AUDIT: Fix remaining cases of direct logging of untrusted strings by avc_audit

Per Steve Grubb's observation that there are some remaining cases where
avc_audit() directly logs untrusted strings without escaping them, here
is a patch that changes avc_audit() to use audit_log_untrustedstring()
or audit_log_hex() as appropriate.  Note that d_name.name is nul-
terminated by d_alloc(), and that sun_path is nul-terminated by
unix_mkname(), so it is not necessary for the AVC to create nul-
terminated copies or to alter audit_log_untrustedstring to take a length
argument.  In the case of an abstract name, we use audit_log_hex() with
an explicit length.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

diff --git a/security/selinux/avc.c b/security/selinux/avc.c
index 914d0d2..4515024 100644 (file)
--- a/security/selinux/avc.c
+++ b/security/selinux/avc.c
@@ -575,16 +575,16 @@ void avc_audit(u32 ssid, u32 tsid,
                                struct dentry *dentry = a->u.fs.dentry;
                                if (a->u.fs.mnt)
                                        audit_avc_path(dentry, a->u.fs.mnt);
-                               audit_log_format(ab, " name=%s",
-                                                dentry->d_name.name);
+                               audit_log_format(ab, " name=");
+                               audit_log_untrustedstring(ab, dentry->d_name.name);
                                inode = dentry->d_inode;
                        } else if (a->u.fs.inode) {
                                struct dentry *dentry;
                                inode = a->u.fs.inode;
                                dentry = d_find_alias(inode);
                                if (dentry) {
-                                       audit_log_format(ab, " name=%s",
-                                                        dentry->d_name.name);
+                                       audit_log_format(ab, " name=");
+                                       audit_log_untrustedstring(ab, dentry->d_name.name);
                                        dput(dentry);
                                }
                        }
@@ -628,23 +628,19 @@ void avc_audit(u32 ssid, u32 tsid,
                                        u = unix_sk(sk);
                                        if (u->dentry) {
                                                audit_avc_path(u->dentry, u->mnt);
-                                               audit_log_format(ab, " name=%s",
-                                                                u->dentry->d_name.name);
-
+                                               audit_log_format(ab, " name=");
+                                               audit_log_untrustedstring(ab, u->dentry->d_name.name);
                                                break;
                                        }
                                        if (!u->addr)
                                                break;
                                        len = u->addr->len-sizeof(short);
                                        p = &u->addr->name->sun_path[0];
+                                       audit_log_format(ab, " path=");
                                        if (*p)
-                                               audit_log_format(ab,
-                                                       "path=%*.*s", len,
-                                                       len, p);
+                                               audit_log_untrustedstring(ab, p);
                                        else
-                                               audit_log_format(ab,
-                                                       "path=@%*.*s", len-1,
-                                                       len-1, p+1);
+                                               audit_log_hex(ab, p, len);
                                        break;
                                }
                        }