From 7a40ea2138102545848ea86a361f1b8dec7552b5 Mon Sep 17 00:00:00 2001 From: Bram Moolenaar Date: Sun, 22 Jan 2017 18:34:57 +0100 Subject: patch 8.0.0219: ubsan reports errors for overflow Problem: Ubsan reports errors for integer overflow. Solution: Define macros for minimum and maximum values. Select an expression based on the value. (Mike Williams) --- src/charset.c | 36 +++++++++++++++++++++++++++++++----- 1 file changed, 31 insertions(+), 5 deletions(-) (limited to 'src/charset.c') diff --git a/src/charset.c b/src/charset.c index c3b62590bc..c047afec7f 100644 --- a/src/charset.c +++ b/src/charset.c @@ -1901,7 +1901,11 @@ vim_str2nr( n += 2; /* skip over "0b" */ while ('0' <= *ptr && *ptr <= '1') { - un = 2 * un + (unsigned long)(*ptr - '0'); + /* avoid ubsan error for overflow */ + if (un < UVARNUM_MAX / 2) + un = 2 * un + (unsigned long)(*ptr - '0'); + else + un = UVARNUM_MAX; ++ptr; if (n++ == maxlen) break; @@ -1912,7 +1916,11 @@ vim_str2nr( /* octal */ while ('0' <= *ptr && *ptr <= '7') { - un = 8 * un + (uvarnumber_T)(*ptr - '0'); + /* avoid ubsan error for overflow */ + if (un < UVARNUM_MAX / 8) + un = 8 * un + (uvarnumber_T)(*ptr - '0'); + else + un = UVARNUM_MAX; ++ptr; if (n++ == maxlen) break; @@ -1925,7 +1933,11 @@ vim_str2nr( n += 2; /* skip over "0x" */ while (vim_isxdigit(*ptr)) { - un = 16 * un + (uvarnumber_T)hex2nr(*ptr); + /* avoid ubsan error for overflow */ + if (un < UVARNUM_MAX / 16) + un = 16 * un + (uvarnumber_T)hex2nr(*ptr); + else + un = UVARNUM_MAX; ++ptr; if (n++ == maxlen) break; @@ -1936,7 +1948,11 @@ vim_str2nr( /* decimal */ while (VIM_ISDIGIT(*ptr)) { - un = 10 * un + (uvarnumber_T)(*ptr - '0'); + /* avoid ubsan error for overflow */ + if (un < UVARNUM_MAX / 10) + un = 10 * un + (uvarnumber_T)(*ptr - '0'); + else + un = UVARNUM_MAX; ++ptr; if (n++ == maxlen) break; @@ -1950,9 +1966,19 @@ vim_str2nr( if (nptr != NULL) { if (negative) /* account for leading '-' for decimal numbers */ - *nptr = -(varnumber_T)un; + { + /* avoid ubsan error for overflow */ + if (un > VARNUM_MAX) + *nptr = VARNUM_MIN; + else + *nptr = -(varnumber_T)un; + } else + { + if (un > VARNUM_MAX) + un = VARNUM_MAX; *nptr = (varnumber_T)un; + } } if (unptr != NULL) *unptr = un; -- cgit v1.2.3