1. 25 9月, 2012 27 次提交
  2. 22 9月, 2012 2 次提交
    • L
      debugfs: fix u32_array race in format_array_alloc · e05e279e
      Linus Torvalds 提交于
      The format_array_alloc() function is fundamentally racy, in that it
      prints the array twice: once to figure out how much space to allocate
      for the buffer, and the second time to actually print out the data.
      
      If any of the array contents changes in between, the allocation size may
      be wrong, and the end result may be truncated in odd ways.
      
      Just don't do it.  Allocate a maximum-sized array up-front, and just
      format the array contents once.  The only user of the u32_array
      interfaces is the Xen spinlock statistics code, and it has 31 entries in
      the arrays, so the maximum size really isn't that big, and the end
      result is much simpler code without the bug.
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e05e279e
    • D
      debugfs: fix race in u32_array_read and allocate array at open · 36048853
      David Rientjes 提交于
      u32_array_open() is racy when multiple threads read from a file with a
      seek position of zero, i.e. when two or more simultaneous reads are
      occurring after the non-seekable files are created.  It is possible that
      file->private_data is double-freed because the threads races between
      
      	kfree(file->private-data);
      
      and
      
      	file->private_data = NULL;
      
      The fix is to only do format_array_alloc() when the file is opened and
      free it when it is closed.
      
      Note that because the file has always been non-seekable, you can't open
      it and read it multiple times anyway, so the data has always been
      generated just once.  The difference is that now it is generated at open
      time rather than at the time of the first read, and that avoids the
      race.
      Reported-by: NDave Jones <davej@redhat.com>
      Acked-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Tested-by: NRaghavendra <raghavendra.kt@linux.vnet.ibm.com>
      Signed-off-by: NDavid Rientjes <rientjes@google.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      36048853
  3. 19 9月, 2012 3 次提交
    • B
      xfs: stop the sync worker before xfs_unmountfs · 0ba6e536
      Ben Myers 提交于
      Cancel work of the xfs_sync_worker before teardown of the log in
      xfs_unmountfs.  This prevents occasional crashes on unmount like so:
      
      PID: 21602  TASK: ee9df060  CPU: 0   COMMAND: "kworker/0:3"
       #0 [c5377d28] crash_kexec at c0292c94
       #1 [c5377d80] oops_end at c07090c2
       #2 [c5377d98] no_context at c06f614e
       #3 [c5377dbc] __bad_area_nosemaphore at c06f6281
       #4 [c5377df4] bad_area_nosemaphore at c06f629b
       #5 [c5377e00] do_page_fault at c070b0cb
       #6 [c5377e7c] error_code (via page_fault) at c070892c
          EAX: f300c6a8  EBX: f300c6a8  ECX: 000000c0  EDX: 000000c0  EBP: c5377ed0
          DS:  007b      ESI: 00000000  ES:  007b      EDI: 00000001  GS:  ffffad20
          CS:  0060      EIP: c0481ad0  ERR: ffffffff  EFLAGS: 00010246
       #7 [c5377eb0] atomic64_read_cx8 at c0481ad0
       #8 [c5377ebc] xlog_assign_tail_lsn_locked at f7cc7c6e [xfs]
       #9 [c5377ed4] xfs_trans_ail_delete_bulk at f7ccd520 [xfs]
      #10 [c5377f0c] xfs_buf_iodone at f7ccb602 [xfs]
      #11 [c5377f24] xfs_buf_do_callbacks at f7cca524 [xfs]
      #12 [c5377f30] xfs_buf_iodone_callbacks at f7cca5da [xfs]
      #13 [c5377f4c] xfs_buf_iodone_work at f7c718d0 [xfs]
      #14 [c5377f58] process_one_work at c024ee4c
      #15 [c5377f98] worker_thread at c024f43d
      #16 [c5377fbc] kthread at c025326b
      #17 [c5377fe8] kernel_thread_helper at c070e834
      
      PID: 26653  TASK: e79143b0  CPU: 3   COMMAND: "umount"
       #0 [cde0fda0] __schedule at c0706595
       #1 [cde0fe28] schedule at c0706b89
       #2 [cde0fe30] schedule_timeout at c0705600
       #3 [cde0fe94] __down_common at c0706098
       #4 [cde0fec8] __down at c0706122
       #5 [cde0fed0] down at c025936f
       #6 [cde0fee0] xfs_buf_lock at f7c7131d [xfs]
       #7 [cde0ff00] xfs_freesb at f7cc2236 [xfs]
       #8 [cde0ff10] xfs_fs_put_super at f7c80f21 [xfs]
       #9 [cde0ff1c] generic_shutdown_super at c0333d7a
      #10 [cde0ff38] kill_block_super at c0333e0f
      #11 [cde0ff48] deactivate_locked_super at c0334218
      #12 [cde0ff58] deactivate_super at c033495d
      #13 [cde0ff68] mntput_no_expire at c034bc13
      #14 [cde0ff7c] sys_umount at c034cc69
      #15 [cde0ffa0] sys_oldumount at c034ccd4
      #16 [cde0ffb0] system_call at c0707e66
      
      commit 11159a05 added this to xfs_log_unmount and needs to be cleaned up
      at a later date.
      Signed-off-by: NBen Myers <bpm@sgi.com>
      Reviewed-by: NDave Chinner <dchinner@redhat.com>
      Reviewed-by: NMark Tinguely <tinguely@sgi.com>
      0ba6e536
    • J
      cifs: fix return value in cifsConvertToUTF16 · c73f6939
      Jeff Layton 提交于
      This function returns the wrong value, which causes the callers to get
      the length of the resulting pathname wrong when it contains non-ASCII
      characters.
      
      This seems to fix https://bugzilla.samba.org/show_bug.cgi?id=6767
      
      Cc: <stable@vger.kernel.org>
      Reported-by: NBaldvin Kovacs <baldvin.kovacs@gmail.com>
      Reported-and-Tested-by: NNicolas Lefebvre <nico.lefebvre@gmail.com>
      Signed-off-by: NJeff Layton <jlayton@redhat.com>
      Signed-off-by: NSteve French <smfrench@gmail.com>
      c73f6939
    • M
      vfs: dcache: use DCACHE_DENTRY_KILLED instead of DCACHE_DISCONNECTED in d_kill() · b161dfa6
      Miklos Szeredi 提交于
      IBM reported a soft lockup after applying the fix for the rename_lock
      deadlock.  Commit c83ce989 ("VFS: Fix the nfs sillyrename regression
      in kernel 2.6.38") was found to be the culprit.
      
      The nfs sillyrename fix used DCACHE_DISCONNECTED to indicate that the
      dentry was killed.  This flag can be set on non-killed dentries too,
      which results in infinite retries when trying to traverse the dentry
      tree.
      
      This patch introduces a separate flag: DCACHE_DENTRY_KILLED, which is
      only set in d_kill() and makes try_to_ascend() test only this flag.
      
      IBM reported successful test results with this patch.
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b161dfa6
  4. 18 9月, 2012 1 次提交
    • F
      fs/proc: fix potential unregister_sysctl_table hang · 6bf61045
      Francesco Ruggeri 提交于
      The unregister_sysctl_table() function hangs if all references to its
      ctl_table_header structure are not dropped.
      
      This can happen sometimes because of a leak in proc_sys_lookup():
      proc_sys_lookup() gets a reference to the table via lookup_entry(), but
      it does not release it when a subsequent call to sysctl_follow_link()
      fails.
      
      This patch fixes this leak by making sure the reference is always
      dropped on return.
      
      See also commit 076c3eed ("sysctl: Rewrite proc_sys_lookup
      introducing find_entry and lookup_entry") which reorganized this code in
      3.4.
      
      Tested in Linux 3.4.4.
      Signed-off-by: NFrancesco Ruggeri <fruggeri@aristanetworks.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      6bf61045
  5. 15 9月, 2012 5 次提交
  6. 13 9月, 2012 2 次提交