git: 3e230e0cc4ad - main - nfsd: Fix handling of the error case for nfsvno_open some more

From: Rick Macklem <rmacklem_at_FreeBSD.org>
Date: Sat, 11 Feb 2023 03:36:00 UTC
The branch main has been updated by rmacklem:

URL: https://cgit.FreeBSD.org/src/commit/?id=3e230e0cc4ad822554afaaa07369ca5ccb62054d

commit 3e230e0cc4ad822554afaaa07369ca5ccb62054d
Author:     Rick Macklem <rmacklem@FreeBSD.org>
AuthorDate: 2023-02-11 03:34:57 +0000
Commit:     Rick Macklem <rmacklem@FreeBSD.org>
CommitDate: 2023-02-11 03:34:57 +0000

    nfsd: Fix handling of the error case for nfsvno_open some more
    
    Commit ded5f2954e1a defined done_namei to indicate that
    nd_repstat was set after a successful nfsvno_namei(),
    so that a cleanup needs to be done in nfsvno_open().
    However, it missed the case where a call to
    nfsrv_opencheck() in nfsvno_open() sets nd_repstat non-zero.
    
    This would cause panics due to a dangling locked vnode
    when nfsrv_opencheck() set nd_repstat, such as during grace
    just after a server boot.
    
    This patch fixes the problem.
    
    PR:     268971
---
 sys/fs/nfsserver/nfs_nfsdport.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/sys/fs/nfsserver/nfs_nfsdport.c b/sys/fs/nfsserver/nfs_nfsdport.c
index 7305ae6a84fe..daa57222fe22 100644
--- a/sys/fs/nfsserver/nfs_nfsdport.c
+++ b/sys/fs/nfsserver/nfs_nfsdport.c
@@ -1842,10 +1842,19 @@ nfsvno_open(struct nfsrv_descript *nd, struct nameidata *ndp,
 	u_quad_t tempsize;
 	struct nfsexstuff nes;
 	struct thread *p = curthread;
+	uint32_t oldrepstat;
 
-	if (ndp->ni_vp == NULL)
+	if (ndp->ni_vp == NULL) {
+		/*
+		 * If nfsrv_opencheck() sets nd_repstat, done_namei needs to be
+		 * set true, since cleanup after nfsvno_namei() is needed.
+		 */
+		oldrepstat = nd->nd_repstat;
 		nd->nd_repstat = nfsrv_opencheck(clientid,
 		    stateidp, stp, NULL, nd, p, nd->nd_repstat);
+		if (nd->nd_repstat != 0 && oldrepstat == 0)
+			done_namei = true;
+	}
 	if (!nd->nd_repstat) {
 		if (ndp->ni_vp == NULL) {
 			nd->nd_repstat = VOP_CREATE(ndp->ni_dvp,