When delinearizing, an all-zero mask didn't qualify as prefix. Therefore a statement: | ip daddr 0.0.0.0/0 would be printed as: | ip daddr & 0.0.0.0 == 0.0.0.0 To fix this, expr_mask_is_prefix() must return true if the initial 1-bit search fails (the given value must be zero in this case). Additionally, a shortcut is needed in conversion algorithm of expr_mask_to_prefix() to not turn the zero prefix into a 1 by accident. Signed-off-by: Phil Sutter <phil@xxxxxx> --- src/netlink_delinearize.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/netlink_delinearize.c b/src/netlink_delinearize.c index 2c9b0a32a932e..c018e78b02925 100644 --- a/src/netlink_delinearize.c +++ b/src/netlink_delinearize.c @@ -1734,6 +1734,8 @@ static unsigned int expr_mask_to_prefix(const struct expr *expr) unsigned long n; n = mpz_scan1(expr->value, 0); + if (n == ULONG_MAX) + return 0; return mpz_scan0(expr->value, n + 1) - n; } @@ -1744,7 +1746,7 @@ static bool expr_mask_is_prefix(const struct expr *expr) n1 = mpz_scan1(expr->value, 0); if (n1 == ULONG_MAX) - return false; + return true; n2 = mpz_scan0(expr->value, n1 + 1); if (n2 < expr->len || n2 == ULONG_MAX) return false; -- 2.21.0
