path: root/security/security.c
diff options
authorScott Mayhew <smayhew@redhat.com>2017-06-05 11:45:04 -0400
committerPaul Moore <paul@paul-moore.com>2017-06-09 16:17:47 -0400
commit0b4d3452b8b4a5309b4445b900e3cec022cca95a (patch)
tree3c758827bc8bab1cd36f9c551840cdae00636e97 /security/security.c
parentselinux: use kmem_cache for ebitmap (diff)
security/selinux: allow security_sb_clone_mnt_opts to enable/disable native labeling behavior
When an NFSv4 client performs a mount operation, it first mounts the NFSv4 root and then does path walk to the exported path and performs a submount on that, cloning the security mount options from the root's superblock to the submount's superblock in the process. Unless the NFS server has an explicit fsid=0 export with the "security_label" option, the NFSv4 root superblock will not have SBLABEL_MNT set, and neither will the submount superblock after cloning the security mount options. As a result, setxattr's of security labels over NFSv4.2 will fail. In a similar fashion, NFSv4.2 mounts mounted with the context= mount option will not show the correct labels because the nfs_server->caps flags of the cloned superblock will still have NFS_CAP_SECURITY_LABEL set. Allowing the NFSv4 client to enable or disable SECURITY_LSM_NATIVE_LABELS behavior will ensure that the SBLABEL_MNT flag has the correct value when the client traverses from an exported path without the "security_label" option to one with the "security_label" option and vice versa. Similarly, checking to see if SECURITY_LSM_NATIVE_LABELS is set upon return from security_sb_clone_mnt_opts() and clearing NFS_CAP_SECURITY_LABEL if necessary will allow the correct labels to be displayed for NFSv4.2 mounts mounted with the context= mount option. Resolves: https://github.com/SELinuxProject/selinux-kernel/issues/35 Signed-off-by: Scott Mayhew <smayhew@redhat.com> Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov> Tested-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Paul Moore <paul@paul-moore.com>
Diffstat (limited to 'security/security.c')
1 files changed, 5 insertions, 2 deletions
diff --git a/security/security.c b/security/security.c
index 714433e3e9a2..30132378d103 100644
--- a/security/security.c
+++ b/security/security.c
@@ -420,9 +420,12 @@ int security_sb_set_mnt_opts(struct super_block *sb,
int security_sb_clone_mnt_opts(const struct super_block *oldsb,
- struct super_block *newsb)
+ struct super_block *newsb,
+ unsigned long kern_flags,
+ unsigned long *set_kern_flags)
- return call_int_hook(sb_clone_mnt_opts, 0, oldsb, newsb);
+ return call_int_hook(sb_clone_mnt_opts, 0, oldsb, newsb,
+ kern_flags, set_kern_flags);