netfilter: xtables: change matches to return error code

The following semantic patch does part of the transformation:
// <smpl>
@ rule1 @
struct xt_match ops;
identifier check;
@@
 ops.checkentry = check;

@@
identifier rule1.check;
@@
 check(...) { <...
-return true;
+return 0;
 ...> }

@@
identifier rule1.check;
@@
 check(...) { <...
-return false;
+return -EINVAL;
 ...> }
// </smpl>

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

1 files changed, 1 insertions, 1 deletions

diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index 771ffa7b9aff..18c5b1573f3e 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -2181,7 +2181,7 @@ static int icmp_checkentry(const struct xt_mtchk_param *par)
 	const struct ipt_icmp *icmpinfo = par->matchinfo;
 
 	/* Must specify no unknown invflags */
-	return !(icmpinfo->invflags & ~IPT_ICMP_INV);
+	return (icmpinfo->invflags & ~IPT_ICMP_INV) ? -EINVAL : 0;
 }
 
 /* The built-in targets: standard (NULL) and error. */