1. 21 5月, 2012 1 次提交
    • T
      ext4: enable the 64-bit jbd2 feature based on the 64-bit ext4 feature · f32aaf2d
      Theodore Ts'o 提交于
      Previously we were only enabling the 64-bit jbd2 feature if the number
      of blocks in the file system was greater 2**32-1.  The problem with
      this is that it makes it harder to test the 64-bit journal code paths
      with small file systems, since a small test file system would with the
      64-bit ext4 feature enable would use a 64-bit file system on-disk data
      structures, but use a 32-bit journal.
      
      This would also cause problems when trying to do an online resize to
      grow the filesystem above the 2**32-1 boundary.  Fortunately the patch
      to support online resize for 64-bit file systems hasn't been merged
      yet, so this problem hasn't arisen in practice.
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      f32aaf2d
  2. 30 4月, 2012 4 次提交
  3. 24 4月, 2012 1 次提交
  4. 17 4月, 2012 2 次提交
  5. 22 3月, 2012 2 次提交
  6. 21 3月, 2012 2 次提交
  7. 20 3月, 2012 2 次提交
  8. 05 3月, 2012 4 次提交
  9. 04 3月, 2012 4 次提交
  10. 03 3月, 2012 2 次提交
  11. 02 3月, 2012 1 次提交
  12. 21 2月, 2012 3 次提交
  13. 11 1月, 2012 1 次提交
    • X
      ext4: fix undefined behavior in ext4_fill_flex_info() · d50f2ab6
      Xi Wang 提交于
      Commit 503358ae ("ext4: avoid divide by
      zero when trying to mount a corrupted file system") fixes CVE-2009-4307
      by performing a sanity check on s_log_groups_per_flex, since it can be
      set to a bogus value by an attacker.
      
      	sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
      	groups_per_flex = 1 << sbi->s_log_groups_per_flex;
      
      	if (groups_per_flex < 2) { ... }
      
      This patch fixes two potential issues in the previous commit.
      
      1) The sanity check might only work on architectures like PowerPC.
      On x86, 5 bits are used for the shifting amount.  That means, given a
      large s_log_groups_per_flex value like 36, groups_per_flex = 1 << 36
      is essentially 1 << 4 = 16, rather than 0.  This will bypass the check,
      leaving s_log_groups_per_flex and groups_per_flex inconsistent.
      
      2) The sanity check relies on undefined behavior, i.e., oversized shift.
      A standard-confirming C compiler could rewrite the check in unexpected
      ways.  Consider the following equivalent form, assuming groups_per_flex
      is unsigned for simplicity.
      
      	groups_per_flex = 1 << sbi->s_log_groups_per_flex;
      	if (groups_per_flex == 0 || groups_per_flex == 1) {
      
      We compile the code snippet using Clang 3.0 and GCC 4.6.  Clang will
      completely optimize away the check groups_per_flex == 0, leaving the
      patched code as vulnerable as the original.  GCC keeps the check, but
      there is no guarantee that future versions will do the same.
      Signed-off-by: NXi Wang <xi.wang@gmail.com>
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      Cc: stable@vger.kernel.org
      d50f2ab6
  14. 10 1月, 2012 1 次提交
  15. 07 1月, 2012 2 次提交
  16. 05 1月, 2012 1 次提交
  17. 04 1月, 2012 1 次提交
    • A
      vfs: fix the stupidity with i_dentry in inode destructors · 6b520e05
      Al Viro 提交于
      Seeing that just about every destructor got that INIT_LIST_HEAD() copied into
      it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once();
      the cost of taking it into inode_init_always() will be negligible for pipes
      and sockets and negative for everything else.  Not to mention the removal of
      boilerplate code from ->destroy_inode() instances...
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      6b520e05
  18. 19 12月, 2011 1 次提交
  19. 13 12月, 2011 1 次提交
  20. 22 11月, 2011 1 次提交
    • T
      freezer: unexport refrigerator() and update try_to_freeze() slightly · a0acae0e
      Tejun Heo 提交于
      There is no reason to export two functions for entering the
      refrigerator.  Calling refrigerator() instead of try_to_freeze()
      doesn't save anything noticeable or removes any race condition.
      
      * Rename refrigerator() to __refrigerator() and make it return bool
        indicating whether it scheduled out for freezing.
      
      * Update try_to_freeze() to return bool and relay the return value of
        __refrigerator() if freezing().
      
      * Convert all refrigerator() users to try_to_freeze().
      
      * Update documentation accordingly.
      
      * While at it, add might_sleep() to try_to_freeze().
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Cc: Samuel Ortiz <samuel@sortiz.org>
      Cc: Chris Mason <chris.mason@oracle.com>
      Cc: "Theodore Ts'o" <tytso@mit.edu>
      Cc: Steven Whitehouse <swhiteho@redhat.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Jan Kara <jack@suse.cz>
      Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
      Cc: Christoph Hellwig <hch@infradead.org>
      a0acae0e
  21. 07 11月, 2011 2 次提交
  22. 27 10月, 2011 1 次提交
    • E
      ext4: optimize ext4_ext_convert_to_initialized() · 6f91bc5f
      Eric Gouriou 提交于
      This patch introduces a fast path in ext4_ext_convert_to_initialized()
      for the case when the conversion can be performed by transferring
      the newly initialized blocks from the uninitialized extent into
      an adjacent initialized extent. Doing so removes the expensive
      invocations of memmove() which occur during extent insertion and
      the subsequent merge.
      
      In practice this should be the common case for clients performing
      append writes into files pre-allocated via
      fallocate(FALLOC_FL_KEEP_SIZE). In such a workload performed via
      direct IO and when using a suboptimal implementation of memmove()
      (x86_64 prior to the 2.6.39 rewrite), this patch reduces kernel CPU
      consumption by 32%.
      
      Two new trace points are added to ext4_ext_convert_to_initialized()
      to offer visibility into its operations. No exit trace point has
      been added due to the multiplicity of return points. This can be
      revisited once the upstream cleanup is backported.
      Signed-off-by: NEric Gouriou <egouriou@google.com>
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      6f91bc5f