cifs: don't take extra tlink reference in initiate_cifs_search

It's possible for initiate_cifs_search to be called on a filp that
already has private_data attached. If this happens, we'll end up
calling cifs_sb_tlink, taking an extra reference to the tlink and
attaching that to the cifsFileInfo. This leads to refcount leaks
that manifest as a "stuck" cifsd at umount time.

Fix this by only looking up the tlink for the cifsFile on the filp's
first pass through this function. When called on a filp that already
has cifsFileInfo associated with it, just use the tlink reference
that it already owns.

This patch fixes samba.org bug 7792:

    https://bugzilla.samba.org/show_bug.cgi?id=7792

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-and-Tested-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
This commit is contained in:
Jeff Layton 2010-11-12 06:30:29 -05:00 committed by Steve French
parent 987b21d7d9
commit 59c55ba1fb

View File

@ -226,26 +226,29 @@ static int initiate_cifs_search(const int xid, struct file *file)
char *full_path = NULL;
struct cifsFileInfo *cifsFile;
struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
struct tcon_link *tlink;
struct tcon_link *tlink = NULL;
struct cifsTconInfo *pTcon;
tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink))
return PTR_ERR(tlink);
pTcon = tlink_tcon(tlink);
if (file->private_data == NULL)
file->private_data =
kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
if (file->private_data == NULL) {
rc = -ENOMEM;
goto error_exit;
tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink))
return PTR_ERR(tlink);
cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
if (cifsFile == NULL) {
rc = -ENOMEM;
goto error_exit;
}
file->private_data = cifsFile;
cifsFile->tlink = cifs_get_tlink(tlink);
pTcon = tlink_tcon(tlink);
} else {
cifsFile = file->private_data;
pTcon = tlink_tcon(cifsFile->tlink);
}
cifsFile = file->private_data;
cifsFile->invalidHandle = true;
cifsFile->srch_inf.endOfSearch = false;
cifsFile->tlink = cifs_get_tlink(tlink);
full_path = build_path_from_dentry(file->f_path.dentry);
if (full_path == NULL) {