Re: [libapreq2] nits to pick about the patches to util.c over the past few years

[Joe Schaefer]

Forgive me for summarizing, but I didn’t come here expecting help, much
less collaboration on a solution.  I came here expecting to be scolded for
having the temerity to critique the quality of the patch sets you’ve been
shipping of late In libapreq2.  None of my opinions have changed on that
subject, and won’t for some time.

The point is I’m part of your extended support channels for libapreq2,
because it’s easy and fun to help people who use the code.  I’m not here to
complain, I’m here expecting more empathy for people like me who give their
time graciously without expecting anything in return other than some
measure of respect for the effort involved.

On Sat, Oct 29, 2022 at 9:59 PM Joe Schaefer  wrote:

> Missed one.  The patch that introduced these changes was revision=1895107.
>
>
>
> On Sat, Oct 29, 2022 at 9:15 PM Joe Schaefer  wrote:
>
>> Of course, I don’t know how to advise you regarding the security aspects,
>> since you’re doing what you thought was the right thing to do and put the
>> mfd parser into an error state instead of leaving well enough alone.  But
>> basically libapreq2 users get annoyed when the parser breaks on valid
>> input, and may get antsy when their server goes bonkers because they aren’t
>> in the habit of doing error handling on this condition.
>>
>> On Sat, Oct 29, 2022 at 8:36 PM Joe Schaefer  wrote:
>>
>>> Found the problem: it's just a misunderstanding about what is admissible
>>> in a successful file upload widget.
>>> If someone doesn't add a file to the upload widget, it is still a
>>> successful control and should be processed as such on the server.
>>> In this case, just like with opera, the filename attribute will be
>>> present, but set to an empty double-quoted string.
>>>
>>> Here's my patchset, enjoy.
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> On Sat, Oct 29, 2022 at 2:47 PM Joe Schaefer  wrote:
>>>
 Curiously, this doesn't seem to present any problems for
 apreq_header_attribute in trunk/HEAD.  A good thing.

 That means we may need to look more closely at r1903484 in glue/perl.

 On Sat, Oct 29, 2022 at 2:12 PM Joe Schaefer 
 wrote:

>
> On Sat, Oct 29, 2022 at 1:16 PM Joe Schaefer 
> wrote:
>
>>
>>
>> On Sat, Oct 29, 2022 at 1:00 PM Yann Ylavic 
>> wrote:
>>
>>> Hi Joe,
>>>
>>> here comes the "goofer".
>>>
>>> On Fri, Oct 28, 2022 at 9:05 PM  wrote:
>>> >
>>> > Long time fan, not a first time caller.
>>>
>>> Yet what a crappy thread (and comments on [1]).
>>> All top posting, unreplyable.
>>>
>>> >
>>> > Libapreq2 was intended to be a safe,fast, standards compliant
>>> library- primarily *safe* before all other priorities.  Some of the work
>>> going on lately in util.c is starting to undermine that prime 
>>> directive, so
>>> I’d like to better understand why these changes are happening, and why 
>>> they
>>> are snowballing into a less functional, less secure software product 
>>> that
>>> is driving up my support costs on CPAN.
>>>
>>> Yeah sure, rewriting history. That marvelous previous 2.16 just
>>> exploded when faced with google's oss-fuzzers (and not just a little,
>>> quite some reports) which now fuzz httpd trunk (thus apreq).
>>> CVE-2022-22728 is about libapreq2 v2.16 *and earlier" right? So
>>> something pre-dated my changes.
>>
>>
>> Fair enough.
>>
>>
>>>
>> >
>>> > For instance, this revision 1867789 is a pure pessimization:  it
>>> trades userland RAM for filesystem cache RAM, that’s it, but it’s not a 
>>> big
>>> deal.  Just churn.
>>>
>>> I call it a fix for an UAF (Use After Free). This is my only change
>>> in
>>> 2.16 btw, while you seem to suggest that security issues started with
>>> 2.16.
>>>
>>> >
>>> > Everything in the crufty, old apreq_header_attribute code I wrote
>>> was completely tossed and reimplemented.  Why?
>>>
>>> Someone had to address the security reports, and someone (me) dared
>>> touching your code because it was not safe (i.e.
>>> broken/crashing/vulnerable/..), not for the lulz nor breaking users.
>>> I'm very sorry if that happened, only those who do nothing do not
>>> break anything though.
>>> Existing tests were still passing, but shit happens.
>>>
>>
>> Then lets deal with it by adding more tests.
>>
>>
>>>
>>> >  We’re just racking up CVE’s, people are disabling the mfd parser
>>> altogether, and it no longer support common use cases that people now
>>> complain about because it supported cases in the wild that the new work
>>> does not.
>>>
>>> Are there multiple issues? I know of the one reported in [1] about
>>> "file upload does not work if any file fields are blank".
>>> That's not actionable sorry (I don't understand what it means), no
>>> more than your rant 

Re: [libapreq2] nits to pick about the patches to util.c over the past few years

[Joe Schaefer]

Missed one.  The patch that introduced these changes was revision=1895107.



On Sat, Oct 29, 2022 at 9:15 PM Joe Schaefer  wrote:

> Of course, I don’t know how to advise you regarding the security aspects,
> since you’re doing what you thought was the right thing to do and put the
> mfd parser into an error state instead of leaving well enough alone.  But
> basically libapreq2 users get annoyed when the parser breaks on valid
> input, and may get antsy when their server goes bonkers because they aren’t
> in the habit of doing error handling on this condition.
>
> On Sat, Oct 29, 2022 at 8:36 PM Joe Schaefer  wrote:
>
>> Found the problem: it's just a misunderstanding about what is admissible
>> in a successful file upload widget.
>> If someone doesn't add a file to the upload widget, it is still a
>> successful control and should be processed as such on the server.
>> In this case, just like with opera, the filename attribute will be
>> present, but set to an empty double-quoted string.
>>
>> Here's my patchset, enjoy.
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> On Sat, Oct 29, 2022 at 2:47 PM Joe Schaefer  wrote:
>>
>>> Curiously, this doesn't seem to present any problems for
>>> apreq_header_attribute in trunk/HEAD.  A good thing.
>>>
>>> That means we may need to look more closely at r1903484 in glue/perl.
>>>
>>> On Sat, Oct 29, 2022 at 2:12 PM Joe Schaefer  wrote:
>>>

 On Sat, Oct 29, 2022 at 1:16 PM Joe Schaefer 
 wrote:

>
>
> On Sat, Oct 29, 2022 at 1:00 PM Yann Ylavic 
> wrote:
>
>> Hi Joe,
>>
>> here comes the "goofer".
>>
>> On Fri, Oct 28, 2022 at 9:05 PM  wrote:
>> >
>> > Long time fan, not a first time caller.
>>
>> Yet what a crappy thread (and comments on [1]).
>> All top posting, unreplyable.
>>
>> >
>> > Libapreq2 was intended to be a safe,fast, standards compliant
>> library- primarily *safe* before all other priorities.  Some of the work
>> going on lately in util.c is starting to undermine that prime directive, 
>> so
>> I’d like to better understand why these changes are happening, and why 
>> they
>> are snowballing into a less functional, less secure software product that
>> is driving up my support costs on CPAN.
>>
>> Yeah sure, rewriting history. That marvelous previous 2.16 just
>> exploded when faced with google's oss-fuzzers (and not just a little,
>> quite some reports) which now fuzz httpd trunk (thus apreq).
>> CVE-2022-22728 is about libapreq2 v2.16 *and earlier" right? So
>> something pre-dated my changes.
>
>
> Fair enough.
>
>
>>
> >
>> > For instance, this revision 1867789 is a pure pessimization:  it
>> trades userland RAM for filesystem cache RAM, that’s it, but it’s not a 
>> big
>> deal.  Just churn.
>>
>> I call it a fix for an UAF (Use After Free). This is my only change in
>> 2.16 btw, while you seem to suggest that security issues started with
>> 2.16.
>>
>> >
>> > Everything in the crufty, old apreq_header_attribute code I wrote
>> was completely tossed and reimplemented.  Why?
>>
>> Someone had to address the security reports, and someone (me) dared
>> touching your code because it was not safe (i.e.
>> broken/crashing/vulnerable/..), not for the lulz nor breaking users.
>> I'm very sorry if that happened, only those who do nothing do not
>> break anything though.
>> Existing tests were still passing, but shit happens.
>>
>
> Then lets deal with it by adding more tests.
>
>
>>
>> >  We’re just racking up CVE’s, people are disabling the mfd parser
>> altogether, and it no longer support common use cases that people now
>> complain about because it supported cases in the wild that the new work
>> does not.
>>
>> Are there multiple issues? I know of the one reported in [1] about
>> "file upload does not work if any file fields are blank".
>> That's not actionable sorry (I don't understand what it means), no
>> more than your rant here and elusive "hints" on where/how to fix it.
>> I asked in the other thread for a reproducer in the form of a HTTP
>> payload, not a mod_perl handler which I don't know how to debug (let
>> alone without the right thing to send on the client side).
>>
>>
> I translated the bug report for you.  It involves browsers like Opera
> that send  filename=""
> attributes in the Content-Disposition header.  It's generating an
> accidental DoS, depending
> on how people use the upload API.  Toss in some tests into util.t and
> I'll add this one for you.
>
>
>> >
>> > With the latest code coming out of p5p for Perl, there’s a whole
>> new reason for excitement in httpd-land: the mod_perl2 + mpm_event
>> combination is rock solid and screaming fast with HTTP/2.  The only 
>> reason

Re: [libapreq2] nits to pick about the patches to util.c over the past few years

[Joe Schaefer]

Of course, I don’t know how to advise you regarding the security aspects,
since you’re doing what you thought was the right thing to do and put the
mfd parser into an error state instead of leaving well enough alone.  But
basically libapreq2 users get annoyed when the parser breaks on valid
input, and may get antsy when their server goes bonkers because they aren’t
in the habit of doing error handling on this condition.

On Sat, Oct 29, 2022 at 8:36 PM Joe Schaefer  wrote:

> Found the problem: it's just a misunderstanding about what is admissible
> in a successful file upload widget.
> If someone doesn't add a file to the upload widget, it is still a
> successful control and should be processed as such on the server.
> In this case, just like with opera, the filename attribute will be
> present, but set to an empty double-quoted string.
>
> Here's my patchset, enjoy.
>
>
>
>
>
>
>
>
>
> On Sat, Oct 29, 2022 at 2:47 PM Joe Schaefer  wrote:
>
>> Curiously, this doesn't seem to present any problems for
>> apreq_header_attribute in trunk/HEAD.  A good thing.
>>
>> That means we may need to look more closely at r1903484 in glue/perl.
>>
>> On Sat, Oct 29, 2022 at 2:12 PM Joe Schaefer  wrote:
>>
>>>
>>> On Sat, Oct 29, 2022 at 1:16 PM Joe Schaefer  wrote:
>>>


 On Sat, Oct 29, 2022 at 1:00 PM Yann Ylavic 
 wrote:

> Hi Joe,
>
> here comes the "goofer".
>
> On Fri, Oct 28, 2022 at 9:05 PM  wrote:
> >
> > Long time fan, not a first time caller.
>
> Yet what a crappy thread (and comments on [1]).
> All top posting, unreplyable.
>
> >
> > Libapreq2 was intended to be a safe,fast, standards compliant
> library- primarily *safe* before all other priorities.  Some of the work
> going on lately in util.c is starting to undermine that prime directive, 
> so
> I’d like to better understand why these changes are happening, and why 
> they
> are snowballing into a less functional, less secure software product that
> is driving up my support costs on CPAN.
>
> Yeah sure, rewriting history. That marvelous previous 2.16 just
> exploded when faced with google's oss-fuzzers (and not just a little,
> quite some reports) which now fuzz httpd trunk (thus apreq).
> CVE-2022-22728 is about libapreq2 v2.16 *and earlier" right? So
> something pre-dated my changes.


 Fair enough.


>
 >
> > For instance, this revision 1867789 is a pure pessimization:  it
> trades userland RAM for filesystem cache RAM, that’s it, but it’s not a 
> big
> deal.  Just churn.
>
> I call it a fix for an UAF (Use After Free). This is my only change in
> 2.16 btw, while you seem to suggest that security issues started with
> 2.16.
>
> >
> > Everything in the crufty, old apreq_header_attribute code I wrote
> was completely tossed and reimplemented.  Why?
>
> Someone had to address the security reports, and someone (me) dared
> touching your code because it was not safe (i.e.
> broken/crashing/vulnerable/..), not for the lulz nor breaking users.
> I'm very sorry if that happened, only those who do nothing do not
> break anything though.
> Existing tests were still passing, but shit happens.
>

 Then lets deal with it by adding more tests.


>
> >  We’re just racking up CVE’s, people are disabling the mfd parser
> altogether, and it no longer support common use cases that people now
> complain about because it supported cases in the wild that the new work
> does not.
>
> Are there multiple issues? I know of the one reported in [1] about
> "file upload does not work if any file fields are blank".
> That's not actionable sorry (I don't understand what it means), no
> more than your rant here and elusive "hints" on where/how to fix it.
> I asked in the other thread for a reproducer in the form of a HTTP
> payload, not a mod_perl handler which I don't know how to debug (let
> alone without the right thing to send on the client side).
>
>
 I translated the bug report for you.  It involves browsers like Opera
 that send  filename=""
 attributes in the Content-Disposition header.  It's generating an
 accidental DoS, depending
 on how people use the upload API.  Toss in some tests into util.t and
 I'll add this one for you.


> >
> > With the latest code coming out of p5p for Perl, there’s a whole new
> reason for excitement in httpd-land: the mod_perl2 + mpm_event combination
> is rock solid and screaming fast with HTTP/2.  The only reason I resubbed
> here is in the hopes of some synergy retaking these perl-related projects,
> since mod_perl2 is the only game in town for embedded interpreters in
> httpd2 (and no, lua is not the answer, it’s not thread safe either).
>
> Synergy! What a great 

Re: [libapreq2] nits to pick about the patches to util.c over the past few years

[Joe Schaefer]

Found the problem: it's just a misunderstanding about what is admissible in
a successful file upload widget.
If someone doesn't add a file to the upload widget, it is still a
successful control and should be processed as such on the server.
In this case, just like with opera, the filename attribute will be present,
but set to an empty double-quoted string.

Here's my patchset, enjoy.









On Sat, Oct 29, 2022 at 2:47 PM Joe Schaefer  wrote:

> Curiously, this doesn't seem to present any problems for
> apreq_header_attribute in trunk/HEAD.  A good thing.
>
> That means we may need to look more closely at r1903484 in glue/perl.
>
> On Sat, Oct 29, 2022 at 2:12 PM Joe Schaefer  wrote:
>
>>
>> On Sat, Oct 29, 2022 at 1:16 PM Joe Schaefer  wrote:
>>
>>>
>>>
>>> On Sat, Oct 29, 2022 at 1:00 PM Yann Ylavic 
>>> wrote:
>>>
 Hi Joe,

 here comes the "goofer".

 On Fri, Oct 28, 2022 at 9:05 PM  wrote:
 >
 > Long time fan, not a first time caller.

 Yet what a crappy thread (and comments on [1]).
 All top posting, unreplyable.

 >
 > Libapreq2 was intended to be a safe,fast, standards compliant
 library- primarily *safe* before all other priorities.  Some of the work
 going on lately in util.c is starting to undermine that prime directive, so
 I’d like to better understand why these changes are happening, and why they
 are snowballing into a less functional, less secure software product that
 is driving up my support costs on CPAN.

 Yeah sure, rewriting history. That marvelous previous 2.16 just
 exploded when faced with google's oss-fuzzers (and not just a little,
 quite some reports) which now fuzz httpd trunk (thus apreq).
 CVE-2022-22728 is about libapreq2 v2.16 *and earlier" right? So
 something pre-dated my changes.
>>>
>>>
>>> Fair enough.
>>>
>>>

>>> >
 > For instance, this revision 1867789 is a pure pessimization:  it
 trades userland RAM for filesystem cache RAM, that’s it, but it’s not a big
 deal.  Just churn.

 I call it a fix for an UAF (Use After Free). This is my only change in
 2.16 btw, while you seem to suggest that security issues started with
 2.16.

 >
 > Everything in the crufty, old apreq_header_attribute code I wrote was
 completely tossed and reimplemented.  Why?

 Someone had to address the security reports, and someone (me) dared
 touching your code because it was not safe (i.e.
 broken/crashing/vulnerable/..), not for the lulz nor breaking users.
 I'm very sorry if that happened, only those who do nothing do not
 break anything though.
 Existing tests were still passing, but shit happens.

>>>
>>> Then lets deal with it by adding more tests.
>>>
>>>

 >  We’re just racking up CVE’s, people are disabling the mfd parser
 altogether, and it no longer support common use cases that people now
 complain about because it supported cases in the wild that the new work
 does not.

 Are there multiple issues? I know of the one reported in [1] about
 "file upload does not work if any file fields are blank".
 That's not actionable sorry (I don't understand what it means), no
 more than your rant here and elusive "hints" on where/how to fix it.
 I asked in the other thread for a reproducer in the form of a HTTP
 payload, not a mod_perl handler which I don't know how to debug (let
 alone without the right thing to send on the client side).


>>> I translated the bug report for you.  It involves browsers like Opera
>>> that send  filename=""
>>> attributes in the Content-Disposition header.  It's generating an
>>> accidental DoS, depending
>>> on how people use the upload API.  Toss in some tests into util.t and
>>> I'll add this one for you.
>>>
>>>
 >
 > With the latest code coming out of p5p for Perl, there’s a whole new
 reason for excitement in httpd-land: the mod_perl2 + mpm_event combination
 is rock solid and screaming fast with HTTP/2.  The only reason I resubbed
 here is in the hopes of some synergy retaking these perl-related projects,
 since mod_perl2 is the only game in town for embedded interpreters in
 httpd2 (and no, lua is not the answer, it’s not thread safe either).

 Synergy! What a great intro..


 Regards;
 Yann.

 [1] https://rt.cpan.org/Public/Bug/Display.html?id=144470

>>>
>>>
>>> --
>>> Joe Schaefer, Ph.D.
>>> We only build what you need built.
>>> 
>>> 954.253.3732 
>>>
>>>
>>>
>>
>> Let's start with this (untested) patch...
>>
>>
>> Index: library/t/util.c
>> ===
>> --- library/t/util.c(revision 1904922)
>> +++ library/t/util.c(working copy)
>> @@ -271,6 +271,7 @@
>>  static void test_header_attribute(dAT, void *ctx)
>>  {
>>  const char hdr[] = "name=\"filename=foo\"; filename=\"quux.txt\"";
>> +

Re: [libapreq2] nits to pick about the patches to util.c over the past few years

[Joe Schaefer]

Curiously, this doesn't seem to present any problems for
apreq_header_attribute in trunk/HEAD.  A good thing.

That means we may need to look more closely at r1903484 in glue/perl.

On Sat, Oct 29, 2022 at 2:12 PM Joe Schaefer  wrote:

>
> On Sat, Oct 29, 2022 at 1:16 PM Joe Schaefer  wrote:
>
>>
>>
>> On Sat, Oct 29, 2022 at 1:00 PM Yann Ylavic  wrote:
>>
>>> Hi Joe,
>>>
>>> here comes the "goofer".
>>>
>>> On Fri, Oct 28, 2022 at 9:05 PM  wrote:
>>> >
>>> > Long time fan, not a first time caller.
>>>
>>> Yet what a crappy thread (and comments on [1]).
>>> All top posting, unreplyable.
>>>
>>> >
>>> > Libapreq2 was intended to be a safe,fast, standards compliant library-
>>> primarily *safe* before all other priorities.  Some of the work going on
>>> lately in util.c is starting to undermine that prime directive, so I’d like
>>> to better understand why these changes are happening, and why they are
>>> snowballing into a less functional, less secure software product that is
>>> driving up my support costs on CPAN.
>>>
>>> Yeah sure, rewriting history. That marvelous previous 2.16 just
>>> exploded when faced with google's oss-fuzzers (and not just a little,
>>> quite some reports) which now fuzz httpd trunk (thus apreq).
>>> CVE-2022-22728 is about libapreq2 v2.16 *and earlier" right? So
>>> something pre-dated my changes.
>>
>>
>> Fair enough.
>>
>>
>>>
>> >
>>> > For instance, this revision 1867789 is a pure pessimization:  it
>>> trades userland RAM for filesystem cache RAM, that’s it, but it’s not a big
>>> deal.  Just churn.
>>>
>>> I call it a fix for an UAF (Use After Free). This is my only change in
>>> 2.16 btw, while you seem to suggest that security issues started with
>>> 2.16.
>>>
>>> >
>>> > Everything in the crufty, old apreq_header_attribute code I wrote was
>>> completely tossed and reimplemented.  Why?
>>>
>>> Someone had to address the security reports, and someone (me) dared
>>> touching your code because it was not safe (i.e.
>>> broken/crashing/vulnerable/..), not for the lulz nor breaking users.
>>> I'm very sorry if that happened, only those who do nothing do not
>>> break anything though.
>>> Existing tests were still passing, but shit happens.
>>>
>>
>> Then lets deal with it by adding more tests.
>>
>>
>>>
>>> >  We’re just racking up CVE’s, people are disabling the mfd parser
>>> altogether, and it no longer support common use cases that people now
>>> complain about because it supported cases in the wild that the new work
>>> does not.
>>>
>>> Are there multiple issues? I know of the one reported in [1] about
>>> "file upload does not work if any file fields are blank".
>>> That's not actionable sorry (I don't understand what it means), no
>>> more than your rant here and elusive "hints" on where/how to fix it.
>>> I asked in the other thread for a reproducer in the form of a HTTP
>>> payload, not a mod_perl handler which I don't know how to debug (let
>>> alone without the right thing to send on the client side).
>>>
>>>
>> I translated the bug report for you.  It involves browsers like Opera
>> that send  filename=""
>> attributes in the Content-Disposition header.  It's generating an
>> accidental DoS, depending
>> on how people use the upload API.  Toss in some tests into util.t and
>> I'll add this one for you.
>>
>>
>>> >
>>> > With the latest code coming out of p5p for Perl, there’s a whole new
>>> reason for excitement in httpd-land: the mod_perl2 + mpm_event combination
>>> is rock solid and screaming fast with HTTP/2.  The only reason I resubbed
>>> here is in the hopes of some synergy retaking these perl-related projects,
>>> since mod_perl2 is the only game in town for embedded interpreters in
>>> httpd2 (and no, lua is not the answer, it’s not thread safe either).
>>>
>>> Synergy! What a great intro..
>>>
>>>
>>> Regards;
>>> Yann.
>>>
>>> [1] https://rt.cpan.org/Public/Bug/Display.html?id=144470
>>>
>>
>>
>> --
>> Joe Schaefer, Ph.D.
>> We only build what you need built.
>> 
>> 954.253.3732 
>>
>>
>>
>
> Let's start with this (untested) patch...
>
>
> Index: library/t/util.c
> ===
> --- library/t/util.c(revision 1904922)
> +++ library/t/util.c(working copy)
> @@ -271,6 +271,7 @@
>  static void test_header_attribute(dAT, void *ctx)
>  {
>  const char hdr[] = "name=\"filename=foo\"; filename=\"quux.txt\"";
> +const char opera[] = "name=\"foo\"; filename=\"\"";
>  const char *val;
>  apr_size_t vlen;
>
> @@ -284,6 +285,10 @@
>  AT_int_eq(vlen, 8);
>  AT_mem_eq("quux.txt", val, 8);
>
> +AT_int_eq(apreq_header_attribute(opera, "filename" 8, , ),
> +  APR_SUCCESS);
> +AT_int_eq(vlen,0);
> +
>  }
>
>  static void test_brigade_concat(dAT, void *ctx)
> @@ -315,7 +320,7 @@
>  { dT(test_join, 0) },
>  { dT(test_brigade_fwrite, 0) },
>  { dT(test_file_mktemp, 0) },
> -{ dT(test_header_attribute, 6) },
> +{ 

Re: [libapreq2] nits to pick about the patches to util.c over the past few years

[Joe Schaefer]

On Sat, Oct 29, 2022 at 1:16 PM Joe Schaefer  wrote:

>
>
> On Sat, Oct 29, 2022 at 1:00 PM Yann Ylavic  wrote:
>
>> Hi Joe,
>>
>> here comes the "goofer".
>>
>> On Fri, Oct 28, 2022 at 9:05 PM  wrote:
>> >
>> > Long time fan, not a first time caller.
>>
>> Yet what a crappy thread (and comments on [1]).
>> All top posting, unreplyable.
>>
>> >
>> > Libapreq2 was intended to be a safe,fast, standards compliant library-
>> primarily *safe* before all other priorities.  Some of the work going on
>> lately in util.c is starting to undermine that prime directive, so I’d like
>> to better understand why these changes are happening, and why they are
>> snowballing into a less functional, less secure software product that is
>> driving up my support costs on CPAN.
>>
>> Yeah sure, rewriting history. That marvelous previous 2.16 just
>> exploded when faced with google's oss-fuzzers (and not just a little,
>> quite some reports) which now fuzz httpd trunk (thus apreq).
>> CVE-2022-22728 is about libapreq2 v2.16 *and earlier" right? So
>> something pre-dated my changes.
>
>
> Fair enough.
>
>
>>
> >
>> > For instance, this revision 1867789 is a pure pessimization:  it trades
>> userland RAM for filesystem cache RAM, that’s it, but it’s not a big deal.
>> Just churn.
>>
>> I call it a fix for an UAF (Use After Free). This is my only change in
>> 2.16 btw, while you seem to suggest that security issues started with
>> 2.16.
>>
>> >
>> > Everything in the crufty, old apreq_header_attribute code I wrote was
>> completely tossed and reimplemented.  Why?
>>
>> Someone had to address the security reports, and someone (me) dared
>> touching your code because it was not safe (i.e.
>> broken/crashing/vulnerable/..), not for the lulz nor breaking users.
>> I'm very sorry if that happened, only those who do nothing do not
>> break anything though.
>> Existing tests were still passing, but shit happens.
>>
>
> Then lets deal with it by adding more tests.
>
>
>>
>> >  We’re just racking up CVE’s, people are disabling the mfd parser
>> altogether, and it no longer support common use cases that people now
>> complain about because it supported cases in the wild that the new work
>> does not.
>>
>> Are there multiple issues? I know of the one reported in [1] about
>> "file upload does not work if any file fields are blank".
>> That's not actionable sorry (I don't understand what it means), no
>> more than your rant here and elusive "hints" on where/how to fix it.
>> I asked in the other thread for a reproducer in the form of a HTTP
>> payload, not a mod_perl handler which I don't know how to debug (let
>> alone without the right thing to send on the client side).
>>
>>
> I translated the bug report for you.  It involves browsers like Opera that
> send  filename=""
> attributes in the Content-Disposition header.  It's generating an
> accidental DoS, depending
> on how people use the upload API.  Toss in some tests into util.t and I'll
> add this one for you.
>
>
>> >
>> > With the latest code coming out of p5p for Perl, there’s a whole new
>> reason for excitement in httpd-land: the mod_perl2 + mpm_event combination
>> is rock solid and screaming fast with HTTP/2.  The only reason I resubbed
>> here is in the hopes of some synergy retaking these perl-related projects,
>> since mod_perl2 is the only game in town for embedded interpreters in
>> httpd2 (and no, lua is not the answer, it’s not thread safe either).
>>
>> Synergy! What a great intro..
>>
>>
>> Regards;
>> Yann.
>>
>> [1] https://rt.cpan.org/Public/Bug/Display.html?id=144470
>>
>
>
> --
> Joe Schaefer, Ph.D.
> We only build what you need built.
> 
> 954.253.3732 
>
>
>

Let's start with this (untested) patch...


Index: library/t/util.c
===
--- library/t/util.c(revision 1904922)
+++ library/t/util.c(working copy)
@@ -271,6 +271,7 @@
 static void test_header_attribute(dAT, void *ctx)
 {
 const char hdr[] = "name=\"filename=foo\"; filename=\"quux.txt\"";
+const char opera[] = "name=\"foo\"; filename=\"\"";
 const char *val;
 apr_size_t vlen;

@@ -284,6 +285,10 @@
 AT_int_eq(vlen, 8);
 AT_mem_eq("quux.txt", val, 8);

+AT_int_eq(apreq_header_attribute(opera, "filename" 8, , ),
+  APR_SUCCESS);
+AT_int_eq(vlen,0);
+
 }

 static void test_brigade_concat(dAT, void *ctx)
@@ -315,7 +320,7 @@
 { dT(test_join, 0) },
 { dT(test_brigade_fwrite, 0) },
 { dT(test_file_mktemp, 0) },
-{ dT(test_header_attribute, 6) },
+{ dT(test_header_attribute, 8) },
 { dT(test_brigade_concat, 0) },
 };
-- 
Joe Schaefer, Ph.D.
We only build what you need built.

954.253.3732 

Re: [libapreq2] nits to pick about the patches to util.c over the past few years

[Joe Schaefer]

Thanks for the tip! It's actually pretty good news that the only thing
google's fuzzer is complaining about is the very small piece of the puzzle.
We just need to get it right this time.

On Sat, Oct 29, 2022 at 1:38 PM Greg Stein  wrote:

> F/OSS is not about telling others how to write their code, Joe. You know
> this. And it *definitely* is not about demanding they spend *their* time to
> fix your pet issues.
>
> If you have a problem with the code, then supply a fix. Your dozen emails
> are not fixing anything, and are certainly not endearing anybody to help
> you. Be nice, if you want help.
>
> -g
>
>
> On Sat, Oct 29, 2022 at 11:11 AM Joe Schaefer  wrote:
>
>> ...fell apart when Max asked you to release his patch to my screwup with
>> the NPE, and instead of cutting a release
>> with just that patch applied, you began the tragic process of dorking
>> around with apreq_header_attribute() as well.
>>
>> Just pull all those hacks out of apreq/trunk, and release exactly what
>> Max told you to release, and you will be good for another quiet decade of
>> happy libapreq2 users.
>>
>> If you do not take this advice, at least for your own personal
>> reputations, stop hacking the logic and  start writing regression tests.
>>  An internet-grade mfd parser is only as good as its weakest link, and I
>> just spent the past day telling you where that is.
>>
>> On Sat, Oct 29, 2022 at 12:06 PM Joe Schaefer  wrote:
>>
>>> All we need to do at this point is remember the basics of how to cut a
>>> security bugfix release.  Everything in libapreq
>>>
>>> On Fri, Oct 28, 2022 at 3:04 PM  wrote:
>>>
 Long time fan, not a first time caller.



 Libapreq2 was intended to be a safe,fast, standards compliant library-
 primarily **safe** before all other priorities.  Some of the work
 going on lately in util.c is starting to undermine that prime directive, so
 I’d like to better understand why these changes are happening, and why they
 are snowballing into a less functional, less secure software product that
 is driving up my support costs on CPAN.



 For instance, this revision 1867789 is a pure pessimization:  it trades
 userland RAM for filesystem cache RAM, that’s it, but it’s not a big deal.
 Just churn.



 Everything in the crufty, old apreq_header_attribute code I wrote was
 completely tossed and reimplemented.  Why?  We’re just racking up CVE’s,
 people are disabling the mfd parser altogether, and it no longer support
 common use cases that people now complain about because it supported cases
 in the wild that the new work does not.



 With the latest code coming out of p5p for Perl, there’s a whole new
 reason for excitement in httpd-land: the mod_perl2 + mpm_event combination
 is rock solid and screaming fast with HTTP/2.  The only reason I resubbed
 here is in the hopes of some synergy retaking these perl-related projects,
 since mod_perl2 is the only game in town for embedded interpreters in
 httpd2 (and no, lua is not the answer, it’s not thread safe either).





 Joe Schaefer, Ph.D.

 

 954.253.3732 

 SunStar Systems CMS  *- The Original
 Markdown JAM Stack**™*



>>>
>>>
>>> --
>>> Joe Schaefer, Ph.D.
>>> We only build what you need built.
>>> 
>>> 954.253.3732 
>>>
>>>
>>>
>>
>> --
>> Joe Schaefer, Ph.D.
>> We only build what you need built.
>> 
>> 954.253.3732 
>>
>>
>>

-- 
Joe Schaefer, Ph.D.
We only build what you need built.

954.253.3732 

Re: [libapreq2] nits to pick about the patches to util.c over the past few years

[Greg Stein]

F/OSS is not about telling others how to write their code, Joe. You know
this. And it *definitely* is not about demanding they spend *their* time to
fix your pet issues.

If you have a problem with the code, then supply a fix. Your dozen emails
are not fixing anything, and are certainly not endearing anybody to help
you. Be nice, if you want help.

-g


On Sat, Oct 29, 2022 at 11:11 AM Joe Schaefer  wrote:

> ...fell apart when Max asked you to release his patch to my screwup with
> the NPE, and instead of cutting a release
> with just that patch applied, you began the tragic process of dorking
> around with apreq_header_attribute() as well.
>
> Just pull all those hacks out of apreq/trunk, and release exactly what Max
> told you to release, and you will be good for another quiet decade of happy
> libapreq2 users.
>
> If you do not take this advice, at least for your own personal
> reputations, stop hacking the logic and  start writing regression tests.
>  An internet-grade mfd parser is only as good as its weakest link, and I
> just spent the past day telling you where that is.
>
> On Sat, Oct 29, 2022 at 12:06 PM Joe Schaefer  wrote:
>
>> All we need to do at this point is remember the basics of how to cut a
>> security bugfix release.  Everything in libapreq
>>
>> On Fri, Oct 28, 2022 at 3:04 PM  wrote:
>>
>>> Long time fan, not a first time caller.
>>>
>>>
>>>
>>> Libapreq2 was intended to be a safe,fast, standards compliant library-
>>> primarily **safe** before all other priorities.  Some of the work going
>>> on lately in util.c is starting to undermine that prime directive, so I’d
>>> like to better understand why these changes are happening, and why they are
>>> snowballing into a less functional, less secure software product that is
>>> driving up my support costs on CPAN.
>>>
>>>
>>>
>>> For instance, this revision 1867789 is a pure pessimization:  it trades
>>> userland RAM for filesystem cache RAM, that’s it, but it’s not a big deal.
>>> Just churn.
>>>
>>>
>>>
>>> Everything in the crufty, old apreq_header_attribute code I wrote was
>>> completely tossed and reimplemented.  Why?  We’re just racking up CVE’s,
>>> people are disabling the mfd parser altogether, and it no longer support
>>> common use cases that people now complain about because it supported cases
>>> in the wild that the new work does not.
>>>
>>>
>>>
>>> With the latest code coming out of p5p for Perl, there’s a whole new
>>> reason for excitement in httpd-land: the mod_perl2 + mpm_event combination
>>> is rock solid and screaming fast with HTTP/2.  The only reason I resubbed
>>> here is in the hopes of some synergy retaking these perl-related projects,
>>> since mod_perl2 is the only game in town for embedded interpreters in
>>> httpd2 (and no, lua is not the answer, it’s not thread safe either).
>>>
>>>
>>>
>>>
>>>
>>> Joe Schaefer, Ph.D.
>>>
>>> 
>>>
>>> 954.253.3732 
>>>
>>> SunStar Systems CMS  *- The Original
>>> Markdown JAM Stack**™*
>>>
>>>
>>>
>>
>>
>> --
>> Joe Schaefer, Ph.D.
>> We only build what you need built.
>> 
>> 954.253.3732 
>>
>>
>>
>
> --
> Joe Schaefer, Ph.D.
> We only build what you need built.
> 
> 954.253.3732 
>
>
>

Re: [libapreq2] nits to pick about the patches to util.c over the past few years

[Joe Schaefer]

On Sat, Oct 29, 2022 at 1:00 PM Yann Ylavic  wrote:

> Hi Joe,
>
> here comes the "goofer".
>
> On Fri, Oct 28, 2022 at 9:05 PM  wrote:
> >
> > Long time fan, not a first time caller.
>
> Yet what a crappy thread (and comments on [1]).
> All top posting, unreplyable.
>
> >
> > Libapreq2 was intended to be a safe,fast, standards compliant library-
> primarily *safe* before all other priorities.  Some of the work going on
> lately in util.c is starting to undermine that prime directive, so I’d like
> to better understand why these changes are happening, and why they are
> snowballing into a less functional, less secure software product that is
> driving up my support costs on CPAN.
>
> Yeah sure, rewriting history. That marvelous previous 2.16 just
> exploded when faced with google's oss-fuzzers (and not just a little,
> quite some reports) which now fuzz httpd trunk (thus apreq).
> CVE-2022-22728 is about libapreq2 v2.16 *and earlier" right? So
> something pre-dated my changes.


Fair enough.


>
>
> > For instance, this revision 1867789 is a pure pessimization:  it trades
> userland RAM for filesystem cache RAM, that’s it, but it’s not a big deal.
> Just churn.
>
> I call it a fix for an UAF (Use After Free). This is my only change in
> 2.16 btw, while you seem to suggest that security issues started with
> 2.16.
>
> >
> > Everything in the crufty, old apreq_header_attribute code I wrote was
> completely tossed and reimplemented.  Why?
>
> Someone had to address the security reports, and someone (me) dared
> touching your code because it was not safe (i.e.
> broken/crashing/vulnerable/..), not for the lulz nor breaking users.
> I'm very sorry if that happened, only those who do nothing do not
> break anything though.
> Existing tests were still passing, but shit happens.
>

Then lets deal with it by adding more tests.


>
> >  We’re just racking up CVE’s, people are disabling the mfd parser
> altogether, and it no longer support common use cases that people now
> complain about because it supported cases in the wild that the new work
> does not.
>
> Are there multiple issues? I know of the one reported in [1] about
> "file upload does not work if any file fields are blank".
> That's not actionable sorry (I don't understand what it means), no
> more than your rant here and elusive "hints" on where/how to fix it.
> I asked in the other thread for a reproducer in the form of a HTTP
> payload, not a mod_perl handler which I don't know how to debug (let
> alone without the right thing to send on the client side).
>
>
I translated the bug report for you.  It involves browsers like Opera that
send  filename=""
attributes in the Content-Disposition header.  It's generating an
accidental DoS, depending
on how people use the upload API.  Toss in some tests into util.t and I'll
add this one for you.


> >
> > With the latest code coming out of p5p for Perl, there’s a whole new
> reason for excitement in httpd-land: the mod_perl2 + mpm_event combination
> is rock solid and screaming fast with HTTP/2.  The only reason I resubbed
> here is in the hopes of some synergy retaking these perl-related projects,
> since mod_perl2 is the only game in town for embedded interpreters in
> httpd2 (and no, lua is not the answer, it’s not thread safe either).
>
> Synergy! What a great intro..
>
>
> Regards;
> Yann.
>
> [1] https://rt.cpan.org/Public/Bug/Display.html?id=144470
>


-- 
Joe Schaefer, Ph.D.
We only build what you need built.

954.253.3732 

Re: [libapreq2] nits to pick about the patches to util.c over the past few years

[Yann Ylavic]

Hi Joe,

here comes the "goofer".

On Fri, Oct 28, 2022 at 9:05 PM  wrote:
>
> Long time fan, not a first time caller.

Yet what a crappy thread (and comments on [1]).
All top posting, unreplyable.

>
> Libapreq2 was intended to be a safe,fast, standards compliant library- 
> primarily *safe* before all other priorities.  Some of the work going on 
> lately in util.c is starting to undermine that prime directive, so I’d like 
> to better understand why these changes are happening, and why they are 
> snowballing into a less functional, less secure software product that is 
> driving up my support costs on CPAN.

Yeah sure, rewriting history. That marvelous previous 2.16 just
exploded when faced with google's oss-fuzzers (and not just a little,
quite some reports) which now fuzz httpd trunk (thus apreq).
CVE-2022-22728 is about libapreq2 v2.16 *and earlier" right? So
something pre-dated my changes.

>
> For instance, this revision 1867789 is a pure pessimization:  it trades 
> userland RAM for filesystem cache RAM, that’s it, but it’s not a big deal.  
> Just churn.

I call it a fix for an UAF (Use After Free). This is my only change in
2.16 btw, while you seem to suggest that security issues started with
2.16.

>
> Everything in the crufty, old apreq_header_attribute code I wrote was 
> completely tossed and reimplemented.  Why?

Someone had to address the security reports, and someone (me) dared
touching your code because it was not safe (i.e.
broken/crashing/vulnerable/..), not for the lulz nor breaking users.
I'm very sorry if that happened, only those who do nothing do not
break anything though.
Existing tests were still passing, but shit happens.

>  We’re just racking up CVE’s, people are disabling the mfd parser altogether, 
> and it no longer support common use cases that people now complain about 
> because it supported cases in the wild that the new work does not.

Are there multiple issues? I know of the one reported in [1] about
"file upload does not work if any file fields are blank".
That's not actionable sorry (I don't understand what it means), no
more than your rant here and elusive "hints" on where/how to fix it.
I asked in the other thread for a reproducer in the form of a HTTP
payload, not a mod_perl handler which I don't know how to debug (let
alone without the right thing to send on the client side).

>
> With the latest code coming out of p5p for Perl, there’s a whole new reason 
> for excitement in httpd-land: the mod_perl2 + mpm_event combination is rock 
> solid and screaming fast with HTTP/2.  The only reason I resubbed here is in 
> the hopes of some synergy retaking these perl-related projects, since 
> mod_perl2 is the only game in town for embedded interpreters in httpd2 (and 
> no, lua is not the answer, it’s not thread safe either).

Synergy! What a great intro..


Regards;
Yann.

[1] https://rt.cpan.org/Public/Bug/Display.html?id=144470

Re: [libapreq2] nits to pick about the patches to util.c over the past few years

[Joe Schaefer]

...fell apart when Max asked you to release his patch to my screwup with
the NPE, and instead of cutting a release
with just that patch applied, you began the tragic process of dorking
around with apreq_header_attribute() as well.

Just pull all those hacks out of apreq/trunk, and release exactly what Max
told you to release, and you will be good for another quiet decade of happy
libapreq2 users.

If you do not take this advice, at least for your own personal reputations,
stop hacking the logic and  start writing regression tests.
 An internet-grade mfd parser is only as good as its weakest link, and I
just spent the past day telling you where that is.

On Sat, Oct 29, 2022 at 12:06 PM Joe Schaefer  wrote:

> All we need to do at this point is remember the basics of how to cut a
> security bugfix release.  Everything in libapreq
>
> On Fri, Oct 28, 2022 at 3:04 PM  wrote:
>
>> Long time fan, not a first time caller.
>>
>>
>>
>> Libapreq2 was intended to be a safe,fast, standards compliant library-
>> primarily **safe** before all other priorities.  Some of the work going
>> on lately in util.c is starting to undermine that prime directive, so I’d
>> like to better understand why these changes are happening, and why they are
>> snowballing into a less functional, less secure software product that is
>> driving up my support costs on CPAN.
>>
>>
>>
>> For instance, this revision 1867789 is a pure pessimization:  it trades
>> userland RAM for filesystem cache RAM, that’s it, but it’s not a big deal.
>> Just churn.
>>
>>
>>
>> Everything in the crufty, old apreq_header_attribute code I wrote was
>> completely tossed and reimplemented.  Why?  We’re just racking up CVE’s,
>> people are disabling the mfd parser altogether, and it no longer support
>> common use cases that people now complain about because it supported cases
>> in the wild that the new work does not.
>>
>>
>>
>> With the latest code coming out of p5p for Perl, there’s a whole new
>> reason for excitement in httpd-land: the mod_perl2 + mpm_event combination
>> is rock solid and screaming fast with HTTP/2.  The only reason I resubbed
>> here is in the hopes of some synergy retaking these perl-related projects,
>> since mod_perl2 is the only game in town for embedded interpreters in
>> httpd2 (and no, lua is not the answer, it’s not thread safe either).
>>
>>
>>
>>
>>
>> Joe Schaefer, Ph.D.
>>
>> 
>>
>> 954.253.3732 
>>
>> SunStar Systems CMS  *- The Original
>> Markdown JAM Stack**™*
>>
>>
>>
>
>
> --
> Joe Schaefer, Ph.D.
> We only build what you need built.
> 
> 954.253.3732 
>
>
>

-- 
Joe Schaefer, Ph.D.
We only build what you need built.

954.253.3732 

Re: [libapreq2] nits to pick about the patches to util.c over the past few years

[Joe Schaefer]

All we need to do at this point is remember the basics of how to cut a
security bugfix release.  Everything in libapreq

On Fri, Oct 28, 2022 at 3:04 PM  wrote:

> Long time fan, not a first time caller.
>
>
>
> Libapreq2 was intended to be a safe,fast, standards compliant library-
> primarily **safe** before all other priorities.  Some of the work going
> on lately in util.c is starting to undermine that prime directive, so I’d
> like to better understand why these changes are happening, and why they are
> snowballing into a less functional, less secure software product that is
> driving up my support costs on CPAN.
>
>
>
> For instance, this revision 1867789 is a pure pessimization:  it trades
> userland RAM for filesystem cache RAM, that’s it, but it’s not a big deal.
> Just churn.
>
>
>
> Everything in the crufty, old apreq_header_attribute code I wrote was
> completely tossed and reimplemented.  Why?  We’re just racking up CVE’s,
> people are disabling the mfd parser altogether, and it no longer support
> common use cases that people now complain about because it supported cases
> in the wild that the new work does not.
>
>
>
> With the latest code coming out of p5p for Perl, there’s a whole new
> reason for excitement in httpd-land: the mod_perl2 + mpm_event combination
> is rock solid and screaming fast with HTTP/2.  The only reason I resubbed
> here is in the hopes of some synergy retaking these perl-related projects,
> since mod_perl2 is the only game in town for embedded interpreters in
> httpd2 (and no, lua is not the answer, it’s not thread safe either).
>
>
>
>
>
> Joe Schaefer, Ph.D.
>
> 
>
> 954.253.3732 
>
> SunStar Systems CMS  *- The Original
> Markdown JAM Stack**™*
>
>
>


-- 
Joe Schaefer, Ph.D.
We only build what you need built.

954.253.3732