From 746df9b59c8a5f162c907796c7295d3c4c0d8995 Mon Sep 17 00:00:00 2001 From: David Quigley Date: Wed, 22 May 2013 12:50:35 -0400 Subject: Security: Add Hook to test if the particular xattr is part of a MAC model. The interface to request security labels from user space is the xattr interface. When requesting the security label from an NFS server it is important to make sure the requested xattr actually is a MAC label. This allows us to make sure that we get the desired semantics from the attribute instead of something else such as capabilities or a time based LSM. Acked-by: Eric Paris Acked-by: James Morris Signed-off-by: Matthew N. Dodd Signed-off-by: Miguel Rodel Felipe Signed-off-by: Phua Eu Gene Signed-off-by: Khin Mi Mi Aung Signed-off-by: Trond Myklebust --- security/smack/smack_lsm.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'security/smack/smack_lsm.c') diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index d52c780bdb78..a7f485bb4e2e 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -3328,6 +3328,16 @@ static void smack_audit_rule_free(void *vrule) #endif /* CONFIG_AUDIT */ +/** + * smack_ismaclabel - check if xattr @name references a smack MAC label + * @name: Full xattr name to check. + */ +static int smack_ismaclabel(const char *name) +{ + return (strcmp(name, XATTR_SMACK_SUFFIX) == 0); +} + + /** * smack_secid_to_secctx - return the smack label for a secid * @secid: incoming integer @@ -3524,6 +3534,7 @@ struct security_operations smack_ops = { .audit_rule_free = smack_audit_rule_free, #endif /* CONFIG_AUDIT */ + .ismaclabel = smack_ismaclabel, .secid_to_secctx = smack_secid_to_secctx, .secctx_to_secid = smack_secctx_to_secid, .release_secctx = smack_release_secctx, -- cgit v1.2.3