reiserfs: Protect reiserfs_quota_write() with write lock

Calls into reiserfs journalling code and reiserfs_get_block() need to
be protected with write lock. We remove write lock around calls to high
level quota code in the next patch so these paths would suddently become
unprotected.

CC: stable@vger.kernel.org # >= 3.0
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 4 insertions, 0 deletions

diff --git a/fs/reiserfs/super.c b/fs/reiserfs/super.c
index e59d6ddcc69f..c101704ece48 100644
--- a/fs/reiserfs/super.c
+++ b/fs/reiserfs/super.c
@@ -2338,7 +2338,9 @@ static ssize_t reiserfs_quota_write(struct super_block *sb, int type,
                 tocopy = sb->s_blocksize - offset < towrite ?
                     sb->s_blocksize - offset : towrite;
                 tmp_bh.b_state = 0;
+                reiserfs_write_lock(sb);
                 err = reiserfs_get_block(inode, blk, &tmp_bh, GET_BLOCK_CREATE);
+                reiserfs_write_unlock(sb);
                 if (err)
                         goto out;
                 if (offset || tocopy != sb->s_blocksize)
@@ -2354,10 +2356,12 @@ static ssize_t reiserfs_quota_write(struct super_block *sb, int type,
                 flush_dcache_page(bh->b_page);
                 set_buffer_uptodate(bh);
                 unlock_buffer(bh);
+                reiserfs_write_lock(sb);
                 reiserfs_prepare_for_journal(sb, bh, 1);
                 journal_mark_dirty(current->journal_info, sb, bh);
                 if (!journal_quota)
                         reiserfs_add_ordered_list(inode, bh);
+                reiserfs_write_unlock(sb);
                 brelse(bh);
                 offset = 0;
                 towrite -= tocopy;