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 E39D014AA9; Mon, 14 Oct 2024 15:25:47 +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=1728919548; cv=none; b=d9lMfFhVJQ2miXmg+fnN+F1uJ6fiUSeH5gkwVlDYyqInILT4lkYTFKVJ+CswYcocKZwQfsTaY3+OqBSuoOZ6Mr5yUQdoq+a4LYKWGi6KrOk4X27MYxGPExkCIBR7MbTeUJ0FAv8RGF0cprSVvX1hAIqmHORUg81g26oD16sEWtg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728919548; c=relaxed/simple; bh=J1lZUnJLirdc0alkth/sa1qaqHgtl8x8hchWh5IbPyc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WTlpNb2EDq5l1HaT1TZjYH6w4PgS15icp2AomoiFGClf5OtTpI/tGr5Oh1Q3oMLosv5ZfdfswwpJFufx+yCNOD34epHZ3gCAxhI80MTaNXlGdzNhJBOxzXK8iOwnN96ij9/0a5nQ9C3zNokBorSLzMNtlBoJuU/DA330cshMs7Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=O2bnDZjz; 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="O2bnDZjz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 03747C4CECF; Mon, 14 Oct 2024 15:25:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1728919547; bh=J1lZUnJLirdc0alkth/sa1qaqHgtl8x8hchWh5IbPyc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=O2bnDZjzcba1KjehHFIvYmUBXQG08JxX8Syr6lBdGxA4nBLqL7kMYLNtfyf0dAoBB gFdzctde9wcIWemuY1XOiVfu6QWkDYqaITX6OeS6iIRbN9GYzVM9ryeu1fvUzLKzOX W9B1bnm5JNBLn+4SojXwAOYDKHZxpm5dYdXHGE10= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alfred Agrell , Tetsuo Handa Subject: [PATCH 6.1 596/798] tomoyo: fallback to realpath if symlinks pathname does not exist Date: Mon, 14 Oct 2024 16:19:10 +0200 Message-ID: <20241014141241.418334588@linuxfoundation.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241014141217.941104064@linuxfoundation.org> References: <20241014141217.941104064@linuxfoundation.org> User-Agent: quilt/0.67 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 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tetsuo Handa commit ada1986d07976d60bed5017aa38b7f7cf27883f7 upstream. Alfred Agrell found that TOMOYO cannot handle execveat(AT_EMPTY_PATH) inside chroot environment where /dev and /proc are not mounted, for commit 51f39a1f0cea ("syscalls: implement execveat() system call") missed that TOMOYO tries to canonicalize argv[0] when the filename fed to the executed program as argv[0] is supplied using potentially nonexistent pathname. Since "/dev/fd/" already lost symlink information used for obtaining that , it is too late to reconstruct symlink's pathname. Although part of "/dev/fd//" might not be canonicalized, TOMOYO cannot use tomoyo_realpath_nofollow() when /dev or /proc is not mounted. Therefore, fallback to tomoyo_realpath_from_path() when tomoyo_realpath_nofollow() failed. Reported-by: Alfred Agrell Closes: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1082001 Fixes: 51f39a1f0cea ("syscalls: implement execveat() system call") Cc: stable@vger.kernel.org # v3.19+ Signed-off-by: Tetsuo Handa Signed-off-by: Greg Kroah-Hartman --- security/tomoyo/domain.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) --- a/security/tomoyo/domain.c +++ b/security/tomoyo/domain.c @@ -723,10 +723,13 @@ int tomoyo_find_next_domain(struct linux ee->r.obj = &ee->obj; ee->obj.path1 = bprm->file->f_path; /* Get symlink's pathname of program. */ - retval = -ENOENT; exename.name = tomoyo_realpath_nofollow(original_name); - if (!exename.name) - goto out; + if (!exename.name) { + /* Fallback to realpath if symlink's pathname does not exist. */ + exename.name = tomoyo_realpath_from_path(&bprm->file->f_path); + if (!exename.name) + goto out; + } tomoyo_fill_path_info(&exename); retry: /* Check 'aggregator' directive. */