and
      so relies on /proc being mounted).
      
      The filename fed to the executed program as argv[0] (or the name of the
      script fed to a script interpreter) will be of the form "/dev/fd/<fd>"
      (for an empty filename) or "/dev/fd/<fd>/<filename>", effectively
      reflecting how the executable was found.  This does however mean that
      execution of a script in a /proc-less environment won't work; also, script
      execution via an O_CLOEXEC file descriptor fails (as the file will not be
      accessible after exec).
      
      Based on patches by Meredydd Luff.
      Signed-off-by: NDavid Drysdale <drysdale@google.com>
      Cc: Meredydd Luff <meredydd@senatehouse.org>
      Cc: Shuah Khan <shuah.kh@samsung.com>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Arnd Bergmann <arnd@arndb.de>
      Cc: Rich Felker <dalias@aerifal.cx>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Michael Kerrisk <mtk.manpages@gmail.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      51f39a1f
  13. 12 12月, 2014 1 次提交
  14. 11 12月, 2014 2 次提交
    • A
      take the targets of /proc/*/ns/* symlinks to separate fs · e149ed2b
      Al Viro 提交于
      New pseudo-filesystem: nsfs.  Targets of /proc/*/ns/* live there now.
      It's not mountable (not even registered, so it's not in /proc/filesystems,
      etc.).  Files on it *are* bindable - we explicitly permit that in do_loopback().
      
      This stuff lives in fs/nsfs.c now; proc_ns_fget() moved there as well.
      get_proc_ns() is a macro now (it's simply returning ->i_private; would
      have been an inline, if not for header ordering headache).
      proc_ns_inode() is an ex-parrot.  The interface used in procfs is
      ns_get_path(path, task, ops) and ns_get_name(buf, size, task, ops).
      
      Dentries and inodes are never hashed; a non-counting reference to dentry
      is stashed in ns_common (removed by ->d_prune()) and reused by ns_get_path()
      if present.  See ns_get_path()/ns_prune_dentry/nsfs_evict() for details
      of that mechanism.
      
      As the result, proc_ns_follow_link() has stopped poking in nd->path.mnt;
      it does nd_jump_link() on a consistent <vfsmount,dentry> pair it gets
      from ns_get_path().
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      e149ed2b
    • P
      kernel: add panic_on_warn · 9e3961a0
      Prarit Bhargava 提交于
      There have been several times where I have had to rebuild a kernel to
      cause a panic when hitting a WARN() in the code in order to get a crash
      dump from a system.  Sometimes this is easy to do, other times (such as
      in the case of a remote admin) it is not trivial to send new images to
      the user.
      
      A much easier method would be a switch to change the WARN() over to a
      panic.  This makes debugging easier in that I can now test the actual
      image the WARN() was seen on and I do not have to engage in remote
      debugging.
      
      This patch adds a panic_on_warn kernel parameter and
      /proc/sys/kernel/panic_on_warn calls panic() in the
      warn_slowpath_common() path.  The function will still print out the
      location of the warning.
      
      An example of the panic_on_warn output:
      
      The first line below is from the WARN_ON() to output the WARN_ON()'s
      location.  After that the panic() output is displayed.
      
          WARNING: CPU: 30 PID: 11698 at /home/prarit/dummy_module/dummy-module.c:25 init_dummy+0x1f/0x30 [dummy_module]()
          Kernel panic - not syncing: panic_on_warn set ...
      
          CPU: 30 PID: 11698 Comm: insmod Tainted: G        W  OE  3.17.0+ #57
          Hardware name: Intel Corporation S2600CP/S2600CP, BIOS RMLSDP.86I.00.29.D696.1311111329 11/11/2013
           0000000000000000 000000008e3f87df ffff88080f093c38 ffffffff81665190
           0000000000000000 ffffffff818aea3d ffff88080f093cb8 ffffffff8165e2ec
           ffffffff00000008 ffff88080f093cc8 ffff88080f093c68 000000008e3f87df
          Call Trace:
           [<ffffffff81665190>] dump_stack+0x46/0x58
           [<ffffffff8165e2ec>] panic+0xd0/0x204
           [<ffffffffa038e05f>] ? init_dummy+0x1f/0x30 [dummy_module]
           [<ffffffff81076b90>] warn_slowpath_common+0xd0/0xd0
           [<ffffffffa038e040>] ? dummy_greetings+0x40/0x40 [dummy_module]
           [<ffffffff81076c8a>] warn_slowpath_null+0x1a/0x20
           [<ffffffffa038e05f>] init_dummy+0x1f/0x30 [dummy_module]
           [<ffffffff81002144>] do_one_initcall+0xd4/0x210
           [<ffffffff811b52c2>] ? __vunmap+0xc2/0x110
           [<ffffffff810f8889>] load_module+0x16a9/0x1b30
           [<ffffffff810f3d30>] ? store_uevent+0x70/0x70
           [<ffffffff810f49b9>] ? copy_module_from_fd.isra.44+0x129/0x180
           [<ffffffff810f8ec6>] SyS_finit_module+0xa6/0xd0
           [<ffffffff8166cf29>] system_call_fastpath+0x12/0x17
      
      Successfully tested by me.
      
      hpa said: There is another very valid use for this: many operators would
      rather a machine shuts down than being potentially compromised either
      functionally or security-wise.
      Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
      Cc: Jonathan Corbet <corbet@lwn.net>
      Cc: Rusty Russell <rusty@rustcorp.com.au>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
      Acked-by: NYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
      Cc: Fabian Frederick <fabf@skynet.be>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      9e3961a0
  15. 10 12月, 2014 5 次提交
  16. 09 12月, 2014 12 次提交