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@xxxxxxxxxx>
Reviewed-and-Tested-by: Suresh Jayaraman <sjayaraman@xxxxxxx>
---
fs/cifs/readdir.c | 29 ++++++++++++++++-------------
1 files changed, 16 insertions(+), 13 deletions(-)
diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
index c8961c5..fd0db58 100644
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -227,26 +227,29 @@ 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) {
--
1.7.2.3
--
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