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From:   bfields@fieldses.org
To:     Steve Dickson <steved@redhat.com>
Cc:     linux-nfs@vger.kernel.org,
        Trond Myklebust <trondmy@hammerspace.com>,
        "J. Bruce Fields" <bfields@redhat.com>
Subject: [PATCH 2/2] mountd: never root squash on the pseudofs
Date:   Wed,  2 Dec 2020 20:14:57 -0500
Message-Id: <1606958097-9041-2-git-send-email-bfields@fieldses.org>
In-Reply-To: <1606958097-9041-1-git-send-email-bfields@fieldses.org>
References: <20201203010546.GB348347@pick.fieldses.org>
 <1606958097-9041-1-git-send-email-bfields@fieldses.org>
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From: "J. Bruce Fields" <bfields@redhat.com>

As with security flavors and "secure" ports, we tried to code this so
that pseudofs directories would inherit root squashing from their
children, but it doesn't really work as coded and I'm not sure it's
useful.

Let's just not root squash.  The risk is pretty low since the pseudofs
is readonly, and we'd rather not risk failing a mount unnecessarily.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
---
 utils/mountd/v4root.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/utils/mountd/v4root.c b/utils/mountd/v4root.c
index 39dd87a94e59..c42ba72380ea 100644
--- a/utils/mountd/v4root.c
+++ b/utils/mountd/v4root.c
@@ -34,7 +34,7 @@ static nfs_export pseudo_root = {
 	.m_export = {
 		.e_hostname = "*",
 		.e_path = "/",
-		.e_flags = NFSEXP_READONLY | NFSEXP_ROOTSQUASH
+		.e_flags = NFSEXP_READONLY
 				| NFSEXP_NOSUBTREECHECK | NFSEXP_FSID
 				| NFSEXP_V4ROOT | NFSEXP_INSECURE_PORT,
 		.e_anonuid = 65534,
@@ -60,8 +60,6 @@ set_pseudofs_security(struct exportent *pseudo)
 	struct flav_info *flav;
 	int i;
 
-	if ((flags & NFSEXP_ROOTSQUASH) == 0)
-		pseudo->e_flags &= ~NFSEXP_ROOTSQUASH;
 	for (flav = flav_map; flav < flav_map + flav_map_size; flav++) {
 		struct sec_entry *new;
 
-- 
2.28.0