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 80C291C57B1; Tue, 15 Oct 2024 12:04:06 +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=1728993846; cv=none; b=s5FKzA5I6CpJeOtLidfY03bDXTA5inJqurIH3uwyYOhKTYEkEzuaWdm5v++/9hcOhE889Q/iEZcXWyKP+6De7FVh1b27fEevZmbTDDDeGxJX40ECAvKPPn3/NsD+YxKukEtYn/rDkLATvlpsxFjbicPTU5c49Jd6HlOXDjNGXi0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728993846; c=relaxed/simple; bh=HyslQ8DnO2pedovq8m2dLFCtwwXG3AwbtK6/Lui2vqg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZYH0+sbIhUtn2BvEOjZw22ieyireSHGI58XbuwS3bDa7LwH0s1dH8KmwVWmVcH10y8Do1xYzhCFErkTKKFLOOR8Z+/wlN7ykDNsBRZaOyYZPm9JYW33HGhRhd8UtieZEsy5lr6F0Xq1H5sGSfT2oxUJl35aNFwnLh4Mqe+Lu2uY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=k3YDcC4C; 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="k3YDcC4C" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AA804C4CEC6; Tue, 15 Oct 2024 12:04:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1728993846; bh=HyslQ8DnO2pedovq8m2dLFCtwwXG3AwbtK6/Lui2vqg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=k3YDcC4C0917VCGmyRNzpSzS44D9Y/32Akf/4VHj97UL4i0OFAUQCXuI/ZBNjZayY 5hoEMEMjSn0SV02yQedBN7awmxSp6AV/iDN6GwH5/dKDcwAnlU2OwE4nWe0jZc40Lk gUE28Xk1dSD7RIpsVa1Cwdq04J9fogeEBToERkfQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alfred Agrell , Tetsuo Handa Subject: [PATCH 5.15 534/691] tomoyo: fallback to realpath if symlinks pathname does not exist Date: Tue, 15 Oct 2024 13:28:02 +0200 Message-ID: <20241015112501.535294618@linuxfoundation.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241015112440.309539031@linuxfoundation.org> References: <20241015112440.309539031@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 5.15-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. */