From: Sabrina Dubroca Date: Fri, 22 Jul 2022 09:16:27 +0000 (+0200) Subject: macsec: fix NULL deref in macsec_add_rxsa X-Git-Tag: v5.15.73~1864 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=8991687d3bcf6b031b5679d7bc6dfaad68e6dcc4;p=platform%2Fkernel%2Flinux-rpi.git macsec: fix NULL deref in macsec_add_rxsa [ Upstream commit f46040eeaf2e523a4096199fd93a11e794818009 ] Commit 48ef50fa866a added a test on tb_sa[MACSEC_SA_ATTR_PN], but nothing guarantees that it's not NULL at this point. The same code was added to macsec_add_txsa, but there it's not a problem because validate_add_txsa checks that the MACSEC_SA_ATTR_PN attribute is present. Note: it's not possible to reproduce with iproute, because iproute doesn't allow creating an SA without specifying the PN. Fixes: 48ef50fa866a ("macsec: Netlink support of XPN cipher suites (IEEE 802.1AEbw)") Link: https://bugzilla.kernel.org/show_bug.cgi?id=208315 Reported-by: Frantisek Sumsal Signed-off-by: Sabrina Dubroca Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index e53b403..f72d438 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -1751,7 +1751,8 @@ static int macsec_add_rxsa(struct sk_buff *skb, struct genl_info *info) } pn_len = secy->xpn ? MACSEC_XPN_PN_LEN : MACSEC_DEFAULT_PN_LEN; - if (nla_len(tb_sa[MACSEC_SA_ATTR_PN]) != pn_len) { + if (tb_sa[MACSEC_SA_ATTR_PN] && + nla_len(tb_sa[MACSEC_SA_ATTR_PN]) != pn_len) { pr_notice("macsec: nl: add_rxsa: bad pn length: %d != %d\n", nla_len(tb_sa[MACSEC_SA_ATTR_PN]), pn_len); rtnl_unlock();