From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793208123; b=icsRIrIpDLscpYrig6r5ls46/hldAPQTQozGlnvDLBl4B4ma2Jsk+IOwu5FdhKVgo7Ob vKhs0+I7dGFc/2AQc5d9EMgEPF7Y/MRdWFKYqkVcJS18U+AcCtDTG2B8H77Jjfsu+vz2c FllT0AHATeAdAr6JebsxpOBNuMs7SASkIKNi4RwxNeHFqCjUln4ersQWv33G/KEOSXtLd YokUJWa8dFTUGouN3vUHMABxDZUjD5V1PLYdY9RtHF7rlvxVGmA8n3YHDueREsuYNvc8I zb1IlDvWr6FdfEZ+godHlGBuS3WHq6DcDDBxvDEziDkjrjINdowGd418nPaeyQCtLKA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793208123; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=KeykT/ThodXxARSrYgTpVKPGyHjOE+8KzMUU7CyTBFg=; b=IDSTQ/f5AKHRmtfgfBAj8UcbDIh9y/H6iOvKZRCtaBx5V8eQUq+j9Oe3NliDlWNtKugz keCigk0ixiziAFWlCSGTRsN6GP3z7ZpPrW0QVvCDUBc4U0mB6QFea3Nvc8TwCS4ezbpOb bNlz9udotXiCKaddfKa2+esjcChXk0FN9a3QuVHx4G3AMr4VBVa5av9YVpThrFsbXbY66 vh0boA/gBm7DeC04LX4wMPPCRIDi3rgPJTRnR4SZO5qmrnH8fDGZW9s37EfJCeXOSMGJk MOQOxRrJ/FNnjLWiPXj9fJPzLolhjNO8QdDw/Ksn44NxUxeFCnZyHM3cxZrouIVpkMg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=M5+mvh0e; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7C952606A31E; Wed, 28 Oct 2026 17:22:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=M5+mvh0e Received: by smtp.kernel.org (Postfix) with ESMTPSA id CE1B21F031E2; Wed, 28 Oct 2026 17:22:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793208123; bh=KeykT/ThodXxARSrYgTpVKPGyHjOE+8KzMUU7CyTBFg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=M5+mvh0eYDU1gr0t26fiAIHfMR6I0M3ggjRjcwyc0dkVWqBnDDZ+Jl/I9dU+Iyazg oPBr7mAU/2FFHmuArg5Zyn3q0mBG1Xt+JS3xepDyeYVT3uSRqT4F0CNJnuVf++lAZb fEXOmbWFIdTMEG2rpgbHJ1OEUAYJ75yGffhpYxwo= 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 5.10 002/516] apparmor: fix out-of-bounds write when null terminating a label vec Date: Wed, 28 Oct 2026 17:52:34 +0100 Message-ID: <20261028170003.584981324@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170003.522232767@linuxfoundation.org> References: <20261028170003.522232767@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.10-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 55986388dfaeb..a987bd117d88d 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