lkml.org 
[lkml]   [2010]   [Jun]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    SubjectRe: [PATCH v2] d_ino considered harmful
    On Wed, Jun 16, 2010 at 02:59:13PM -0400, Valerie Aurora wrote:
    > Who needs d_ino anyway? I am running a kernel with this patch -
    > Gnome, a browser, IRC, kernel compile, etc. and everything works.

    Gosh, maybe it would help to patch the currently used readdir instead
    of just old_readdir() (thanks, Arnd). And return 1 instead of 0 so ls
    doesn't think all files are deleted (thanks, Andreas).

    I'm running a kernel with the below patch and everything still works.
    Apparently "ls -i" is still using the bogus d_ino performance
    improvement mentioned here because it returns all 1's for inode
    number.

    http://www.mail-archive.com/bug-findutils@gnu.org/msg02531.html

    -VAL

    commit 5902fd7b7407e059c5cea1bf1ea101a1ff8a6072
    Author: Valerie Aurora <vaurora@redhat.com>
    Date: Wed Jun 16 11:05:06 2010 -0700

    VFS: Always return 1 for d_ino

    Use of d_ino without the corresponding st_dev is always buggy in the
    presence of submounts, bind mounts, and union mounts. E.g., the d_ino
    of a mountpoint will be the inode number of the directory under the
    mountpoint, not the mounted directory. Correct code must call stat(),
    which returns the correct device ID and inode in st_dev and st_ino.
    Since no one should be using d_ino anyway, always return 1 to detect
    bugs.

    diff --git a/fs/readdir.c b/fs/readdir.c
    index dd3eae1..5ff8f10 100644
    --- a/fs/readdir.c
    +++ b/fs/readdir.c
    @@ -91,11 +91,8 @@ static int fillonedir(void * __buf, const char * name, int namlen, loff_t offset

    if (buf->result)
    return -EINVAL;
    - d_ino = ino;
    - if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
    - buf->result = -EOVERFLOW;
    - return -EOVERFLOW;
    - }
    + /* Use of d_ino without st_dev is always buggy. */
    + d_ino = 1;
    buf->result++;
    dirent = buf->dirent;
    if (!access_ok(VERIFY_WRITE, dirent,
    @@ -172,11 +169,8 @@ static int filldir(void * __buf, const char * name, int namlen, loff_t offset,
    buf->error = -EINVAL; /* only used if we fail.. */
    if (reclen > buf->count)
    return -EINVAL;
    - d_ino = ino;
    - if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
    - buf->error = -EOVERFLOW;
    - return -EOVERFLOW;
    - }
    + /* Use of d_ino without st_dev is always buggy. */
    + d_ino = 1;
    dirent = buf->previous;
    if (dirent) {
    if (__put_user(offset, &dirent->d_off))

    \
     
     \ /
      Last update: 2010-06-16 21:57    [W:0.078 / U:60.280 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site