X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=acl.c;fp=acl.c;h=75fdc55b12842890136afec74e70125f81b6318c;hb=f17981539ec6877f404b1dfb2e59b55467886e67;hp=10f56bf1bd90fd62e1bb129140365fbed3c2e136;hpb=71c22c2bb151244b2d3db7aa5a1e4a7fec7d2d83;p=paraslash.git

diff --git a/acl.c b/acl.c
index 10f56bf1..75fdc55b 100644
--- a/acl.c
+++ b/acl.c
@@ -31,10 +31,12 @@ struct access_info {
 /**
  * Return true if addr_1 matches addr_2 in the first `netmask' bits.
  */
-static int v4_addr_match(uint32_t addr_1, uint32_t addr_2, uint8_t netmask)
+static bool v4_addr_match(uint32_t addr_1, uint32_t addr_2, uint8_t netmask)
 {
 	uint32_t mask = ~0U;
 
+	if (netmask == 0) /* avoid 32-bit shift, which is undefined in C. */
+		return true;
 	if (netmask < 32)
 		mask <<= (32 - netmask);
 	return (htonl(addr_1) & mask) == (htonl(addr_2) & mask);