Fix ea-in-inode default ACL creation

From: Andreas Gruenbacher (agruen_at_suse.de)
Date: 01/20/05

  • Next message: John Richard Moser: "Re: thoughts on kernel security issues" 
    To: Andrew Morton <akpm@osdl.org>, Linus Torvalds <torvalds@osdl.org>
Date:	Thu, 20 Jan 2005 19:22:25 +0100

    Hello,

    here is another nastiness.

    When a new inode is created, ext3_new_inode sets the EXT3_STATE_NEW
    flag, which tells ext3_do_update_inode to zero out the inode before
    filling in the inode's data. When a file is created in a directory with
    a default acl, the new inode inherits the directory's default acl; this
    generates attributes. The attributes are created before
    ext3_do_update_inode is called to write out the inode. In case of
    in-inode attributes, the new inode's attributes are written, and then
    zeroed out again by ext3_do_update_inode. Bad thing.

    Fix this by recognizing the EXT3_STATE_NEW case in
    ext3_xattr_set_handle, and zeroing out the inode there already when
    necessary.

    Signed-off-by: Andreas Gruenbacher <agruen@suse.de>

    Index: linux-2.6.11-latest/fs/ext3/xattr.c
    ===================================================================
    --- linux-2.6.11-latest.orig/fs/ext3/xattr.c
    +++ linux-2.6.11-latest/fs/ext3/xattr.c
    @@ -954,6 +954,13 @@ ext3_xattr_set_handle(handle_t *handle,
             error = ext3_get_inode_loc(inode, &is.iloc);
             if (error)
                     goto cleanup;
    +
    + if (EXT3_I(inode)->i_state & EXT3_STATE_NEW) {
    + struct ext3_inode *raw_inode = ext3_raw_inode(&is.iloc);
    + memset(raw_inode, 0, EXT3_SB(inode->i_sb)->s_inode_size);
    + EXT3_I(inode)->i_state &= ~EXT3_STATE_NEW;
    + }
    +
             error = ext3_xattr_ibody_find(inode, &i, &is);
             if (error)
                     goto cleanup; 

    -- 
Andreas Gruenbacher <agruen@suse.de>
SUSE Labs, SUSE LINUX GMBH
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