From 9ca718743ad8402958637bfc196d7b62371a1b9f Mon Sep 17 00:00:00 2001 From: Francis Laniel Date: Sun, 15 Nov 2020 18:08:05 +0100 Subject: Modify return value of nla_strlcpy to match that of strscpy. nla_strlcpy now returns -E2BIG if src was truncated when written to dst. It also returns this error value if dstsize is 0 or higher than INT_MAX. For example, if src is "foo\0" and dst is 3 bytes long, the result will be: 1. "foG" after memcpy (G means garbage). 2. "fo\0" after memset. 3. -E2BIG is returned because src was not completely written into dst. The callers of nla_strlcpy were modified to take into account this modification. Signed-off-by: Francis Laniel Reviewed-by: Kees Cook Signed-off-by: Jakub Kicinski --- include/net/pkt_cls.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/net/pkt_cls.h') diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h index d4d461236351..db9a828f4f4f 100644 --- a/include/net/pkt_cls.h +++ b/include/net/pkt_cls.h @@ -512,7 +512,7 @@ tcf_change_indev(struct net *net, struct nlattr *indev_tlv, char indev[IFNAMSIZ]; struct net_device *dev; - if (nla_strlcpy(indev, indev_tlv, IFNAMSIZ) >= IFNAMSIZ) { + if (nla_strlcpy(indev, indev_tlv, IFNAMSIZ) < 0) { NL_SET_ERR_MSG_ATTR(extack, indev_tlv, "Interface name too long"); return -EINVAL; -- cgit v1.2.3