diff options
| author | Dominique Pelle <dominique.pelle@gmail.com> | 2022-10-12 13:30:25 +0100 |
|---|---|---|
| committer | Bram Moolenaar <Bram@vim.org> | 2022-10-12 13:30:25 +0100 |
| commit | 84d14ccdb50dc9f362066a2c83bfaf331314e5ea (patch) | |
| tree | 7c89abcc26b741f738414e43f31b423bf4e7721e | |
| parent | d987642626f84fe2f0b32a1ca5ede31b436ce677 (diff) | |
patch 9.0.0733: use of strftime() is not safev9.0.0733
Problem: Use of strftime() is not safe.
Solution: Check the return value of strftime(). Use a larger buffer and
correctly pass the available space. (Dominique Pellé, closes
#11348)
| -rw-r--r-- | src/time.c | 31 | ||||
| -rw-r--r-- | src/version.c | 2 |
2 files changed, 22 insertions, 11 deletions
diff --git a/src/time.c b/src/time.c index f8e8c5afe2..a5be297d39 100644 --- a/src/time.c +++ b/src/time.c @@ -82,7 +82,7 @@ vim_time(void) char * get_ctime(time_t thetime, int add_newline) { - static char buf[50]; + static char buf[100]; // hopefully enough for every language #ifdef HAVE_STRFTIME struct tm tmval; struct tm *curtime; @@ -90,12 +90,20 @@ get_ctime(time_t thetime, int add_newline) curtime = vim_localtime(&thetime, &tmval); // MSVC returns NULL for an invalid value of seconds. if (curtime == NULL) - vim_strncpy((char_u *)buf, (char_u *)_("(Invalid)"), sizeof(buf) - 1); + vim_strncpy((char_u *)buf, (char_u *)_("(Invalid)"), sizeof(buf) - 2); else { // xgettext:no-c-format - (void)strftime(buf, sizeof(buf) - 1, _("%a %b %d %H:%M:%S %Y"), - curtime); + if (strftime(buf, sizeof(buf) - 2, _("%a %b %d %H:%M:%S %Y"), curtime) + == 0) + { + // Quoting "man strftime": + // > If the length of the result string (including the terminating + // > null byte) would exceed max bytes, then strftime() returns 0, + // > and the contents of the array are undefined. + vim_strncpy((char_u *)buf, (char_u *)_("(Invalid)"), + sizeof(buf) - 2); + } # ifdef MSWIN if (enc_codepage >= 0 && (int)GetACP() != enc_codepage) { @@ -105,7 +113,7 @@ get_ctime(time_t thetime, int add_newline) acp_to_enc((char_u *)buf, (int)strlen(buf), &to_free, &len); if (to_free != NULL) { - STRCPY(buf, to_free); + STRNCPY(buf, to_free, sizeof(buf) - 2); vim_free(to_free); } } @@ -318,10 +326,8 @@ f_strftime(typval_T *argvars, typval_T *rettv) convert_setup(&conv, p_enc, enc); if (conv.vc_type != CONV_NONE) p = string_convert(&conv, p, NULL); - if (p != NULL) - (void)strftime((char *)result_buf, sizeof(result_buf), - (char *)p, curtime); - else + if (p == NULL || strftime((char *)result_buf, sizeof(result_buf), + (char *)p, curtime) == 0) result_buf[0] = NUL; if (conv.vc_type != CONV_NONE) @@ -1117,16 +1123,19 @@ add_time(char_u *buf, size_t buflen, time_t tt) #ifdef HAVE_STRFTIME struct tm tmval; struct tm *curtime; + int n; if (vim_time() - tt >= 100) { curtime = vim_localtime(&tt, &tmval); if (vim_time() - tt < (60L * 60L * 12L)) // within 12 hours - (void)strftime((char *)buf, buflen, "%H:%M:%S", curtime); + n = strftime((char *)buf, buflen, "%H:%M:%S", curtime); else // longer ago - (void)strftime((char *)buf, buflen, "%Y/%m/%d %H:%M:%S", curtime); + n = strftime((char *)buf, buflen, "%Y/%m/%d %H:%M:%S", curtime); + if (n == 0) + buf[0] = NUL; } else #endif diff --git a/src/version.c b/src/version.c index 37d64fbfb7..eeb1579ef2 100644 --- a/src/version.c +++ b/src/version.c @@ -700,6 +700,8 @@ static char *(features[]) = static int included_patches[] = { /* Add new patch number below this line */ /**/ + 733, +/**/ 732, /**/ 731, |