fallocate: Add range check

Make sure that offset + length does not overflow off_t.

Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>

diff --git a/sys-utils/fallocate.c b/sys-utils/fallocate.c
index 622e0c39c1923904d296519cdc8bdd5503bfef35..ff063fcd5a952b84ca1090cd7c28934fe96b9c21 100644 (file)
--- a/sys-utils/fallocate.c
+++ b/sys-utils/fallocate.c
@@ -479,6 +479,10 @@ int main(int argc, char **argv)
                if (length == 0)
                        errx(EXIT_FAILURE, _("invalid length"));
        }
+       if (length > SINT_MAX(off_t) - offset) {
+               errno = ERANGE;
+               err(EXIT_FAILURE, _("invalid range specified"));
+       }
 
        /* O_CREAT makes sense only for the default fallocate(2) behavior
         * when mode is no specified and new space is allocated */