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    Subject[07/12] JFFS2: Fix free space leak with in-band cleanmarkers
    2.6.24-stable review patch.  If anyone has any objections, please let us
    know.

    ------------------

    From: David Woodhouse <dwmw2@infradead.org>

    We were accounting for the cleanmarker by calling jffs2_link_node_ref()
    (without locking!), which adjusted both superblock and per-eraseblock
    accounting, subtracting the size of the cleanmarker from {jeb,c}->free_size
    and adding it to {jeb,c}->used_size.

    But only _then_ were we adding the size of the newly-erased block back
    to the superblock counts, and we were adding each of jeb->{free,used}_size
    to the corresponding superblock counts. Thus, the size of the cleanmarker
    was effectively subtracted from the superblock's free_size _twice_.

    Fix this, by always adding a full eraseblock size to c->free_size when
    we've erased a block. And call jffs2_link_node_ref() under the proper
    lock, while we're at it.

    Thanks to Alexander Yurchenko and/or Damir Shayhutdinov for (almost)
    pinpointing the problem.

    [Backport of commit 014b164e1392a166fe96e003d2f0e7ad2e2a0bb7]

    Signed-off-by: David Woodhouse <dwmw2@infradead.org>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

    ---
    fs/jffs2/erase.c | 18 ++++++++----------
    1 file changed, 8 insertions(+), 10 deletions(-)

    --- a/fs/jffs2/erase.c
    +++ b/fs/jffs2/erase.c
    @@ -419,9 +419,6 @@ static void jffs2_mark_erased_block(stru
    if (jffs2_write_nand_cleanmarker(c, jeb))
    goto filebad;
    }
    -
    - /* Everything else got zeroed before the erase */
    - jeb->free_size = c->sector_size;
    } else {

    struct kvec vecs[1];
    @@ -449,18 +446,19 @@ static void jffs2_mark_erased_block(stru

    goto filebad;
    }
    -
    - /* Everything else got zeroed before the erase */
    - jeb->free_size = c->sector_size;
    - /* FIXME Special case for cleanmarker in empty block */
    - jffs2_link_node_ref(c, jeb, jeb->offset | REF_NORMAL, c->cleanmarker_size, NULL);
    }
    + /* Everything else got zeroed before the erase */
    + jeb->free_size = c->sector_size;

    down(&c->erase_free_sem);
    spin_lock(&c->erase_completion_lock);
    +
    c->erasing_size -= c->sector_size;
    - c->free_size += jeb->free_size;
    - c->used_size += jeb->used_size;
    + c->free_size += c->sector_size;
    +
    + /* Account for cleanmarker now, if it's in-band */
    + if (c->cleanmarker_size && !jffs2_cleanmarker_oob(c))
    + jffs2_link_node_ref(c, jeb, jeb->offset | REF_NORMAL, c->cleanmarker_size, NULL);

    jffs2_dbg_acct_sanity_check_nolock(c,jeb);
    jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
    --


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