From: Olga Kornievskaia <okorniev@redhat.com>
Date: Tue, 28 Jan 2025 16:58:06 +0000 (-0500)
Subject: nfsd: fix __fh_verify for localio
X-Git-Tag: v6.14-rc3~45^2~2
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=d9d6b74e4be989f919498798fa40df37a74b5bb0;p=linux-block.git

nfsd: fix __fh_verify for localio

__fh_verify() added a call to svc_xprt_set_valid() to help do connection
management but during LOCALIO path rqstp argument is NULL, leading to
NULL pointer dereferencing and a crash.

Fixes: eccbbc7c00a5 ("nfsd: don't use sv_nrthreads in connection limiting calculations.")
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---

diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c
index bf59f83c6224..91bf0e6d5895 100644
--- a/fs/nfsd/nfsfh.c
+++ b/fs/nfsd/nfsfh.c
@@ -381,8 +381,9 @@ __fh_verify(struct svc_rqst *rqstp,
 	error = check_nfsd_access(exp, rqstp, may_bypass_gss);
 	if (error)
 		goto out;
-
-	svc_xprt_set_valid(rqstp->rq_xprt);
+	/* During LOCALIO call to fh_verify will be called with a NULL rqstp */
+	if (rqstp)
+		svc_xprt_set_valid(rqstp->rq_xprt);
 
 	/* Finally, check access permissions. */
 	error = nfsd_permission(cred, exp, dentry, access);