1. 20 Mar, 2013 38 commits
  2. 06 Mar, 2013 2 commits
    • Ben Hutchings's avatar
      Linux 3.2.40 · 733c7943
      Ben Hutchings authored
      733c7943
    • Theodore Ts'o's avatar
      ext4: fix kernel BUG on large-scale rm -rf commands · 933ef2d5
      Theodore Ts'o authored
      commit 89a4e48f upstream.
      
      Commit 968dee77: "ext4: fix hole punch failure when depth is greater
      than 0" introduced a regression in v3.5.1/v3.6-rc1 which caused kernel
      crashes when users ran run "rm -rf" on large directory hierarchy on
      ext4 filesystems on RAID devices:
      
          BUG: unable to handle kernel NULL pointer dereference at 0000000000000028
      
          Process rm (pid: 18229, threadinfo ffff8801276bc000, task ffff880123631710)
          Call Trace:
           [<ffffffff81236483>] ? __ext4_handle_dirty_metadata+0x83/0x110
           [<ffffffff812353d3>] ext4_ext_truncate+0x193/0x1d0
           [<ffffffff8120a8cf>] ? ext4_mark_inode_dirty+0x7f/0x1f0
           [<ffffffff81207e05>] ext4_truncate+0xf5/0x100
           [<ffffffff8120cd51>] ext4_evict_inode+0x461/0x490
           [<ffffffff811a1312>] evict+0xa2/0x1a0
           [<ffffffff811a1513>] iput+0x103/0x1f0
           [<ffffffff81196d84>] do_unlinkat+0x154/0x1c0
           [<ffffffff8118cc3a>] ? sys_newfstatat+0x2a/0x40
           [<ffffffff81197b0b>] sys_unlinkat+0x1b/0x50
           [<ffffffff816135e9>] system_call_fastpath+0x16/0x1b
          Code: 8b 4d 20 0f b7 41 02 48 8d 04 40 48 8d 04 81 49 89 45 18 0f b7 49 02 48 83 c1 01 49 89 4d 00 e9 ae f8 ff ff 0f 1f 00 49 8b 45 28 <48> 8b 40 28 49 89 45 20 e9 85 f8 ff ff 0f 1f 80 00 00 00
      
          RIP  [<ffffffff81233164>] ext4_ext_remove_space+0xa34/0xdf0
      
      This could be reproduced as follows:
      
      The problem in commit 968dee77 was that caused the variable 'i' to
      be left uninitialized if the truncate required more space than was
      available in the journal.  This resulted in the function
      ext4_ext_truncate_extend_restart() returning -EAGAIN, which caused
      ext4_ext_remove_space() to restart the truncate operation after
      starting a new jbd2 handle.
      Reported-by: default avatarMaciej Żenczykowski <maze@google.com>
      Reported-by: default avatarMarti Raudsepp <marti@juffo.org>
      Tested-by: default avatarFengguang Wu <fengguang.wu@intel.com>
      Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      933ef2d5