From 2504db207146543736e877241f3b3de005cbe056 Mon Sep 17 00:00:00 2001
From: John Johansen <john.johansen@canonical.com>
Date: Sat, 26 Mar 2022 01:58:15 -0700
Subject: [PATCH] apparmor: fix overlapping attachment computation
Git-commit: 2504db207146543736e877241f3b3de005cbe056
Patch-mainline: v6.0-rc1
References: git-fixes

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>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 security/apparmor/domain.c         | 2 +-
 security/apparmor/include/policy.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c
index d71023f5c9c4..91689d34d281 100644
--- a/security/apparmor/domain.c
+++ b/security/apparmor/domain.c
@@ -466,7 +466,7 @@ static struct aa_label *find_attach(const struct linux_binprm *bprm,
 				 * 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 cb5ef21991b7..232d3d9566eb 100644
--- 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;
-- 
2.35.3