From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1ED5627280A; Mon, 13 Apr 2026 16:16:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776096970; cv=none; b=VOOQv40HfkjTxvDrhRjIGTZ6XE+Sk4r0mxkJlvKlg15UCTcyESr6muUk6VYvEPqXMYH9O0HBTXV6uHWxMZJ1fltv7t0AS/9mnHtO9TdUa5Z28nP2IvB2u8ItozjO6csWMpaWPbSl8sqt/E286BbyJZ0n3zDqKstBgHqFl2O5maM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776096970; c=relaxed/simple; bh=I5Fg248lrxFBShSvssJnNaeUJG8yHAG3lJ9r2h4e/NM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ti4DEp88KvL7xH/deieBBOIjo6SUgNYAB7q6NLKmrHB3FV/QA+xvBA9LLNdQdtUsaCGZC83XcbUjw+5sFKAwDlfcfoCtu/TMvrhR7ycVr0JCkyswPl71iWEpQaLzNyH80AZkYbf3aTqVDUJt8jgrAfBUgbYZNAzdFAViVN80vko= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=HcdltqiE; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="HcdltqiE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A8DADC2BCAF; Mon, 13 Apr 2026 16:16:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1776096970; bh=I5Fg248lrxFBShSvssJnNaeUJG8yHAG3lJ9r2h4e/NM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HcdltqiEihK3Fj402OBpFAkVlXWZEkgy0A2pw8mpSsgQsoWMDwkUmSrnGUEWu26Up qINK/rzZj8evWNoJP0pnnIgzgJm/MHJ8df3JZJpUHwHsvst6Q7B2LBss5pwMZDEm0t xgcn2ayHnPNwQ90+6+ThnGhf4bPI0fHnpkaTOLEA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Qualys Security Advisory , Salvatore Bonaccorso , Georgia Garcia , Cengiz Can , Massimiliano Pellizzer , John Johansen Subject: [PATCH 6.1 12/55] apparmor: validate DFA start states are in bounds in unpack_pdb Date: Mon, 13 Apr 2026 18:00:46 +0200 Message-ID: <20260413155725.287455051@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260413155724.820472494@linuxfoundation.org> References: <20260413155724.820472494@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Massimiliano Pellizzer commit 9063d7e2615f4a7ab321de6b520e23d370e58816 upstream. Backport for conflicts caused by ad596ea74e74 ("apparmor: group dfa policydb unpacking") which rearrange and consolidated the unpack. Start states are read from untrusted data and used as indexes into the DFA state tables. The aa_dfa_next() function call in unpack_pdb() will access dfa->tables[YYTD_ID_BASE][start], and if the start state exceeds the number of states in the DFA, this results in an out-of-bound read. ================================================================== BUG: KASAN: slab-out-of-bounds in aa_dfa_next+0x2a1/0x360 Read of size 4 at addr ffff88811956fb90 by task su/1097 ... Reject policies with out-of-bounds start states during unpacking to prevent the issue. Fixes: ad5ff3db53c6 ("AppArmor: Add ability to load extended policy") Reported-by: Qualys Security Advisory Tested-by: Salvatore Bonaccorso Reviewed-by: Georgia Garcia Reviewed-by: Cengiz Can Signed-off-by: Massimiliano Pellizzer Signed-off-by: John Johansen Signed-off-by: Greg Kroah-Hartman --- security/apparmor/policy_unpack.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-) --- a/security/apparmor/policy_unpack.c +++ b/security/apparmor/policy_unpack.c @@ -824,9 +824,18 @@ static struct aa_profile *unpack_profile error = -EPROTO; goto fail; } - if (!aa_unpack_u32(e, &profile->policy.start[0], "start")) + if (!aa_unpack_u32(e, &profile->policy.start[0], "start")) { /* default start state */ profile->policy.start[0] = DFA_START; + } else { + size_t state_count = profile->policy.dfa->tables[YYTD_ID_BASE]->td_lolen; + + if (profile->policy.start[0] >= state_count) { + info = "invalid dfa start state"; + goto fail; + } + } + /* setup class index */ for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) { profile->policy.start[i] = @@ -847,9 +856,17 @@ static struct aa_profile *unpack_profile info = "failed to unpack profile file rules"; goto fail; } else if (profile->file.dfa) { - if (!aa_unpack_u32(e, &profile->file.start, "dfa_start")) + if (!aa_unpack_u32(e, &profile->file.start, "dfa_start")) { /* default start state */ profile->file.start = DFA_START; + } else { + size_t state_count = profile->file.dfa->tables[YYTD_ID_BASE]->td_lolen; + + if (profile->file.start >= state_count) { + info = "invalid dfa start state"; + goto fail; + } + } } else if (profile->policy.dfa && profile->policy.start[AA_CLASS_FILE]) { profile->file.dfa = aa_get_dfa(profile->policy.dfa);