Hello,
I can confirm the issue is fixed. Do you have a policy to backport the
patch at least to the latest stable?
Regards,
On 10/17/2016 11:45 PM, Aki Tuomi wrote:
>>>>>>>>> On 10/16/2016 11:16 PM, Pierre Jaury wrote:
>>>>>>>>>> Hello,
>>>>>>>>>>
>>>>>>>>>> I am using a dict proxy for my sieve extdata plugin to access some
>>>>>>>>>> fields from an SQLite database (autoreply text and other
>>>>>>>>>> database-configured items).
>>>>>>>>>>
>>>>>>>>>> All tests are performed against version 2.2.25.
>>>>>>>>>>
>>>>>>>>>> $ dovecot --version
>>>>>>>>>> 2.2.25 (7be1766)
>>>>>>>>>>
>>>>>>>>>> My configuration looks like:
>>>>>>>>>>
>>>>>>>>>> dict {
>>>>>>>>>> sieve = sqlite:/etc/dovecot/pigeonhole-sieve.dict
>>>>>>>>>> }
>>>>>>>>>>
>>>>>>>>>> [...]
>>>>>>>>>> sieve_extdata_dict_uri = proxy::sieve
>>>>>>>>>>
>>>>>>>>>> I am able to read pretty much any attribute without any issue, except
>>>>>>>>>> when the value contains a special character like "\r" or "\n". By
>>>>>>>>>> using
>>>>>>>>>> the doveadm dict client, I narrowed it down to the dictionary
>>>>>>>>>> management
>>>>>>>>>> part (either server, protocol or client).
>>>>>>>>>>
>>>>>>>>>> I was suspecting escaping functions from "lib/strescape.c" (mostly
>>>>>>>>>> str_tabescape and its counterpart, used by "lib-dict/client.c"), so I
>>>>>>>>>> monitored socket communications. It seems that escaping is done
>>>>>>>>>> properly
>>>>>>>>>> on the server and the socket is not an issue either.
>>>>>>>>>>
>>>>>>>>>> The following strace dump results from running "doveadm dict get"
>>>>>>>>>> against the dict socket:
>>>>>>>>>>
>>>>>>>>>> connect(8, {sa_family=AF_UNIX, sun_path="..."}, 110) = 0
>>>>>>>>>> fstat(8, {st_mode=S_IFSOCK|0777, st_size=0, ...}) = 0
>>>>>>>>>> [...]
>>>>>>>>>> write(8, "H2\t0\t0\tad...@domain.tld\tsieve\n", 30) = 30
>>>>>>>>>> [...]
>>>>>>>>>> read(8, "Otest\1r\1ntest\n", 8192) = 14
>>>>>>>>>>
>>>>>>>>>> Indeed "\1r" and "\1n" are the escape sequences used by
>>>>>>>>>> "lib/strescape.c". I went deeped and debugged the call to
>>>>>>>>>> "dict_lookup"
>>>>>>>>>> performed by doveadm. Indeed the client gets the proper string from
>>>>>>>>>> the
>>>>>>>>>> socket and to my surprise, it is properly unescaped.
>>>>>>>>>>
>>>>>>>>>> Then, in "client_dict_lookup" ("lib-dict/dict-client.c"), the call to
>>>>>>>>>> "p_strdup" returns an empty string (null byte set at the target
>>>>>>>>>> address).
>>>>>>>>>>
>>>>>>>>>> Before the call to the dict "->lookup" attribute
>>>>>>>>>> (client_dict_lookup):
>>>>>>>>>>
>>>>>>>>>> RAX: 0x7ffff73a37c0 (push r14)
>>>>>>>>>> RBX: 0x6831b8 ("priv/reply_body")
>>>>>>>>>> RCX: 0x7fffffffe240 --> 0x682a60 --> 0x6831b8 ("priv/reply_body")
>>>>>>>>>> RDX: 0x6831b8 ("priv/reply_body")
>>>>>>>>>> RSI: 0x683288 --> 0x7ffff7653120 --> 0x7ffff73ea620 ([...])
>>>>>>>>>> RDI: 0x690ad0 --> 0x7ffff7400713 --> 0x75250079786f7270 ('proxy')
>>>>>>>>>>
>>>>>>>>>> 0x7ffff73a1f10 <dict_lookup+32>: mov rcx,r11 (value_r)
>>>>>>>>>> 0x7ffff73a1f13 <dict_lookup+35>: mov rdx,r8 (key)
>>>>>>>>>> 0x7ffff73a1f16 <dict_lookup+38>: mov rsi,r10 (pool)
>>>>>>>>>> 0x7ffff73a1f19 <dict_lookup+41>: mov rdi,r9 (dict)
>>>>>>>>>> 0x7ffff73a1f1c <dict_lookup+44>: add rsp,0x8
>>>>>>>>>> => 0x7ffff73a1f20 <dict_lookup+48>: jmp rax
>>>>>>>>>>
>>>>>>>>>> Before the call to p_strdup in "client_dict_lookup":
>>>>>>>>>>
>>>>>>>>>> RSI: 0x6832d8 ("test\r\ntest") (lookup.result.value)
>>>>>>>>>> RDI: 0x683288 --> 0x7ffff7653120 --> [...] (pool)
>>>>>>>>>> RAX: 0x0 (result)
>>>>>>>>>>
>>>>>>>>>> 0x7ffff73a384f: nop
>>>>>>>>>> 0x7ffff73a3850: mov rsi,QWORD PTR [rsp+0x8]
>>>>>>>>>> 0x7ffff73a3855: mov rdi,r14
>>>>>>>>>> => 0x7ffff73a3858: call 0x7ffff736d3c0 <p_strdup@plt>
>>>>>>>>>> 0x7ffff73a385d: mov QWORD PTR [r13+0x0],rax
>>>>>>>>>> 0x7ffff73a3861: mov rsi,QWORD PTR [rsp+0x18]
>>>>>>>>>> 0x7ffff73a3866: xor rsi,QWORD PTR fs:0x28
>>>>>>>>>> 0x7ffff73a386f: mov eax,ebx
>>>>>>>>>>
>>>>>>>>>> After the call:
>>>>>>>>>>
>>>>>>>>>> 0x7ffff73a3850: mov rsi,QWORD PTR [rsp+0x8]
>>>>>>>>>> 0x7ffff73a3855: mov rdi,r14
>>>>>>>>>> 0x7ffff73a3858: call 0x7ffff736d3c0 <p_strdup@plt>
>>>>>>>>>> => 0x7ffff73a385d: mov QWORD PTR [r13+0x0],rax
>>>>>>>>>> 0x7ffff73a3861: mov rsi,QWORD PTR [rsp+0x18]
>>>>>>>>>> 0x7ffff73a3866: xor rsi,QWORD PTR fs:0x28
>>>>>>>>>> 0x7ffff73a386f: mov eax,ebx
>>>>>>>>>> 0x7ffff73a3871: jne 0x7ffff73a38da
>>>>>>>>>>
>>>>>>>>>> RSI: 0x0
>>>>>>>>>> RDI: 0x6832d8 --> 0x0
>>>>>>>>>> RAX: 0x6832d8 --> 0x0 (result)
>>>>>>>>>>
>>>>>>>>>> It is worth noting that I can reproduce the exact same execution flow
>>>>>>>>>> with a non-multiline result string (lookup.result.value) that is
>>>>>>>>>> properly copied by "p_strdup" and returned in RAX, then displayed by
>>>>>>>>>> doveadm.
>>>>>>>>>>
>>>>>>>>>> I am not familiar with the pooling mechanism hidden behind the call
>>>>>>>>>> to
>>>>>>>>>> p_strdump and not quite sure why this behaviour is emerging. Maybe I
>>>>>>>>>> am
>>>>>>>>>> even miles away from an understanding of the issue here, but it
>>>>>>>>>> sounds
>>>>>>>>>> to me like something is wrong in the way "p_strdup" performs the
>>>>>>>>>> copy.
>>>>>>>>>>
>>>>>>>>>> Hope this helps,
>>>>>>>>>> kaiyou.
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>>
>
> Fixed with
> https://github.com/dovecot/core/commit/4f051c3082080b9d69ef12c3720c683cff34b0da
>
> Aki Tuomi
>
