Re: [edk2-devel] [PATCH 1/1] NetworkPkg: Fix possible infinite loop in HTTP msg body parser

["Maciej Rabeda" <maciej.rabeda@linux.intel.com>]

Merged.
https://github.com/tianocore/edk2/commit/70c2f10fde5b67b0d7d62ba7ea3271fc514ebcc4
https://github.com/tianocore/edk2/pull/997

On 02-Oct-20 17:08, Vladimir Olovyannikov via groups.io wrote:
> Hi Maciej,
>
> Thank you for reviewing the patch.
>
>> -----Original Message-----
>> From: Rabeda, Maciej <maciej.rabeda@linux.intel.com>
>> Sent: Friday, October 2, 2020 5:02 AM
>> To: Vladimir Olovyannikov <vladimir.olovyannikov@broadcom.com>;
>> devel@edk2.groups.io
>> Cc: Jiaxin Wu <jiaxin.wu@intel.com>; Siyuan Fu <siyuan.fu@intel.com>;
>> Laszlo Ersek <lersek@redhat.com>
>> Subject: Re: [edk2-devel] [PATCH 1/1] NetworkPkg: Fix possible infinite
>> loop
>> in HTTP msg body parser
>>
>> Hi Vladimir,
>>
>> Functionally the patch is fine.
>> However, from coding standard perspective, !PortionLen is not allowed -
>> such structure is used only for BOOLEAN type values.
>> Reference: Table 10,
>> https://edk2-docs.gitbook.io/edk-ii-c-coding-standards-
>> specification/5_source_files/57_c_programming#5-7-2-2-a-comparison-of-
>> any-pointer-to-zero-must-be-done-via-the-null-type
> Sorry, my bad. That's a result of switching between edk2 and Linux
> developments.
>> Do not submit v2, I will correct that upon merging. On terms CS issue is
>> addressed, I am giving:
>> Reviewed-by: Maciej Rabeda <maciej.rabeda@linux.intel.com>
> Thank you Maciej,
>
> Vladimir
>> Thanks,
>> Maciej
>>
>> On 01-Oct-20 17:25, Vladimir Olovyannikov wrote:
>>> Hi Maciej,
>>>
>>> Thank you for looking into this.
>>>
>>> Vladimir
>>>> -----Original Message-----
>>>> From: Rabeda, Maciej <maciej.rabeda@linux.intel.com>
>>>> Sent: Wednesday, September 30, 2020 2:57 AM
>>>> To: devel@edk2.groups.io; vladimir.olovyannikov@broadcom.com
>>>> Cc: Jiaxin Wu <jiaxin.wu@intel.com>; Siyuan Fu <siyuan.fu@intel.com>;
>>>> Laszlo Ersek <lersek@redhat.com>
>>>> Subject: Re: [edk2-devel] [PATCH 1/1] NetworkPkg: Fix possible
>>>> infinite loop in HTTP msg body parser
>>>>
>>>> Hi Vladimir,
>>>>
>>>> Yes, this must have go past my radar, sorry. Things are becoming more
>>>> and more busy out here :/ I will take a look at it by the end of week.
>>>>
>>>> On 24-Sep-20 23:57, Vladimir Olovyannikov via groups.io wrote:
>>>>> Hi Maciej,
>>>>>
>>>>> Can you please review this patch?
>>>>> It is sitting there for a while, looks like it slipped through the
>>>>> cracks.
>>>>>
>>>>> Thank you,
>>>>> Vladimir
>>>>>> -----Original Message-----
>>>>>> From: Vladimir Olovyannikov <vladimir.olovyannikov@broadcom.com>
>>>>>> Sent: Friday, August 28, 2020 11:17 AM
>>>>>> To: devel@edk2.groups.io
>>>>>> Cc: Vladimir Olovyannikov <vladimir.olovyannikov@broadcom.com>;
>>>>>> Maciej Rabeda <maciej.rabeda@linux.intel.com>; Jiaxin Wu
>>>>>> <jiaxin.wu@intel.com>; Siyuan Fu <siyuan.fu@intel.com>
>>>>>> Subject: [PATCH 1/1] NetworkPkg: Fix possible infinite loop in HTTP
>>>>>> msg
>>>>> body
>>>>>> parser
>>>>>>
>>>>>> When an HTTP server sends a non-chunked body data with no
>> Content-
>>>>>> Length header, the HttpParserMessageBody in DxeHttpLib gets
>>>>>> confused and never sets the Char pointer beyond the body start.
>>>>>> This causes "for" loop to never break because the condition of
>>>>>> "Char
>>>>>>> =
>>>>> Body
>>>>>> + BodyLength" is never satisfied.
>>>>>> Use BodyLength as the ContentLength for the parser when
>>>> ContentLength
>>>>>> is absent in HTTP response headers.
>>>>>> BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=2941
>>>>>>
>>>>>> Signed-off-by: Vladimir Olovyannikov
>>>>>> <vladimir.olovyannikov@broadcom.com>
>>>>>> Cc: Maciej Rabeda <maciej.rabeda@linux.intel.com>
>>>>>> Cc: Jiaxin Wu <jiaxin.wu@intel.com>
>>>>>> Cc: Siyuan Fu <siyuan.fu@intel.com>
>>>>>> ---
>>>>>>     NetworkPkg/Library/DxeHttpLib/DxeHttpLib.c | 19
>>>>>> ++++++++++++++++-
>>>> --
>>>>>>     1 file changed, 16 insertions(+), 3 deletions(-)
>>>>>>
>>>>>> diff --git a/NetworkPkg/Library/DxeHttpLib/DxeHttpLib.c
>>>>>> b/NetworkPkg/Library/DxeHttpLib/DxeHttpLib.c
>>>>>> index 180d9321025a..e550c9962dc1 100644
>>>>>> --- a/NetworkPkg/Library/DxeHttpLib/DxeHttpLib.c
>>>>>> +++ b/NetworkPkg/Library/DxeHttpLib/DxeHttpLib.c
>>>>>> @@ -1122,6 +1122,7 @@ HttpParseMessageBody (
>>>>>>       CHAR8                 *Char;
>>>>>>       UINTN                 RemainderLengthInThis;
>>>>>>       UINTN                 LengthForCallback;
>>>>>> +  UINTN                 PortionLength;
>>>>>>       EFI_STATUS            Status;
>>>>>>       HTTP_BODY_PARSER      *Parser;
>>>>>>
>>>>>> @@ -1173,19 +1174,31 @@ HttpParseMessageBody (
>>>>>>           //
>>>>>>           // Identity transfer-coding, just notify user to save the
>>>>>> body
>>>>> data.
>>>>>>           //
>>>>>> +      PortionLength = MIN (
>>>>>> +                        BodyLength,
>>>>>> +                        Parser->ContentLength -
>>>>> Parser->ParsedBodyLength
>>>>>> +                        );
>>>>>> +      if (!PortionLength) {
>>>>>> +        //
>>>>>> +        // Got BodyLength, but no ContentLength. Use BodyLength.
>>>>>> +        //
>>>>>> +        PortionLength = BodyLength;
>>>>>> +        Parser->ContentLength = PortionLength;
>>>>>> +      }
>>>>>> +
>>>>>>           if (Parser->Callback != NULL) {
>>>>>>             Status = Parser->Callback (
>>>>>>                                BodyParseEventOnData,
>>>>>>                                Char,
>>>>>> -                           MIN (BodyLength, Parser->ContentLength -
>>>>> Parser-
>>>>>>> ParsedBodyLength),
>>>>>> +                           PortionLength,
>>>>>>                                Parser->Context
>>>>>>                                );
>>>>>>             if (EFI_ERROR (Status)) {
>>>>>>               return Status;
>>>>>>             }
>>>>>>           }
>>>>>> -      Char += MIN (BodyLength, Parser->ContentLength - Parser-
>>>>>>> ParsedBodyLength);
>>>>>> -      Parser->ParsedBodyLength += MIN (BodyLength, Parser-
>>>>>>> ContentLength - Parser->ParsedBodyLength);
>>>>>> +      Char += PortionLength;
>>>>>> +      Parser->ParsedBodyLength += PortionLength;
>>>>>>           if (Parser->ParsedBodyLength == Parser->ContentLength) {
>>>>>>             Parser->State = BodyParserComplete;
>>>>>>             if (Parser->Callback != NULL) {
>>>>>> --
>>>>>> 2.26.2.266.ge870325ee8
>>>>>
>>>>>
>
> 
>
>