From: Ronnie Sahlberg lsahlber@redhat.com
commit a77592a70081edb58a95b9da18fd5a2882a25666 upstream.
Don't leak a reference to tlink during the NOTIFY ioctl
Signed-off-by: Ronnie Sahlberg lsahlber@redhat.com Signed-off-by: Steve French stfrench@microsoft.com Reviewed-by: Aurelien Aptel aaptel@suse.com CC: Stable stable@vger.kernel.org # v5.6+ Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/cifs/ioctl.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
--- a/fs/cifs/ioctl.c +++ b/fs/cifs/ioctl.c @@ -169,6 +169,7 @@ long cifs_ioctl(struct file *filep, unsi unsigned int xid; struct cifsFileInfo *pSMBFile = filep->private_data; struct cifs_tcon *tcon; + struct tcon_link *tlink; struct cifs_sb_info *cifs_sb; __u64 ExtAttrBits = 0; __u64 caps; @@ -307,13 +308,19 @@ long cifs_ioctl(struct file *filep, unsi break; } cifs_sb = CIFS_SB(inode->i_sb); - tcon = tlink_tcon(cifs_sb_tlink(cifs_sb)); + tlink = cifs_sb_tlink(cifs_sb); + if (IS_ERR(tlink)) { + rc = PTR_ERR(tlink); + break; + } + tcon = tlink_tcon(tlink); if (tcon && tcon->ses->server->ops->notify) { rc = tcon->ses->server->ops->notify(xid, filep, (void __user *)arg); cifs_dbg(FYI, "ioctl notify rc %d\n", rc); } else rc = -EOPNOTSUPP; + cifs_put_tlink(tlink); break; default: cifs_dbg(FYI, "unsupported ioctl\n");