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 a29e69d2c30057af24c0e10a64c676841564075e..97721115340fc9fb846788b3eba27be59aa60e13 100644 (file)
--- a/security/apparmor/domain.c
+++ b/security/apparmor/domain.c
@@ -466,7 +466,7 @@ 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 cb5ef21991b72cc46b288d7680f77b6c705d3ab5..232d3d9566eb7f798430eb641d08b7135190d228 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;