lkml.org 
[lkml]   [2007]   [Jul]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[PATCH] splice: fix bad unlock_page() in error case
    Hi,

    If add_to_page_cache_lru() fails, the page will not be locked. But
    splice jumps to an error path that does a page release and unlock,
    causing a BUG() in unlock_page().

    Fix this by adding one more label that just releases the page. This bug
    was actually triggered on EL5 by gurudas pai <gurudas.pai@oracle.com>
    using fio.

    Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

    diff --git a/fs/splice.c b/fs/splice.c
    index 099b831..4960085 100644
    --- a/fs/splice.c
    +++ b/fs/splice.c
    @@ -628,7 +628,7 @@ find_page:
    ret = add_to_page_cache_lru(page, mapping, index,
    GFP_KERNEL);
    if (unlikely(ret))
    - goto out;
    + goto out_release;
    }

    ret = mapping->a_ops->prepare_write(file, page, offset, offset+this_len);
    @@ -684,8 +684,9 @@ find_page:
    */
    mark_page_accessed(page);
    out:
    - page_cache_release(page);
    unlock_page(page);
    +out_release:
    + page_cache_release(page);
    out_ret:
    return ret;
    }
    --
    Jens Axboe

    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2007-07-20 15:23    [W:0.023 / U:30.812 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site