From: Tom Lane Date: Mon, 17 Feb 2014 16:20:35 +0000 (-0500) Subject: Prevent potential overruns of fixed-size buffers. X-Git-Tag: REL9_0_16~3 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=45bf2404a2f586a35e8647890a7d5917b787a623;p=postgresql Prevent potential overruns of fixed-size buffers. Coverity identified a number of places in which it couldn't prove that a string being copied into a fixed-size buffer would fit. We believe that most, perhaps all of these are in fact safe, or are copying data that is coming from a trusted source so that any overrun is not really a security issue. Nonetheless it seems prudent to forestall any risk by using strlcpy() and similar functions. Fixes by Peter Eisentraut and Jozef Mlich based on Coverity reports. In addition, fix a potential null-pointer-dereference crash in contrib/chkpass. The crypt(3) function is defined to return NULL on failure, but chkpass.c didn't check for that before using the result. The main practical case in which this could be an issue is if libc is configured to refuse to execute unapproved hashing algorithms (e.g., "FIPS mode"). This ideally should've been a separate commit, but since it touches code adjacent to one of the buffer overrun changes, I included it in this commit to avoid last-minute merge issues. This issue was reported by Honza Horak. Security: CVE-2014-0065 for buffer overruns, CVE-2014-0066 for crypt() --- diff --git a/contrib/chkpass/chkpass.c b/contrib/chkpass/chkpass.c index 56a998ec83..b54aacca52 100644 --- a/contrib/chkpass/chkpass.c +++ b/contrib/chkpass/chkpass.c @@ -70,6 +70,7 @@ chkpass_in(PG_FUNCTION_ARGS) char *str = PG_GETARG_CSTRING(0); chkpass *result; char mysalt[4]; + char *crypt_output; static char salt_chars[] = "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; @@ -92,7 +93,15 @@ chkpass_in(PG_FUNCTION_ARGS) mysalt[1] = salt_chars[random() & 0x3f]; mysalt[2] = 0; /* technically the terminator is not necessary * but I like to play safe */ - strcpy(result->password, crypt(str, mysalt)); + + crypt_output = crypt(str, mysalt); + if (crypt_output == NULL) + ereport(ERROR, + (errcode(ERRCODE_INVALID_PARAMETER_VALUE), + errmsg("crypt() failed"))); + + strlcpy(result->password, crypt_output, sizeof(result->password)); + PG_RETURN_POINTER(result); } @@ -141,9 +150,16 @@ chkpass_eq(PG_FUNCTION_ARGS) chkpass *a1 = (chkpass *) PG_GETARG_POINTER(0); text *a2 = PG_GETARG_TEXT_PP(1); char str[9]; + char *crypt_output; text_to_cstring_buffer(a2, str, sizeof(str)); - PG_RETURN_BOOL(strcmp(a1->password, crypt(str, a1->password)) == 0); + crypt_output = crypt(str, a1->password); + if (crypt_output == NULL) + ereport(ERROR, + (errcode(ERRCODE_INVALID_PARAMETER_VALUE), + errmsg("crypt() failed"))); + + PG_RETURN_BOOL(strcmp(a1->password, crypt_output) == 0); } PG_FUNCTION_INFO_V1(chkpass_ne); @@ -153,7 +169,14 @@ chkpass_ne(PG_FUNCTION_ARGS) chkpass *a1 = (chkpass *) PG_GETARG_POINTER(0); text *a2 = PG_GETARG_TEXT_PP(1); char str[9]; + char *crypt_output; text_to_cstring_buffer(a2, str, sizeof(str)); - PG_RETURN_BOOL(strcmp(a1->password, crypt(str, a1->password)) != 0); + crypt_output = crypt(str, a1->password); + if (crypt_output == NULL) + ereport(ERROR, + (errcode(ERRCODE_INVALID_PARAMETER_VALUE), + errmsg("crypt() failed"))); + + PG_RETURN_BOOL(strcmp(a1->password, crypt_output) != 0); } diff --git a/contrib/pg_standby/pg_standby.c b/contrib/pg_standby/pg_standby.c index 70680e762d..adfbad5f38 100644 --- a/contrib/pg_standby/pg_standby.c +++ b/contrib/pg_standby/pg_standby.c @@ -337,7 +337,7 @@ SetWALFileNameForCleanup(void) if (strcmp(restartWALFileName, nextWALFileName) > 0) return false; - strcpy(exclusiveCleanupFileName, restartWALFileName); + strlcpy(exclusiveCleanupFileName, restartWALFileName, sizeof(exclusiveCleanupFileName)); return true; } diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index 7424201c43..20bcdcd401 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -5860,7 +5860,7 @@ StartupXLOG(void) * see them */ XLogCtl->RecoveryTargetTLI = recoveryTargetTLI; - strncpy(XLogCtl->archiveCleanupCommand, + strlcpy(XLogCtl->archiveCleanupCommand, archiveCleanupCommand ? archiveCleanupCommand : "", sizeof(XLogCtl->archiveCleanupCommand)); diff --git a/src/backend/tsearch/spell.c b/src/backend/tsearch/spell.c index cbfd386074..561ea399d7 100644 --- a/src/backend/tsearch/spell.c +++ b/src/backend/tsearch/spell.c @@ -181,7 +181,7 @@ NIAddSpell(IspellDict *Conf, const char *word, const char *flag) } Conf->Spell[Conf->nspell] = (SPELL *) tmpalloc(SPELLHDRSZ + strlen(word) + 1); strcpy(Conf->Spell[Conf->nspell]->word, word); - strncpy(Conf->Spell[Conf->nspell]->p.flag, flag, MAXFLAGLEN); + strlcpy(Conf->Spell[Conf->nspell]->p.flag, flag, MAXFLAGLEN); Conf->nspell++; } diff --git a/src/backend/utils/adt/datetime.c b/src/backend/utils/adt/datetime.c index 95d4556c73..fb9a95a1bd 100644 --- a/src/backend/utils/adt/datetime.c +++ b/src/backend/utils/adt/datetime.c @@ -89,10 +89,10 @@ char *days[] = {"Sunday", "Monday", "Tuesday", "Wednesday", * Note that this table must be strictly alphabetically ordered to allow an * O(ln(N)) search algorithm to be used. * - * The text field is NOT guaranteed to be NULL-terminated. + * The token field is NOT guaranteed to be NULL-terminated. * - * To keep this table reasonably small, we divide the lexval for TZ and DTZ - * entries by 15 (so they are on 15 minute boundaries) and truncate the text + * To keep this table reasonably small, we divide the value for TZ and DTZ + * entries by 15 (so they are on 15 minute boundaries) and truncate the token * field at TOKMAXLEN characters. * Formerly, we divided by 10 rather than 15 but there are a few time zones * which are 30 or 45 minutes away from an even hour, most are on an hour @@ -107,7 +107,7 @@ static datetkn *timezonetktbl = NULL; static int sztimezonetktbl = 0; static const datetkn datetktbl[] = { -/* text, token, lexval */ + /* token, type, value */ {EARLY, RESERV, DTK_EARLY}, /* "-infinity" reserved for "early time" */ {DA_D, ADBC, AD}, /* "ad" for years > 0 */ {"allballs", RESERV, DTK_ZULU}, /* 00:00:00 */ @@ -187,7 +187,7 @@ static const datetkn datetktbl[] = { static int szdatetktbl = sizeof datetktbl / sizeof datetktbl[0]; static datetkn deltatktbl[] = { - /* text, token, lexval */ + /* token, type, value */ {"@", IGNORE_DTF, 0}, /* postgres relative prefix */ {DAGO, AGO, 0}, /* "ago" indicates negative time offset */ {"c", UNITS, DTK_CENTURY}, /* "century" relative */ @@ -4152,6 +4152,7 @@ InstallTimeZoneAbbrevs(tzEntry *abbrevs, int n) n * sizeof(datetkn)); for (i = 0; i < n; i++) { + /* do NOT use strlcpy here; token field need not be null-terminated */ strncpy(newtbl[i].token, abbrevs[i].abbrev, TOKMAXLEN); newtbl[i].type = abbrevs[i].is_dst ? DTZ : TZ; TOVAL(&newtbl[i], abbrevs[i].offset / 60); diff --git a/src/bin/initdb/initdb.c b/src/bin/initdb/initdb.c index f3e1d90dc4..901aed9678 100644 --- a/src/bin/initdb/initdb.c +++ b/src/bin/initdb/initdb.c @@ -3130,7 +3130,7 @@ main(int argc, char *argv[]) fprintf(stderr, "%s", authwarning); /* Get directory specification used to start this executable */ - strcpy(bin_dir, argv[0]); + strlcpy(bin_dir, argv[0], sizeof(bin_dir)); get_parent_directory(bin_dir); printf(_("\nSuccess. You can now start the database server using:\n\n" diff --git a/src/interfaces/ecpg/preproc/pgc.l b/src/interfaces/ecpg/preproc/pgc.l index c7d297a12a..bc16cc5b7f 100644 --- a/src/interfaces/ecpg/preproc/pgc.l +++ b/src/interfaces/ecpg/preproc/pgc.l @@ -1312,7 +1312,7 @@ parse_include(void) yytext[i] = '\0'; memmove(yytext, yytext+1, strlen(yytext)); - strncpy(inc_file, yytext, sizeof(inc_file)); + strlcpy(inc_file, yytext, sizeof(inc_file)); yyin = fopen(inc_file, "r"); if (!yyin) { diff --git a/src/interfaces/libpq/fe-protocol2.c b/src/interfaces/libpq/fe-protocol2.c index 0b3bd3b9aa..66124641ed 100644 --- a/src/interfaces/libpq/fe-protocol2.c +++ b/src/interfaces/libpq/fe-protocol2.c @@ -440,7 +440,7 @@ pqParseInput2(PGconn *conn) if (!conn->result) return; } - strncpy(conn->result->cmdStatus, conn->workBuffer.data, + strlcpy(conn->result->cmdStatus, conn->workBuffer.data, CMDSTATUS_LEN); checkXactStatus(conn, conn->workBuffer.data); conn->asyncStatus = PGASYNC_READY; diff --git a/src/interfaces/libpq/fe-protocol3.c b/src/interfaces/libpq/fe-protocol3.c index 28318f0069..0c484824e6 100644 --- a/src/interfaces/libpq/fe-protocol3.c +++ b/src/interfaces/libpq/fe-protocol3.c @@ -206,7 +206,7 @@ pqParseInput3(PGconn *conn) if (!conn->result) return; } - strncpy(conn->result->cmdStatus, conn->workBuffer.data, + strlcpy(conn->result->cmdStatus, conn->workBuffer.data, CMDSTATUS_LEN); conn->asyncStatus = PGASYNC_READY; break; diff --git a/src/port/exec.c b/src/port/exec.c index 5dd5963f2c..1ef2b11c03 100644 --- a/src/port/exec.c +++ b/src/port/exec.c @@ -66,7 +66,7 @@ validate_exec(const char *path) if (strlen(path) >= strlen(".exe") && pg_strcasecmp(path + strlen(path) - strlen(".exe"), ".exe") != 0) { - strcpy(path_exe, path); + strlcpy(path_exe, path, sizeof(path_exe) - 4); strcat(path_exe, ".exe"); path = path_exe; } @@ -275,7 +275,7 @@ resolve_symlinks(char *path) } /* must copy final component out of 'path' temporarily */ - strcpy(link_buf, fname); + strlcpy(link_buf, fname, sizeof(link_buf)); if (!getcwd(path, MAXPGPATH)) { diff --git a/src/test/regress/pg_regress.c b/src/test/regress/pg_regress.c index 43edf1ea4b..4509f213a7 100644 --- a/src/test/regress/pg_regress.c +++ b/src/test/regress/pg_regress.c @@ -1237,7 +1237,7 @@ results_differ(const char *testname, const char *resultsfile, const char *defaul */ platform_expectfile = get_expectfile(testname, resultsfile); - strcpy(expectfile, default_expectfile); + strlcpy(expectfile, default_expectfile, sizeof(expectfile)); if (platform_expectfile) { /* @@ -1292,7 +1292,7 @@ results_differ(const char *testname, const char *resultsfile, const char *defaul { /* This diff was a better match than the last one */ best_line_count = l; - strcpy(best_expect_file, alt_expectfile); + strlcpy(best_expect_file, alt_expectfile, sizeof(best_expect_file)); } free(alt_expectfile); } @@ -1320,7 +1320,7 @@ results_differ(const char *testname, const char *resultsfile, const char *defaul { /* This diff was a better match than the last one */ best_line_count = l; - strcpy(best_expect_file, default_expectfile); + strlcpy(best_expect_file, default_expectfile, sizeof(best_expect_file)); } } diff --git a/src/timezone/pgtz.c b/src/timezone/pgtz.c index 13e3bf1944..e286c1178c 100644 --- a/src/timezone/pgtz.c +++ b/src/timezone/pgtz.c @@ -94,7 +94,7 @@ pg_open_tzfile(const char *name, char *canonname) * Loop to split the given name into directory levels; for each level, * search using scan_directory_ci(). */ - strcpy(fullname, pg_TZDIR()); + strlcpy(fullname, pg_TZDIR(), sizeof(fullname)); orignamelen = fullnamelen = strlen(fullname); fname = name; for (;;) @@ -428,7 +428,7 @@ identify_system_timezone(void) } /* Search for the best-matching timezone file */ - strcpy(tmptzdir, pg_TZDIR()); + strlcpy(tmptzdir, pg_TZDIR(), sizeof(tmptzdir)); bestscore = -1; resultbuf[0] = '\0'; scan_available_timezones(tmptzdir, tmptzdir + strlen(tmptzdir) + 1,