From: Xiyu Yang Date: Sat, 13 Jun 2020 12:27:09 +0000 (+0800) Subject: cifs: Fix cached_fid refcnt leak in open_shroot X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=77577de64167aa0643d47ffbaacf3642632b321b;p=linux.git cifs: Fix cached_fid refcnt leak in open_shroot open_shroot() invokes kref_get(), which increases the refcount of the "tcon->crfid" object. When open_shroot() returns not zero, it means the open operation failed and close_shroot() will not be called to decrement the refcount of the "tcon->crfid". The reference counting issue happens in one normal path of open_shroot(). When the cached root have been opened successfully in a concurrent process, the function increases the refcount and jump to "oshr_free" to return. However the current return value "rc" may not equal to 0, thus the increased refcount will not be balanced outside the function, causing a refcnt leak. Fix this issue by setting the value of "rc" to 0 before jumping to "oshr_free" label. Signed-off-by: Xiyu Yang Signed-off-by: Xin Tan Signed-off-by: Steve French CC: Stable --- diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 736d86b8a910b..28553d45604e8 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -763,6 +763,7 @@ int open_shroot(unsigned int xid, struct cifs_tcon *tcon, /* close extra handle outside of crit sec */ SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid); } + rc = 0; goto oshr_free; }