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 718561B219E; Tue, 15 Oct 2024 13:18:07 +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=1728998287; cv=none; b=rQrnO5uSBVTlYE3g1ULs9ZrxkmYfoE4MUPfpfDO1KkTVphADlO98mOzU1IprNR4GM/pvdYYrv9SQpkMptgipClHsG2w/TGVxEm1oJkzBhKVdIl4shicX3KO4/WlX5kNvivFySmR2dqAMfiuruhSG2QiSN6P9HRDAk69M95UX85g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728998287; c=relaxed/simple; bh=OSifmnwtauMn0OYTo25xstDzu2DCeMpdnpzowxeqr5Y=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Mt9oT0vT/nd3q1yxhJrUDgXcKE3FcDjY9uv/4lqplZR0FELpG1iHB6F4bU+n24gRGkSloHXK5TJp99abfBHzBg5UfKjZPoEHjqnCJ1nR+inTvSR+9ZrPOAKjYwOqcE2S8eBKOUl1fbe3zvK/G6g+X1vlw7ctCPgtl53pzLWnyio= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=W6yURwuj; 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="W6yURwuj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D6AEAC4CEC6; Tue, 15 Oct 2024 13:18:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1728998287; bh=OSifmnwtauMn0OYTo25xstDzu2DCeMpdnpzowxeqr5Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=W6yURwuj0iYbvSYcVZWzjLVON27Wyl7ztsbSEU+jnCD2zzx5bAte7j9u4KIP77xvE Ul8qOi3A1Fp4OxZxBDD0yi7S0EdIbp+EkB/2+VOXZALkQq4X1GGArbobotdTFHSTgu EkgKzDirNojWTW3m+ypPAOWLrk5E9UD8K0XFxli8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alfred Agrell , Tetsuo Handa Subject: [PATCH 5.10 406/518] tomoyo: fallback to realpath if symlinks pathname does not exist Date: Tue, 15 Oct 2024 14:45:10 +0200 Message-ID: <20241015123932.651987107@linuxfoundation.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241015123916.821186887@linuxfoundation.org> References: <20241015123916.821186887@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 5.10-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 @@ -725,10 +725,13 @@ 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. */