[nfs-utils PATCH v2] mountd: don't advertise krb5 for v4root when not configured.
From: NeilBrown <hidden>
Date: 2023-04-18 23:57:58
Subsystem:
the rest · Maintainer:
Linus Torvalds
If /etc/krb5.keytab does not exist, then krb5 cannot work, so
advertising it as an option for v4root is pointless.
Since linux commit 676e4ebd5f2c ("NFSD: SECINFO doesn't handle
unsupported pseudoflavors correctly") this can result in an unhelpful
warning if the krb5 code is not built, or built as a module which is not
installed.
[ 161.668635] NFS: SECINFO: security flavor 390003 is not supported
[ 161.668655] NFS: SECINFO: security flavor 390004 is not supported
[ 161.668670] NFS: SECINFO: security flavor 390005 is not supported
So avoid advertising krb5 security options when krb5.keytab cannot be
found.
Note that testing for /etc/krb5.keytab is what we already do in a couple
of systemd unit file to determine if krb5 is enabled.
Link: https://lore.kernel.org/linux-nfs/20170104190327.v3wbpcbqtfa5jy7d@codemonkey.org.uk/ (local)
Signed-off-by: NeilBrown <redacted>
---
support/export/v4root.c | 2 ++
support/include/pseudoflavors.h | 1 +
support/nfs/exports.c | 14 +++++++-------
3 files changed, 10 insertions(+), 7 deletions(-)
diff --git a/support/export/v4root.c b/support/export/v4root.c
index fbb0ad5f5b81..03805dcb4e6d 100644
--- a/support/export/v4root.c
+++ b/support/export/v4root.c@@ -66,6 +66,8 @@ set_pseudofs_security(struct exportent *pseudo) if (!flav->fnum) continue; + if (flav->need_krb5 && access("/etc/krb5.keytab", F_OK) != 0) + continue; i = secinfo_addflavor(flav, pseudo); new = &pseudo->e_secinfo[i];
diff --git a/support/include/pseudoflavors.h b/support/include/pseudoflavors.h
index deb052b130e6..1f16f3f796f3 100644
--- a/support/include/pseudoflavors.h
+++ b/support/include/pseudoflavors.h@@ -8,6 +8,7 @@ struct flav_info { char *flavour; int fnum; + int need_krb5; }; extern struct flav_info flav_map[];
diff --git a/support/nfs/exports.c b/support/nfs/exports.c
index 2c8f0752ad9d..010dfe423d6f 100644
--- a/support/nfs/exports.c
+++ b/support/nfs/exports.c@@ -36,13 +36,13 @@ (NFSEXP_READONLY|NFSEXP_ROOTSQUASH|NFSEXP_GATHERED_WRITES|NFSEXP_NOSUBTREECHECK) struct flav_info flav_map[] = { - { "krb5", RPC_AUTH_GSS_KRB5 }, - { "krb5i", RPC_AUTH_GSS_KRB5I }, - { "krb5p", RPC_AUTH_GSS_KRB5P }, - { "unix", AUTH_UNIX }, - { "sys", AUTH_SYS }, - { "null", AUTH_NULL }, - { "none", AUTH_NONE }, + { "krb5", RPC_AUTH_GSS_KRB5, 1}, + { "krb5i", RPC_AUTH_GSS_KRB5I, 1}, + { "krb5p", RPC_AUTH_GSS_KRB5P, 1}, + { "unix", AUTH_UNIX, 0}, + { "sys", AUTH_SYS, 0}, + { "null", AUTH_NULL, 0}, + { "none", AUTH_NONE, 0}, }; const int flav_map_size = sizeof(flav_map)/sizeof(flav_map[0]);
--
2.40.0