From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 46DF629BDB5; Sat, 17 Oct 2026 16:50:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792255808; cv=none; b=VG/eCq7H6NGvlgK7sWkh7coeJth1Ci9jzin9tV0H7Wp9zGg0VFx7k9i6Uwtd8bxq3P17pT7oMknXqBWKL2fxKeQhuflRYRkWUJf6MIzpTKgfnmVDV2R9nMcdybTXolo9rNVnJSTF39S+J42yDD5hL/N6+nFyp2BCytroFqyYNKs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792255808; c=relaxed/simple; bh=7ekOhjvxEOAAbrUWrGmKvqLTXkEVttYSnsb4ZM3tRe0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=L5mBuSE8eFcW9Ojf5ROqsvvD50F51hqujCHAYD//Wn+KRpNUEKg/l5vZaAlrFBOMLk6N5UbW8Wd1xT992nPx3FklTPWIs66k0hVZoVbmDs7jGr+2UuVW9t2FsNRHCCz8AmbC64Ggs8gi8GI1xXj8fLwnZ+SvrAWpn6/wpVGJJGw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jL3QSgCB; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="jL3QSgCB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 93E9E1F000C4; Sat, 17 Oct 2026 16:50:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792255807; bh=T0+uDMrf2jYl7fRVdtdl6LjZhhaoF8aW+vAWYzJ5vbU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=jL3QSgCB+4HOzIl7P5K+uU9YeUN3Sxog34V9QB78Aidf5SDvc09+dxjwqWuxQ7R64 PmF7tDYiejnx3ehHo6XPqq85Ic+WiIZcktCGzzRnQscSoPZ0KUyON4e7B15rLBT6DH 4YIzGG0T+tKzhYWnFqjhgu3l9zgdSUKlpiUE7bWU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Hyunwoo Kim , John Johansen , Sasha Levin Subject: [PATCH 6.6 0008/1674] apparmor: fix out-of-bounds write when null terminating a label vec Date: Sat, 17 Oct 2026 17:38:00 +0200 Message-ID: <20261017160431.354170314@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261017160431.119607952@linuxfoundation.org> References: <20261017160431.119607952@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hyunwoo Kim [ Upstream commit 9f1e40193eef7f047e6b77cfb4b4cafdecd7a123 ] aa_vec_unique() null terminates at vec[n - dups] when VEC_FLAG_TERMINATE is passed. If the components are all distinct no duplicates are dropped, dups is 0 and the terminator goes to vec[n], so the caller has to provide room for n + 1 entries. aa_label_strn_parse() sets up its vector with vec_setup(profile, vec, len, gfp) and then calls aa_vec_unique(vec, len, VEC_FLAG_TERMINATE), but vec_setup() does not reserve the terminator entry. Up to LOCAL_VEC_ENTRIES it uses the local array of LOCAL_VEC_ENTRIES pointers, above that it allocates exactly len pointers. The terminator therefore lands one entry past the end of the local array when len is LOCAL_VEC_ENTRIES, and one entry past the end of the allocation when len is larger. len comes from the number of "//&" separated components in the label name and label_count_strn_entries() does not bound it. An unprivileged task reaches the parse by writing to /proc/self/attr/apparmor/current or through lsm_set_self_attr(2), both of which go through do_setattr(), and the name is parsed before the change_profile permission is checked. The query_label() path behind the securityfs .access file, which is mode 0666, performs no permission check at all. Every component has to resolve to a loaded profile, so a system with policy loaded is required. The other two VEC_FLAG_TERMINATE users work on a label vec that aa_label_alloc() has already sized with "+ 1 for null terminator entry on vec". Reserve the same entry in vec_setup() and DEFINE_VEC(). Passing len + 1 from the caller instead would move len == LOCAL_VEC_ENTRIES out of the local array and into kzalloc(). Fixes: f1bd904175e8 ("apparmor: add the base fns() for domain labels") Cc: stable@vger.kernel.org Signed-off-by: Hyunwoo Kim Signed-off-by: John Johansen [ replaced unavailable kzalloc_objs() with equivalent kcalloc() allocation ] Signed-off-by: Sasha Levin --- security/apparmor/include/label.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/security/apparmor/include/label.h b/security/apparmor/include/label.h index 5aca0f612f8fd..55b5372ecf240 100644 --- a/security/apparmor/include/label.h +++ b/security/apparmor/include/label.h @@ -22,7 +22,7 @@ struct aa_ns; #define LOCAL_VEC_ENTRIES 8 #define DEFINE_VEC(T, V) \ - struct aa_ ## T *(_ ## V ## _localtmp)[LOCAL_VEC_ENTRIES]; \ + struct aa_ ## T *(_ ## V ## _localtmp)[LOCAL_VEC_ENTRIES + 1]; \ struct aa_ ## T **(V) #define vec_setup(T, V, N, GFP) \ @@ -30,10 +30,10 @@ struct aa_ns; if ((N) <= LOCAL_VEC_ENTRIES) { \ typeof(N) i; \ (V) = (_ ## V ## _localtmp); \ - for (i = 0; i < (N); i++) \ + for (i = 0; i <= (N); i++) \ (V)[i] = NULL; \ } else \ - (V) = kzalloc(sizeof(struct aa_ ## T *) * (N), (GFP)); \ + (V) = kcalloc((N) + 1, sizeof(struct aa_ ## T *), (GFP)); \ (V) ? 0 : -ENOMEM; \ }) -- 2.53.0