[PATCH] 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(a)tycho.nsa.gov>
---
selinux/avc.c | 22 +++++++++-------------
1 files changed, 9 insertions(+), 13 deletions(-)
Index: security/selinux/avc.c
===================================================================
--- 6cad4f59214ed4563ddc189bc98f05d1e2b1a5cc/security/selinux/avc.c (mode:100644)
+++ uncommitted/security/selinux/avc.c (mode:100644)
@@ -575,16 +575,16 @@
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 @@
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=(a)%*.*s", len-1,
- len-1, p+1);
+ audit_log_hex(ab, p, len);
break;
}
}
--
Stephen Smalley
National Security Agency