apparmor: fix overlapping attachment computation

commit 2504db207146543736e877241f3b3de005cbe056 upstream.

When finding the profile via patterned attachments, the longest left
match is being set to the static compile time value and not using the
runtime computed value.

Fix this by setting the candidate value to the greater of the
precomputed value or runtime computed value.

Fixes: 21f606610502 ("apparmor: improve overlapping domain attachment resolution")
Signed-off-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c
index f919ebd042fd2571d0fe9707346c71a76c5193cf..87a9e6fd7908d92e9364108b7f563aeaac5cf883 100644 (file)
--- a/security/apparmor/domain.c
+++ b/security/apparmor/domain.c
@@ -465,7 +465,7 @@ restart:
                                 * xattrs, or a longer match
                                 */
                                candidate = profile;
-                               candidate_len = profile->xmatch_len;
+                               candidate_len = max(count, profile->xmatch_len);
                                candidate_xattrs = ret;
                                conflict = false;
                        }

diff --git a/security/apparmor/include/policy.h b/security/apparmor/include/policy.h
index b5b4b8190e654ef77c88d0e752944c08595061db..b5aa4231af682a5412b4641c72ef21d49f769f6c 100644 (file)
--- a/security/apparmor/include/policy.h
+++ b/security/apparmor/include/policy.h
@@ -135,7 +135,7 @@ struct aa_profile {
 
        const char *attach;
        struct aa_dfa *xmatch;
-       int xmatch_len;
+       unsigned int xmatch_len;
        enum audit_mode audit;
        long mode;
        u32 path_flags;