pg.ddx.io pgsql-hackers@postgresql.org mailing list archive help / color / mirror / Atom feed From: Maksim Milyutin <milyutinma@gmail.com>
To: Andrey Borodin <x4mmm@yandex-team.ru>
Cc: PostgreSQL mailing lists <pgsql-hackers@postgresql.org>
Subject: Re: [HACKERS] wrong t_bits alignment in pageinspect
Date: Thu, 4 Jan 2018 21:06:09 +0300
Message-ID: <da8b621a-ebbd-4fe6-c436-130cc8beb0a0@gmail.com> (raw )
In-Reply-To: <9B8647CA-7097-4A8C-9721-6DFAEE93D6AA@yandex-team.ru >
References: <ec295792-a69f-350f-6287-25a20e8f31d5@gmail.com >
<9B8647CA-7097-4A8C-9721-6DFAEE93D6AA@yandex-team.ru >
Hi!
02.01.2018 12:33, Andrey Borodin wrote:
>> 15 дек. 2017 г., в 18:53, Maksim Milyutin <milyutinma@gmail.com> написал(а):
>>
>> I found out the problem in exposing values of t_bits field from heap_page_items function.
> Probably, this [0] place contains similar bug too?
>
> [0] https://github.com/postgres/postgres/blob/master/contrib/pageinspect/heapfuncs.c#L439
Yes, it's so. Thanks a lot for notice.
Attached a new version of patch with regression test.
--
Regards,
Maksim Milyutin
Attachments:
pageinspect_tbits_alignment_fix_v2.patch (text/plain, 3.7K) download
diff --git a/contrib/pageinspect/expected/page.out b/contrib/pageinspect/expected/page.out
index 8e15947a81..97af6f5bd2 100644
--- a/contrib/pageinspect/expected/page.out
+++ b/contrib/pageinspect/expected/page.out
@@ -92,3 +92,20 @@ create table test_part1 partition of test_partitioned for values from ( 1 ) to (
select get_raw_page('test_part1', 0); -- get farther and error about empty table
ERROR: block number 0 is out of range for relation "test_part1"
drop table test_partitioned;
+-- check null bitmap alignment for table whose the number of attributes is multiple of 8
+create table test8 (f1 int, f2 int, f3 int, f4 int, f5 int, f6 int, f7 int, f8 int);
+insert into test8(f1, f8) values (x'f1'::int, 0);
+select t_bits, t_data from heap_page_items(get_raw_page('test8', 0));
+ t_bits | t_data
+----------+--------------------
+ 10000001 | \xf100000000000000
+(1 row)
+
+select tuple_data_split('test8'::regclass, t_data, t_infomask, t_infomask2, t_bits)
+ from heap_page_items(get_raw_page('test8', 0));
+ tuple_data_split
+-------------------------------------------------------------
+ {"\\xf1000000",NULL,NULL,NULL,NULL,NULL,NULL,"\\x00000000"}
+(1 row)
+
+drop table test8;
diff --git a/contrib/pageinspect/heapfuncs.c b/contrib/pageinspect/heapfuncs.c
index 088254453e..99f409846c 100644
--- a/contrib/pageinspect/heapfuncs.c
+++ b/contrib/pageinspect/heapfuncs.c
@@ -234,7 +234,7 @@ heap_page_items(PG_FUNCTION_ARGS)
int bits_len;
bits_len =
- ((tuphdr->t_infomask2 & HEAP_NATTS_MASK) / 8 + 1) * 8;
+ BITMAPLEN(HeapTupleHeaderGetNatts(tuphdr)) * BITS_PER_BYTE;
values[11] = CStringGetTextDatum(
bits_to_text(tuphdr->t_bits, bits_len));
}
@@ -436,12 +436,12 @@ tuple_data_split(PG_FUNCTION_ARGS)
int bits_str_len;
int bits_len;
- bits_len = (t_infomask2 & HEAP_NATTS_MASK) / 8 + 1;
+ bits_len = BITMAPLEN(t_infomask2 & HEAP_NATTS_MASK) * BITS_PER_BYTE;
if (!t_bits_str)
ereport(ERROR,
(errcode(ERRCODE_DATA_CORRUPTED),
errmsg("argument of t_bits is null, but it is expected to be null and %d character long",
- bits_len * 8)));
+ bits_len)));
bits_str_len = strlen(t_bits_str);
if ((bits_str_len % 8) != 0)
@@ -449,11 +449,11 @@ tuple_data_split(PG_FUNCTION_ARGS)
(errcode(ERRCODE_DATA_CORRUPTED),
errmsg("length of t_bits is not a multiple of eight")));
- if (bits_len * 8 != bits_str_len)
+ if (bits_len != bits_str_len)
ereport(ERROR,
(errcode(ERRCODE_DATA_CORRUPTED),
errmsg("unexpected length of t_bits %u, expected %d",
- bits_str_len, bits_len * 8)));
+ bits_str_len, bits_len)));
/* do the conversion */
t_bits = text_to_bits(t_bits_str, bits_str_len);
diff --git a/contrib/pageinspect/sql/page.sql b/contrib/pageinspect/sql/page.sql
index 493ca9b211..16b4571fbf 100644
--- a/contrib/pageinspect/sql/page.sql
+++ b/contrib/pageinspect/sql/page.sql
@@ -41,3 +41,11 @@ select get_raw_page('test_partitioned', 0); -- error about partitioned table
create table test_part1 partition of test_partitioned for values from ( 1 ) to (100);
select get_raw_page('test_part1', 0); -- get farther and error about empty table
drop table test_partitioned;
+
+-- check null bitmap alignment for table whose the number of attributes is multiple of 8
+create table test8 (f1 int, f2 int, f3 int, f4 int, f5 int, f6 int, f7 int, f8 int);
+insert into test8(f1, f8) values (x'f1'::int, 0);
+select t_bits, t_data from heap_page_items(get_raw_page('test8', 0));
+select tuple_data_split('test8'::regclass, t_data, t_infomask, t_infomask2, t_bits)
+ from heap_page_items(get_raw_page('test8', 0));
+drop table test8;
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Message-ID: <da8b621a-ebbd-4fe6-c436-130cc8beb0a0@gmail.com>
Permalink: ../da8b621a-ebbd-4fe6-c436-130cc8beb0a0@gmail.com/
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To: pgsql-hackers@postgresql.org
Cc: milyutinma@gmail.com, x4mmm@yandex-team.ru
Subject: Re: [HACKERS] wrong t_bits alignment in pageinspect
In-Reply-To: <da8b621a-ebbd-4fe6-c436-130cc8beb0a0@gmail.com>
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