[PATCH 0/2] MR10785: msvcrt: Only reject negative timestamps with EINVAL in ctime_s

[Hendrik Borchardt (＠hborchardt)]

0 needs to be an allowed value, and negative values should not halt the program but just return EINVAL.

This behavior has been observed with the following python script:

```python
import ctypes

ucrt = ctypes.CDLL("ucrtbase.dll")
buf = ctypes.create_string_buffer(26)

for i in [1, 0, -1]:
    print(f"_ctime64_s for time {i}:")
    t = ctypes.c_int64(i)
    err = ucrt._ctime64_s(buf, ctypes.c_size_t(26), ctypes.byref(t))
    if err == 0:
        print(buf.value.decode())
    else:
        print(f"Error: {err}")

for i in [1, 0, -1]:
    print(f"_ctime32_s for time {i}:")
    t = ctypes.c_int32(i)
    err = ucrt._ctime32_s(buf, ctypes.c_size_t(26), ctypes.byref(t))
    if err == 0:
        print(buf.value.decode())
    else:
        print(f"Error: {err}")

# _ctime64_s for time 1:
# Thu Jan  1 01:00:01 1970
#
# _ctime64_s for time 0:
# Thu Jan  1 01:00:00 1970
#
# _ctime64_s for time -1:
# Error: 22
#
# _ctime32_s for time 1:
# Thu Jan  1 01:00:01 1970
#
# _ctime32_s for time 0:
# Thu Jan  1 01:00:00 1970
#
# _ctime32_s for time -1:
# Error: 22
```

The bug https://bugs.winehq.org/show_bug.cgi?id=57261 is solved by this, because mongodb tries to pretty-print a 0 timestamp, and sets up its own invalid_parameter_handler, which crashes due to NULL arguments.

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/10785

[PATCH 1/2] Test that ctime_s succeeds for timestamp 0

[Hendrik Borchardt]

From: Hendrik Borchardt <[e-mail]>

---
 dlls/msvcrt/tests/time.c | 45 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/dlls/msvcrt/tests/time.c b/dlls/msvcrt/tests/time.c
index aba911f30a4..c72280cccb2 100644
--- a/dlls/msvcrt/tests/time.c
+++ b/dlls/msvcrt/tests/time.c
@@ -51,6 +51,8 @@ typedef struct {
     int refcount;
 } __lc_time_data;
 
+static errno_t    (__cdecl *p_ctime32_s)(char*, size_t, __time32_t*);
+static errno_t    (__cdecl *p_ctime64_s)(char*, size_t, __time64_t*);
 static __time32_t (__cdecl *p_mkgmtime32)(struct tm*);
 static struct tm* (__cdecl *p_gmtime32)(__time32_t*);
 static struct tm* (__cdecl *p_gmtime)(time_t*);
@@ -76,6 +78,8 @@ static void init(void)
     HMODULE hmod = LoadLibraryA("msvcrt.dll");
 
     p_gmtime32 = (void*)GetProcAddress(hmod, "_gmtime32");
+    p_ctime32_s = (void*)GetProcAddress(hmod, "_ctime32_s");
+    p_ctime64_s = (void*)GetProcAddress(hmod, "_ctime64_s");
     p_gmtime = (void*)GetProcAddress(hmod, "gmtime");
     p_gmtime32_s = (void*)GetProcAddress(hmod, "_gmtime32_s");
     p_gmtime64 = (void*)GetProcAddress(hmod, "_gmtime64");
@@ -116,6 +120,45 @@ static void test_ctime(void)
     ret = ctime(&badtime);
     ok(ret == NULL, "expected ctime to return NULL, got %s\n", ret);
 }
+
+static void test_ctime32_s(void)
+{
+    __time32_t goodtime = 0;
+    __time32_t badtime = -1;
+    char out[26];
+    int ret;
+
+    if(!p_ctime32_s) {
+        win_skip("Skipping _ctime32_s tests\n");
+        return;
+    }
+
+    ret = p_ctime32_s(out, 26, &goodtime);
+    ok(ret == 0, "expected _ctime32_s to return NULL, got %i\n", ret);
+
+    ret = p_ctime32_s(out, 26, &badtime);
+    ok(ret == EINVAL, "expected _ctime32_s to return EINVAL, got %i\n", ret);
+}
+
+static void test_ctime64_s(void)
+{
+    __time64_t goodtime = 0;
+    __time64_t badtime = -1;
+    char out[26];
+    int ret;
+
+    if(!p_ctime64_s) {
+        win_skip("Skipping _ctime64_s tests\n");
+        return;
+    }
+
+    ret = p_ctime64_s(out, 26, &goodtime);
+    ok(ret == 0, "expected _ctime64_s to return NULL, got %i\n", ret);
+
+    ret = p_ctime64_s(out, 26, &badtime);
+    ok(ret == EINVAL, "expected _ctime64_s to return EINVAL, got %i\n", ret);
+}
+
 static void test_gmtime(void)
 {
     __time32_t valid, gmt;
@@ -1038,6 +1081,8 @@ START_TEST(time)
     test__tzset();
     test_strftime();
     test_ctime();
+    test_ctime32_s();
+    test_ctime64_s();
     test_gmtime();
     test_gmtime64();
     test_mktime();
-- 
GitLab


https://gitlab.winehq.org/wine/wine/-/merge_requests/10785

[PATCH 2/2] Only reject negative timestamps with EINVAL in ctime_s

[Hendrik Borchardt]

From: Hendrik Borchardt <[e-mail]>

0 needs to be an allowed value, and negative values should not halt the
program but just return EINVAL.
---
 dlls/msvcrt/time.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/dlls/msvcrt/time.c b/dlls/msvcrt/time.c
index b52bb872647..3e826f04bef 100644
--- a/dlls/msvcrt/time.c
+++ b/dlls/msvcrt/time.c
@@ -1737,7 +1737,7 @@ errno_t CDECL _ctime64_s(char *res, size_t len, const __time64_t *time)
     if (!MSVCRT_CHECK_PMT( len >= 26 )) return EINVAL;
     res[0] = '\0';
     if (!MSVCRT_CHECK_PMT( time != NULL )) return EINVAL;
-    if (!MSVCRT_CHECK_PMT( *time > 0 )) return EINVAL;
+    if (*time < 0) return EINVAL;
 
     ret = _localtime64_s( &t, time );
     if (ret)
@@ -1768,7 +1768,7 @@ errno_t CDECL _ctime32_s(char *res, size_t len, const __time32_t *time)
     if (!MSVCRT_CHECK_PMT( len >= 26 )) return EINVAL;
     res[0] = '\0';
     if (!MSVCRT_CHECK_PMT( time != NULL )) return EINVAL;
-    if (!MSVCRT_CHECK_PMT( *time > 0 )) return EINVAL;
+    if (*time < 0) return EINVAL;
 
     ret = _localtime32_s( &t, time );
     if (ret)
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/10785