X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fnetwork%2Fsendmsg.c;h=acdfdf29247f0f5a48e713e964ea1fc09f47cd7f;hb=f79b973d92a322800b3e8411ccc95db280d997ae;hp=80cc5f41f6750b2c2cee171158bbe8d7d054577d;hpb=0ab97350f01b42de0f9fd811ee08653169661859;p=musl

diff --git a/src/network/sendmsg.c b/src/network/sendmsg.c
index 80cc5f41..acdfdf29 100644
--- a/src/network/sendmsg.c
+++ b/src/network/sendmsg.c
@@ -8,13 +8,16 @@ ssize_t sendmsg(int fd, const struct msghdr *msg, int flags)
 {
 #if LONG_MAX > INT_MAX
 	struct msghdr h;
-	struct cmsghdr chbuf[1024/sizeof(struct cmsghdr)+1], *c;
+	/* Kernels before 2.6.38 set SCM_MAX_FD to 255, allocate enough
+	 * space to support an SCM_RIGHTS ancillary message with 255 fds.
+	 * Kernels since 2.6.38 set SCM_MAX_FD to 253. */
+	struct cmsghdr chbuf[CMSG_SPACE(255*sizeof(int))/sizeof(struct cmsghdr)+1], *c;
 	if (msg) {
 		h = *msg;
 		h.__pad1 = h.__pad2 = 0;
 		msg = &h;
 		if (h.msg_controllen) {
-			if (h.msg_controllen > 1024) {
+			if (h.msg_controllen > sizeof chbuf) {
 				errno = ENOMEM;
 				return -1;
 			}