diff options
| -rw-r--r-- | disk-utils/mkswap.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/disk-utils/mkswap.c b/disk-utils/mkswap.c index c19993752..bc6c1d291 100644 --- a/disk-utils/mkswap.c +++ b/disk-utils/mkswap.c @@ -559,13 +559,18 @@ main(int argc, char ** argv) { usage(); } if (block_count) { - /* this silly user specified the number of blocks - explicitly */ - char *tmp; - int blocks_per_page = pagesize/1024; - PAGES = strtoull(block_count,&tmp,0)/blocks_per_page; - if (*tmp) + /* this silly user specified the number of blocks explicitly */ + char *tmp = NULL; + long long blks; + + errno = 0; + blks = strtoll(block_count, &tmp, 0); + if ((tmp && *tmp) || + (errno != 0 && (blks == ULLONG_MAX || blks == 0)) || + blks < 0) usage(); + + PAGES = blks / (pagesize / 1024); } sz = get_size(device_name); if (!PAGES) { |