Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commitf261ad2

Browse files
committed
Fix possible buffer overrun in contrib/pg_trgm.
Allow for the possibility that folding a string to lower case makes itlonger (due to replacing a character with a longer multibyte character).This doesn't change the number of trigrams that will be extracted, butit does affect the required size of an intermediate buffer ingenerate_trgm(). Per bug #8821 from Ufuk Kayserilioglu.Also install some checks that the input string length is not so largeas to cause overflow in the calculations of palloc request sizes.Back-patch to all supported versions.
1 parent6c3f040 commitf261ad2

File tree

1 file changed

+21
-3
lines changed

1 file changed

+21
-3
lines changed

‎contrib/pg_trgm/trgm_op.c‎

Lines changed: 21 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -3,9 +3,10 @@
33
*/
44
#include"trgm.h"
55
#include<ctype.h>
6-
#include"utils/array.h"
76
#include"catalog/pg_type.h"
87
#include"tsearch/ts_locale.h"
8+
#include"utils/array.h"
9+
#include"utils/memutils.h"
910

1011
PG_MODULE_MAGIC;
1112

@@ -172,6 +173,18 @@ generate_trgm(char *str, int slen)
172173
char*bword,
173174
*eword;
174175

176+
/*
177+
* Guard against possible overflow in the palloc requests below. (We
178+
* don't worry about the additive constants, since palloc can detect
179+
* requests that are a little above MaxAllocSize --- we just need to
180+
* prevent integer overflow in the multiplications.)
181+
*/
182+
if ((Size) (slen /2) >= (MaxAllocSize / (sizeof(trgm)*3))||
183+
(Size)slen >= (MaxAllocSize /pg_database_encoding_max_length()))
184+
ereport(ERROR,
185+
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
186+
errmsg("out of memory")));
187+
175188
trg= (TRGM*)palloc(TRGMHDRSIZE+sizeof(trgm)* (slen /2+1)*3);
176189
trg->flag=ARRKEY;
177190
SET_VARSIZE(trg,TRGMHDRSIZE);
@@ -181,7 +194,8 @@ generate_trgm(char *str, int slen)
181194

182195
tptr=GETARR(trg);
183196

184-
buf=palloc(sizeof(char)* (slen+4));
197+
/* Allocate a buffer for case-folded, blank-padded words */
198+
buf= (char*)palloc(slen*pg_database_encoding_max_length()+4);
185199

186200
if (LPADDING>0)
187201
{
@@ -205,6 +219,7 @@ generate_trgm(char *str, int slen)
205219
#ifdefIGNORECASE
206220
pfree(bword);
207221
#endif
222+
208223
buf[LPADDING+bytelen]=' ';
209224
buf[LPADDING+bytelen+1]=' ';
210225

@@ -220,7 +235,10 @@ generate_trgm(char *str, int slen)
220235
if ((len=tptr-GETARR(trg))==0)
221236
returntrg;
222237

223-
if (len>0)
238+
/*
239+
* Make trigrams unique.
240+
*/
241+
if (len>1)
224242
{
225243
qsort((void*)GETARR(trg),len,sizeof(trgm),comp_trgm);
226244
len=unique_array(GETARR(trg),len);

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp