releases/4.9.170/ext4-prohibit-fstrim-in-norecovery-mode.patch

   1 From 92a88a05446bd66749f21ab2afd75e7e17183810 Mon Sep 17 00:00:00 2001
   2 From: "Darrick J. Wong" <darrick.wong@oracle.com>
   3 Date: Sat, 23 Mar 2019 12:10:29 -0400
   4 Subject: ext4: prohibit fstrim in norecovery mode
   5
   6 [ Upstream commit 18915b5873f07e5030e6fb108a050fa7c71c59fb ]
   7
   8 The ext4 fstrim implementation uses the block bitmaps to find free space
   9 that can be discarded.  If we haven't replayed the journal, the bitmaps
  10 will be stale and we absolutely *cannot* use stale metadata to zap the
  11 underlying storage.
  12
  13 Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
  14 Signed-off-by: Theodore Ts'o <tytso@mit.edu>
  15 Signed-off-by: Sasha Levin <sashal@kernel.org>
  16 ---
  17  fs/ext4/ioctl.c | 7 +++++++
  18  1 file changed, 7 insertions(+)
  19
  20 diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
  21 index 2880e017cd0a..2ce73287b53c 100644
  22 --- a/fs/ext4/ioctl.c
  23 +++ b/fs/ext4/ioctl.c
  24 @@ -749,6 +749,13 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
  25                 if (!blk_queue_discard(q))
  26                         return -EOPNOTSUPP;
  27
  28 +               /*
  29 +                * We haven't replayed the journal, so we cannot use our
  30 +                * block-bitmap-guided storage zapping commands.
  31 +                */
  32 +               if (test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb))
  33 +                       return -EROFS;
  34 +
  35                 if (copy_from_user(&range, (struct fstrim_range __user *)arg,
  36                     sizeof(range)))
  37                         return -EFAULT;
  38 --
  39 2.19.1
  40