1. 05 2月, 2016 2 次提交
  2. 23 1月, 2016 1 次提交
    • A
      wrappers for ->i_mutex access · 5955102c
      Al Viro 提交于
      parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
      inode_foo(inode) being mutex_foo(&inode->i_mutex).
      
      Please, use those for access to ->i_mutex; over the coming cycle
      ->i_mutex will become rwsem, with ->lookup() done with it held
      only shared.
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      5955102c
  3. 22 1月, 2016 5 次提交
  4. 15 1月, 2016 1 次提交
    • V
      kmemcg: account certain kmem allocations to memcg · 5d097056
      Vladimir Davydov 提交于
      Mark those kmem allocations that are known to be easily triggered from
      userspace as __GFP_ACCOUNT/SLAB_ACCOUNT, which makes them accounted to
      memcg.  For the list, see below:
      
       - threadinfo
       - task_struct
       - task_delay_info
       - pid
       - cred
       - mm_struct
       - vm_area_struct and vm_region (nommu)
       - anon_vma and anon_vma_chain
       - signal_struct
       - sighand_struct
       - fs_struct
       - files_struct
       - fdtable and fdtable->full_fds_bits
       - dentry and external_name
       - inode for all filesystems. This is the most tedious part, because
         most filesystems overwrite the alloc_inode method.
      
      The list is far from complete, so feel free to add more objects.
      Nevertheless, it should be close to "account everything" approach and
      keep most workloads within bounds.  Malevolent users will be able to
      breach the limit, but this was possible even with the former "account
      everything" approach (simply because it did not account everything in
      fact).
      
      [akpm@linux-foundation.org: coding-style fixes]
      Signed-off-by: NVladimir Davydov <vdavydov@virtuozzo.com>
      Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
      Acked-by: NMichal Hocko <mhocko@suse.com>
      Cc: Tejun Heo <tj@kernel.org>
      Cc: Greg Thelen <gthelen@google.com>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Pekka Enberg <penberg@kernel.org>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      5d097056
  5. 09 12月, 2015 1 次提交
    • A
      replace ->follow_link() with new method that could stay in RCU mode · 6b255391
      Al Viro 提交于
      new method: ->get_link(); replacement of ->follow_link().  The differences
      are:
      	* inode and dentry are passed separately
      	* might be called both in RCU and non-RCU mode;
      the former is indicated by passing it a NULL dentry.
      	* when called that way it isn't allowed to block
      and should return ERR_PTR(-ECHILD) if it needs to be called
      in non-RCU mode.
      
      It's a flagday change - the old method is gone, all in-tree instances
      converted.  Conversion isn't hard; said that, so far very few instances
      do not immediately bail out when called in RCU mode.  That'll change
      in the next commits.
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      6b255391
  6. 07 12月, 2015 1 次提交
  7. 07 11月, 2015 1 次提交
  8. 03 11月, 2015 7 次提交
  9. 23 10月, 2015 1 次提交
  10. 11 9月, 2015 1 次提交
  11. 09 9月, 2015 9 次提交
  12. 05 9月, 2015 1 次提交
    • K
      fs: create and use seq_show_option for escaping · a068acf2
      Kees Cook 提交于
      Many file systems that implement the show_options hook fail to correctly
      escape their output which could lead to unescaped characters (e.g.  new
      lines) leaking into /proc/mounts and /proc/[pid]/mountinfo files.  This
      could lead to confusion, spoofed entries (resulting in things like
      systemd issuing false d-bus "mount" notifications), and who knows what
      else.  This looks like it would only be the root user stepping on
      themselves, but it's possible weird things could happen in containers or
      in other situations with delegated mount privileges.
      
      Here's an example using overlay with setuid fusermount trusting the
      contents of /proc/mounts (via the /etc/mtab symlink).  Imagine the use
      of "sudo" is something more sneaky:
      
        $ BASE="ovl"
        $ MNT="$BASE/mnt"
        $ LOW="$BASE/lower"
        $ UP="$BASE/upper"
        $ WORK="$BASE/work/ 0 0
        none /proc fuse.pwn user_id=1000"
        $ mkdir -p "$LOW" "$UP" "$WORK"
        $ sudo mount -t overlay -o "lowerdir=$LOW,upperdir=$UP,workdir=$WORK" none /mnt
        $ cat /proc/mounts
        none /root/ovl/mnt overlay rw,relatime,lowerdir=ovl/lower,upperdir=ovl/upper,workdir=ovl/work/ 0 0
        none /proc fuse.pwn user_id=1000 0 0
        $ fusermount -u /proc
        $ cat /proc/mounts
        cat: /proc/mounts: No such file or directory
      
      This fixes the problem by adding new seq_show_option and
      seq_show_option_n helpers, and updating the vulnerable show_option
      handlers to use them as needed.  Some, like SELinux, need to be open
      coded due to unusual existing escape mechanisms.
      
      [akpm@linux-foundation.org: add lost chunk, per Kees]
      [keescook@chromium.org: seq_show_option should be using const parameters]
      Signed-off-by: NKees Cook <keescook@chromium.org>
      Acked-by: NSerge Hallyn <serge.hallyn@canonical.com>
      Acked-by: NJan Kara <jack@suse.com>
      Acked-by: NPaul Moore <paul@paul-moore.com>
      Cc: J. R. Okajima <hooanon05g@gmail.com>
      Signed-off-by: NKees Cook <keescook@chromium.org>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a068acf2
  13. 31 7月, 2015 2 次提交
  14. 25 6月, 2015 7 次提交