postgres.git / summary / log / commit / refs
commit 3531365de5e868224c70cd568384f453056f7646
Author: Tom Lane <tgl@sss.pgh.pa.us>
Date: Wed Aug 15 20:29:32 2018 +0000
First released in: 12.0, 9.3.25, 9.4.20, 9.5.15, 9.6.11, 10.6, 11.0
Clean up assorted misuses of snprintf()'s result value.
Fix a small number of places that were testing the result of snprintf()
but doing so incorrectly. The right test for buffer overrun, per C99,
is "result >= bufsize" not "result > bufsize". Some places were also
checking for failure with "result == -1", but the standard only says
that a negative value is delivered on failure.
(Note that this only makes these places correct if snprintf() delivers
C99-compliant results. But at least now these places are consistent
with all the other places where we assume that.)
Also, make psql_start_test() and isolation_start_test() check for
buffer overrun while constructing their shell commands. There seems
like a higher risk of overrun, with more severe consequences, here
than there is for the individual file paths that are made elsewhere
in the same functions, so this seemed like a worthwhile change.
Also fix guc.c's do_serialize() to initialize errno = 0 before
calling vsnprintf. In principle, this should be unnecessary because
vsnprintf should have set errno if it returns a failure indication ...
but the other two places this coding pattern is cribbed from don't
assume that, so let's be consistent.
These errors are all very old, so back-patch as appropriate. I think
that only the shell command overrun cases are even theoretically
reachable in practice, but there's not much point in erroneous error
checks.
Discussion: https://postgr.es/m/17245.1534289329@sss.pgh.pa.us
src/backend/libpq/ip.c | 6 +++---
src/backend/postmaster/pgstat.c | 2 +-
src/interfaces/ecpg/pgtypeslib/common.c | 2 +-
src/port/getaddrinfo.c | 2 +-
src/test/isolation/isolation_main.c | 22 +++++++++++++++++-----
src/test/regress/pg_regress.c | 2 +-
src/test/regress/pg_regress_main.c | 26 +++++++++++++++++++-------
7 files changed, 43 insertions(+), 19 deletions(-)
diff --git a/src/backend/libpq/ip.c b/src/backend/libpq/ip.c
index 9c3e85bbf7f..b6499529c75 100644
--- a/src/backend/libpq/ip.c
+++ b/src/backend/libpq/ip.c
@@ -240,7 +240,7 @@ getnameinfo_unix(const struct sockaddr_un * sa, int salen,
char *service, int servicelen,
int flags)
{
- int ret = -1;
+ int ret;
/* Invalid arguments. */
if (sa == NULL || sa->sun_family != AF_UNIX ||
@@ -250,14 +250,14 @@ getnameinfo_unix(const struct sockaddr_un * sa, int salen,
if (node)
{
ret = snprintf(node, nodelen, "%s", "[local]");
- if (ret == -1 || ret > nodelen)
+ if (ret < 0 || ret >= nodelen)
return EAI_MEMORY;
}
if (service)
{
ret = snprintf(service, servicelen, "%s", sa->sun_path);
- if (ret == -1 || ret > servicelen)
+ if (ret < 0 || ret >= servicelen)
return EAI_MEMORY;
}
diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c
index e872bf6a313..8a2b69bad45 100644
--- a/src/backend/postmaster/pgstat.c
+++ b/src/backend/postmaster/pgstat.c
@@ -3676,7 +3676,7 @@ get_dbstat_filename(bool permanent, bool tempname, Oid databaseid,
pgstat_stat_directory,
databaseid,
tempname ? "tmp" : "stat");
- if (printed > len)
+ if (printed >= len)
elog(ERROR, "overlength pgstat path");
}
diff --git a/src/interfaces/ecpg/pgtypeslib/common.c b/src/interfaces/ecpg/pgtypeslib/common.c
index 7adca66618d..998764d6627 100644
--- a/src/interfaces/ecpg/pgtypeslib/common.c
+++ b/src/interfaces/ecpg/pgtypeslib/common.c
@@ -110,7 +110,7 @@ pgtypes_fmt_replace(union un_fmt_comb replace_val, int replace_type, char **outp
break;
}
- if (i < 0)
+ if (i < 0 || i >= PGTYPES_FMT_NUM_MAX_DIGITS)
{
free(t);
return -1;
diff --git a/src/port/getaddrinfo.c b/src/port/getaddrinfo.c
index a35354e3728..45cfe558529 100644
--- a/src/port/getaddrinfo.c
+++ b/src/port/getaddrinfo.c
@@ -404,7 +404,7 @@ getnameinfo(const struct sockaddr * sa, int salen,
ret = snprintf(service, servicelen, "%d",
ntohs(((struct sockaddr_in *) sa)->sin_port));
}
- if (ret == -1 || ret >= servicelen)
+ if (ret < 0 || ret >= servicelen)
return EAI_MEMORY;
}
diff --git a/src/test/isolation/isolation_main.c b/src/test/isolation/isolation_main.c
index 48a0e1235a2..f692c2f8dc9 100644
--- a/src/test/isolation/isolation_main.c
+++ b/src/test/isolation/isolation_main.c
@@ -54,14 +54,26 @@ isolation_start_test(const char *testname,
add_stringlist_item(expectfiles, expectfile);
if (launcher)
+ {
offset += snprintf(psql_cmd + offset, sizeof(psql_cmd) - offset,
"%s ", launcher);
+ if (offset >= sizeof(psql_cmd))
+ {
+ fprintf(stderr, _("command too long\n"));
+ exit(2);
+ }
+ }
- snprintf(psql_cmd + offset, sizeof(psql_cmd) - offset,
- SYSTEMQUOTE "\"./isolationtester\" \"dbname=%s\" < \"%s\" > \"%s\" 2>&1" SYSTEMQUOTE,
- dblist->str,
- infile,
- outfile);
+ offset += snprintf(psql_cmd + offset, sizeof(psql_cmd) - offset,
+ SYSTEMQUOTE "\"./isolationtester\" \"dbname=%s\" < \"%s\" > \"%s\" 2>&1" SYSTEMQUOTE,
+ dblist->str,
+ infile,
+ outfile);
+ if (offset >= sizeof(psql_cmd))
+ {
+ fprintf(stderr, _("command too long\n"));
+ exit(2);
+ }
pid = spawn_process(psql_cmd);
diff --git a/src/test/regress/pg_regress.c b/src/test/regress/pg_regress.c
index f1111d92476..a074433ede2 100644
--- a/src/test/regress/pg_regress.c
+++ b/src/test/regress/pg_regress.c
@@ -1102,7 +1102,7 @@ config_sspi_auth(const char *pgdata)
} while (0)
res = snprintf(fname, sizeof(fname), "%s/pg_hba.conf", pgdata);
- if (res < 0 || res >= sizeof(fname) - 1)
+ if (res < 0 || res >= sizeof(fname))
{
/*
* Truncating this name is a fatal error, because we must not fail to
diff --git a/src/test/regress/pg_regress_main.c b/src/test/regress/pg_regress_main.c
index f13e27ff2bc..c6758e32412 100644
--- a/src/test/regress/pg_regress_main.c
+++ b/src/test/regress/pg_regress_main.c
@@ -60,16 +60,28 @@ psql_start_test(const char *testname,
add_stringlist_item(expectfiles, expectfile);
if (launcher)
+ {
offset += snprintf(psql_cmd + offset, sizeof(psql_cmd) - offset,
"%s ", launcher);
+ if (offset >= sizeof(psql_cmd))
+ {
+ fprintf(stderr, _("command too long\n"));
+ exit(2);
+ }
+ }
- snprintf(psql_cmd + offset, sizeof(psql_cmd) - offset,
- SYSTEMQUOTE "\"%s%spsql\" -X -a -q -d \"%s\" < \"%s\" > \"%s\" 2>&1" SYSTEMQUOTE,
- psqldir ? psqldir : "",
- psqldir ? "/" : "",
- dblist->str,
- infile,
- outfile);
+ offset += snprintf(psql_cmd + offset, sizeof(psql_cmd) - offset,
+ SYSTEMQUOTE "\"%s%spsql\" -X -a -q -d \"%s\" < \"%s\" > \"%s\" 2>&1" SYSTEMQUOTE,
+ psqldir ? psqldir : "",
+ psqldir ? "/" : "",
+ dblist->str,
+ infile,
+ outfile);
+ if (offset >= sizeof(psql_cmd))
+ {
+ fprintf(stderr, _("command too long\n"));
+ exit(2);
+ }
pid = spawn_process(psql_cmd);
[parent: 235eab04ec01]