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

Commit9b5e831

Browse files
committed
Check return values of sensitive system library calls.
PostgreSQL already checked the vast majority of these, missing thishandful that nearly cannot fail. If putenv() failed with ENOMEM inpg_GSS_recvauth(), authentication would proceed with the wrong keytabfile. If strftime() returned zero in cache_locale_time(), using theunspecified buffer contents could lead to information exposure or acrash. Back-patch to 9.0 (all supported versions).Other unchecked calls to these functions, especially those in frontendcode, pose negligible security concern. This patch does not addressthem. Nonetheless, it is always better to check return values whosespecification provides for indicating an error.In passing, fix an off-by-one error in strftime_win32()'s invocation ofWideCharToMultiByte(). Upon retrieving a value of exactly MAX_L10N_DATAbytes, strftime_win32() would overrun the caller's buffer by one byte.MAX_L10N_DATA is chosen to exceed the length of every possible value, sothe vulnerable scenario probably does not arise.Security:CVE-2015-3166
1 parentb08c7af commit9b5e831

File tree

2 files changed

+48
-33
lines changed

2 files changed

+48
-33
lines changed

‎src/backend/libpq/auth.c

Lines changed: 4 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -1014,15 +1014,16 @@ pg_GSS_recvauth(Port *port)
10141014
size_tkt_len=strlen(pg_krb_server_keyfile)+14;
10151015
char*kt_path=malloc(kt_len);
10161016

1017-
if (!kt_path)
1017+
if (!kt_path||
1018+
snprintf(kt_path,kt_len,"KRB5_KTNAME=%s",
1019+
pg_krb_server_keyfile)!=kt_len-2||
1020+
putenv(kt_path)!=0)
10181021
{
10191022
ereport(LOG,
10201023
(errcode(ERRCODE_OUT_OF_MEMORY),
10211024
errmsg("out of memory")));
10221025
returnSTATUS_ERROR;
10231026
}
1024-
snprintf(kt_path,kt_len,"KRB5_KTNAME=%s",pg_krb_server_keyfile);
1025-
putenv(kt_path);
10261027
}
10271028
}
10281029

‎src/backend/utils/adt/pg_locale.c

Lines changed: 44 additions & 30 deletions
Original file line numberDiff line numberDiff line change
@@ -558,24 +558,34 @@ PGLC_localeconv(void)
558558
* pg_strftime(), which isn't locale-aware and does not need to be replaced.
559559
*/
560560
staticsize_t
561-
strftime_win32(char*dst,size_tdstlen,constwchar_t*format,conststructtm*tm)
561+
strftime_win32(char*dst,size_tdstlen,
562+
constchar*format,conststructtm*tm)
562563
{
563564
size_tlen;
565+
wchar_twformat[8];/* formats used below need 3 bytes */
564566
wchar_twbuf[MAX_L10N_DATA];
565567
intencoding;
566568

567569
encoding=GetDatabaseEncoding();
568570

569-
len=wcsftime(wbuf,MAX_L10N_DATA,format,tm);
571+
/* get a wchar_t version of the format string */
572+
len=MultiByteToWideChar(CP_UTF8,0,format,-1,
573+
wformat,lengthof(wformat));
574+
if (len==0)
575+
elog(ERROR,"could not convert format string from UTF-8: error code %lu",
576+
GetLastError());
577+
578+
len=wcsftime(wbuf,MAX_L10N_DATA,wformat,tm);
570579
if (len==0)
571580

572581
/*
573-
* strftimecallfailed - return 0 with the contents of dst
574-
* unspecified
582+
* strftime failed, possibly because the result would not fit in
583+
*MAX_L10N_DATA. Return 0 with the contents of dstunspecified.
575584
*/
576585
return0;
577586

578-
len=WideCharToMultiByte(CP_UTF8,0,wbuf,len,dst,dstlen,NULL,NULL);
587+
len=WideCharToMultiByte(CP_UTF8,0,wbuf,len,dst,dstlen-1,
588+
NULL,NULL);
579589
if (len==0)
580590
elog(ERROR,
581591
"could not convert string to UTF-8:error %lu",GetLastError());
@@ -596,9 +606,33 @@ strftime_win32(char *dst, size_t dstlen, const wchar_t *format, const struct tm
596606
}
597607

598608
/* redefine strftime() */
599-
#definestrftime(a,b,c,d) strftime_win32(a,b,L##c,d)
609+
#definestrftime(a,b,c,d) strftime_win32(a,b,c,d)
600610
#endif/* WIN32 */
601611

612+
/* Subroutine for cache_locale_time(). */
613+
staticvoid
614+
cache_single_time(char**dst,constchar*format,conststructtm*tm)
615+
{
616+
charbuf[MAX_L10N_DATA];
617+
char*ptr;
618+
619+
/*
620+
* MAX_L10N_DATA is sufficient buffer space for every known locale, and
621+
* POSIX defines no strftime() errors. (Buffer space exhaustion is not an
622+
* error.) An implementation might report errors (e.g. ENOMEM) by
623+
* returning 0 (or, less plausibly, a negative value) and setting errno.
624+
* Report errno just in case the implementation did that, but clear it in
625+
* advance of the call so we don't emit a stale, unrelated errno.
626+
*/
627+
errno=0;
628+
if (strftime(buf,MAX_L10N_DATA,format,tm) <=0)
629+
elog(ERROR,"strftime(%s) failed: %m",format);
630+
631+
ptr=MemoryContextStrdup(TopMemoryContext,buf);
632+
if (*dst)
633+
pfree(*dst);
634+
*dst=ptr;
635+
}
602636

603637
/*
604638
* Update the lc_time localization cache variables if needed.
@@ -609,8 +643,6 @@ cache_locale_time(void)
609643
char*save_lc_time;
610644
time_ttimenow;
611645
structtm*timeinfo;
612-
charbuf[MAX_L10N_DATA];
613-
char*ptr;
614646
inti;
615647

616648
#ifdefWIN32
@@ -657,35 +689,17 @@ cache_locale_time(void)
657689
for (i=0;i<7;i++)
658690
{
659691
timeinfo->tm_wday=i;
660-
strftime(buf,MAX_L10N_DATA,"%a",timeinfo);
661-
ptr=MemoryContextStrdup(TopMemoryContext,buf);
662-
if (localized_abbrev_days[i])
663-
pfree(localized_abbrev_days[i]);
664-
localized_abbrev_days[i]=ptr;
665-
666-
strftime(buf,MAX_L10N_DATA,"%A",timeinfo);
667-
ptr=MemoryContextStrdup(TopMemoryContext,buf);
668-
if (localized_full_days[i])
669-
pfree(localized_full_days[i]);
670-
localized_full_days[i]=ptr;
692+
cache_single_time(&localized_abbrev_days[i],"%a",timeinfo);
693+
cache_single_time(&localized_full_days[i],"%A",timeinfo);
671694
}
672695

673696
/* localized months */
674697
for (i=0;i<12;i++)
675698
{
676699
timeinfo->tm_mon=i;
677700
timeinfo->tm_mday=1;/* make sure we don't have invalid date */
678-
strftime(buf,MAX_L10N_DATA,"%b",timeinfo);
679-
ptr=MemoryContextStrdup(TopMemoryContext,buf);
680-
if (localized_abbrev_months[i])
681-
pfree(localized_abbrev_months[i]);
682-
localized_abbrev_months[i]=ptr;
683-
684-
strftime(buf,MAX_L10N_DATA,"%B",timeinfo);
685-
ptr=MemoryContextStrdup(TopMemoryContext,buf);
686-
if (localized_full_months[i])
687-
pfree(localized_full_months[i]);
688-
localized_full_months[i]=ptr;
701+
cache_single_time(&localized_abbrev_months[i],"%b",timeinfo);
702+
cache_single_time(&localized_full_months[i],"%B",timeinfo);
689703
}
690704

691705
/* try to restore internal settings */

0 commit comments

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