4.9-stable review patch. If anyone has any objections, please let me know.
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From: Yan, Zheng zyan@redhat.com
commit efe328230dc01aa0b1269aad0b5fae73eea4677a upstream.
This reverts commit 8b8f53af1ed9df88a4c0fbfdf3db58f62060edf3.
splice_dentry() is used by three places. For two places, req->r_dentry is passed to splice_dentry(). In the case of error, req->r_dentry does not get updated. So splice_dentry() should not drop reference.
Cc: stable@vger.kernel.org # 4.18+ Signed-off-by: "Yan, Zheng" zyan@redhat.com Signed-off-by: Ilya Dryomov idryomov@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/ceph/inode.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
--- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -1077,8 +1077,12 @@ static struct dentry *splice_dentry(stru if (IS_ERR(realdn)) { pr_err("splice_dentry error %ld %p inode %p ino %llx.%llx\n", PTR_ERR(realdn), dn, in, ceph_vinop(in)); - dput(dn); - dn = realdn; /* note realdn contains the error */ + dn = realdn; + /* + * Caller should release 'dn' in the case of error. + * If 'req->r_dentry' is passed to this function, + * caller should leave 'req->r_dentry' untouched. + */ goto out; } else if (realdn) { dout("dn %p (%d) spliced with %p (%d) "