From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) by lore.proxmox.com (Postfix) with ESMTPS id 731A21FF390 for ; Fri, 24 May 2024 15:22:02 +0200 (CEST) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 685C88B9B; Fri, 24 May 2024 15:22:14 +0200 (CEST) From: Dominik Csapak To: pve-devel@lists.proxmox.com Date: Fri, 24 May 2024 15:21:48 +0200 Message-Id: <20240524132209.703402-5-d.csapak@proxmox.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240524132209.703402-1-d.csapak@proxmox.com> References: <20240524132209.703402-1-d.csapak@proxmox.com> MIME-Version: 1.0 X-SPAM-LEVEL: Spam detection results: 0 AWL 0.016 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Subject: [pve-devel] [PATCH storage v4 04/12] ovf: improve and simplify path checking code X-BeenThere: pve-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox VE development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Proxmox VE development discussion Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: pve-devel-bounces@lists.proxmox.com Sender: "pve-devel" moves the filepath code a bit more closer to where it's actually used checks the contained path before trying to find it's absolute path properly add error handling to realpath instead of checking the combined ovf_path + filepath, just make sure filepath can't point to anythign besides a file in this directory by checking for '.' and '..' (slashes are not allowed in SAFE_CHAR_CLASS_RE) Signed-off-by: Dominik Csapak --- src/PVE/GuestImport/OVF.pm | 36 ++++++++++++++++++------------------ 1 file changed, 18 insertions(+), 18 deletions(-) diff --git a/src/PVE/GuestImport/OVF.pm b/src/PVE/GuestImport/OVF.pm index 0728684..ed1c870 100644 --- a/src/PVE/GuestImport/OVF.pm +++ b/src/PVE/GuestImport/OVF.pm @@ -220,15 +220,6 @@ ovf:Disk[\@ovf:diskId='%s']/\@ovf:capacityAllocationUnits", $disk_id); next; } - # from Disk Node, find corresponding filepath - my $xpath_find_filepath = sprintf("/ovf:Envelope/ovf:References/ovf:File[\@ovf:id='%s']/\@ovf:href", $fileref); - my $filepath = $xpc->findvalue($xpath_find_filepath); - if (!$filepath) { - warn "invalid file reference $fileref, skipping\n"; - next; - } - print "file path: $filepath\n" if $debug; - # from Item, find owning Controller type my $controller_id = $xpc->findvalue('rasd:Parent', $item_node); my $xpath_find_parent_type = sprintf("/ovf:Envelope/ovf:VirtualSystem/ovf:VirtualHardwareSection/\ @@ -244,22 +235,31 @@ ovf:Item[rasd:InstanceID='%s']/rasd:ResourceType", $controller_id); my $adress_on_controller = $xpc->findvalue('rasd:AddressOnParent', $item_node); my $pve_disk_address = id_to_pve($controller_type) . $adress_on_controller; + # from Disk Node, find corresponding filepath + my $xpath_find_filepath = sprintf("/ovf:Envelope/ovf:References/ovf:File[\@ovf:id='%s']/\@ovf:href", $fileref); + my $filepath = $xpc->findvalue($xpath_find_filepath); + if (!$filepath) { + warn "invalid file reference $fileref, skipping\n"; + next; + } + print "file path: $filepath\n" if $debug; + my $original_filepath = $filepath; + ($filepath) = $filepath =~ m|^(${PVE::Storage::SAFE_CHAR_CLASS_RE}+)$|; # untaint & check no sub/parent dirs + die "referenced path '$original_filepath' is invalid\n" if !$filepath || $filepath eq "." || $filepath eq ".."; + # resolve symlinks and relative path components # and die if the diskimage is not somewhere under the $ovf path - my $ovf_dir = realpath(dirname(File::Spec->rel2abs($ovf))); - my $backing_file_path = realpath(join ('/', $ovf_dir, $filepath)); - if ($backing_file_path !~ /^\Q${ovf_dir}\E/) { - die "error parsing $filepath, are you using a symlink ?\n"; - } + my $ovf_dir = realpath(dirname(File::Spec->rel2abs($ovf))) + or die "could not get absolute path of $ovf: $!\n"; + my $backing_file_path = realpath(join ('/', $ovf_dir, $filepath)) + or die "could not get absolute path of $filepath: $!\n"; + + ($backing_file_path) = $backing_file_path =~ m|^(/.*)|; # untaint if (!-e $backing_file_path && !$isOva) { die "error parsing $filepath, file seems not to exist at $backing_file_path\n"; } - ($backing_file_path) = $backing_file_path =~ m|^(/.*)|; # untaint - ($filepath) = $filepath =~ m|^(${PVE::Storage::SAFE_CHAR_CLASS_RE}+)$|; # untaint & check no sub/parent dirs - die "invalid path\n" if !$filepath; - if (!$isOva) { my $size = PVE::Storage::file_size_info($backing_file_path); die "error parsing $backing_file_path, cannot determine file size\n" -- 2.39.2 _______________________________________________ pve-devel mailing list pve-devel@lists.proxmox.com https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel