security/selinux: fix SECURITY_LSM_NATIVE_LABELS on reused superblock
authorJ. Bruce Fields <bfields@redhat.com>
Tue, 5 Mar 2019 21:17:58 +0000 (16:17 -0500)
committerPaul Moore <paul@paul-moore.com>
Mon, 11 Mar 2019 20:13:17 +0000 (16:13 -0400)
commit3815a245b50124f0865415dcb606a034e97494d4
tree9a06379fc9d4b301570e75f209ce5d82e7421153
parent292c997a1970f8d1e1dfa354ed770a22f7b5a434
security/selinux: fix SECURITY_LSM_NATIVE_LABELS on reused superblock

In the case when we're reusing a superblock, selinux_sb_clone_mnt_opts()
fails to set set_kern_flags, with the result that
nfs_clone_sb_security() incorrectly clears NFS_CAP_SECURITY_LABEL.

The result is that if you mount the same NFS filesystem twice, NFS
security labels are turned off, even if they would work fine if you
mounted the filesystem only once.

("fixes" may be not exactly the right tag, it may be more like
"fixed-other-cases-but-missed-this-one".)

Cc: Scott Mayhew <smayhew@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 0b4d3452b8b4 "security/selinux: allow security_sb_clone_mnt_opts..."
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
security/selinux/hooks.c