git: 1a27b987f298 - stable/12 - nfscl: Add a missing delegation lock release

From: Rick Macklem <rmacklem_at_FreeBSD.org>
Date: Tue, 09 Nov 2021 23:26:57 UTC
The branch stable/12 has been updated by rmacklem:

URL: https://cgit.FreeBSD.org/src/commit/?id=1a27b987f29806c6b600a61deceb65d30c6049f5

commit 1a27b987f29806c6b600a61deceb65d30c6049f5
Author:     Rick Macklem <rmacklem@FreeBSD.org>
AuthorDate: 2021-10-26 02:09:14 +0000
Commit:     Rick Macklem <rmacklem@FreeBSD.org>
CommitDate: 2021-11-09 23:24:01 +0000

    nfscl: Add a missing delegation lock release
    
    There was a case in nfscl_doiods() where the function would return
    without releasing the delegation shared lock, if it was aquired by
    the call to nfscl_getstateid().  This patch adds that release.
    
    I have never observed a failure due to this missing release, so I
    do not know if it ever happens in practice.  However, since the pNFS
    client is not yet heavily used, it might be the case.
    
    Found by code inspection during a recent NFSv4 IETF working group
    testing event.
    
    (cherry picked from commit 23024f004a4c5659bfcb0b08fac2211ae925ee58)
---
 sys/fs/nfsclient/nfs_clrpcops.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sys/fs/nfsclient/nfs_clrpcops.c b/sys/fs/nfsclient/nfs_clrpcops.c
index 3d26a1dfda88..50f26a5d70c3 100644
--- a/sys/fs/nfsclient/nfs_clrpcops.c
+++ b/sys/fs/nfsclient/nfs_clrpcops.c
@@ -5672,6 +5672,8 @@ nfscl_doiods(vnode_t vp, struct uio *uiop, int *iomode, int *must_commit,
 	if (layp == NULL || rflp == NULL) {
 		if (recalled != 0) {
 			NFSFREECRED(newcred);
+			if (lckp != NULL)
+				nfscl_lockderef(lckp);
 			nfscl_relref(nmp);
 			return (EIO);
 		}