diff --git a/include/ssp/stdio.h b/include/ssp/stdio.h --- a/include/ssp/stdio.h +++ b/include/ssp/stdio.h @@ -36,6 +36,10 @@ #include +#if __SSP_FORTIFY_LEVEL > 0 && __EXT1_VISIBLE +#include +#endif + __BEGIN_DECLS #if __SSP_FORTIFY_LEVEL > 0 #if __POSIX_VISIBLE @@ -51,7 +55,31 @@ __ssp_redirect(size_t, fread_unlocked, (void *__restrict __buf, size_t __len, size_t __nmemb, FILE *__restrict __fp), (__buf, __len, __nmemb, __fp)); #if __EXT1_VISIBLE -__ssp_redirect(char *, gets_s, (char *__buf, rsize_t __len), (__buf, __len)); +__ssp_redirect_raw_impl(char *, gets_s, gets_s, + (char *buf, rsize_t len)) +{ + char *retbuf; + size_t bufsz; + int need_fail = 0; + + /* + * If we would have overwritten our buffer, we want to fail the check + * only if these arguments wouldn't have triggered a constraint + * violation. + */ + bufsz = __ssp_bos(buf); + if (bufsz != (size_t)-1 && (size_t)len > bufsz) { + if (len <= RSIZE_MAX) + __chk_fail(); + need_fail = 1; + } + + retbuf = __ssp_real(gets_s)(buf, len); + if (need_fail && retbuf != NULL) + __chk_fail(); + return (retbuf); +} + #endif /* __EXT1_VISIBLE */ __ssp_redirect_raw(char *, tmpnam, tmpnam, (char *__buf), (__buf), 1, __ssp_bos, L_tmpnam);