From a46c68debf3be3a477a69ccbf0a1d050df841676 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Maciej=20=C5=BBenczykowski?= Date: Mon, 29 Jul 2024 17:17:48 -0700 Subject: [PATCH] ipv6: fix ndisc_is_useropt() handling for PIO MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The current logic only works if the PIO is between two other ND user options. This fixes it so that the PIO can also be either before or after other ND user options (for example the first or last option in the RA). side note: there's actually Android tests verifying a portion of the old broken behaviour, so: https://android-review.googlesource.com/c/kernel/tests/+/3196704 fixes those up. Cc: Jen Linkova Cc: Lorenzo Colitti Cc: Patrick Rohr Cc: David Ahern Cc: YOSHIFUJI Hideaki / 吉藤英明 Cc: Jakub Kicinski Signed-off-by: Maciej Żenczykowski Fixes: 048c796beb6e ("ipv6: adjust ndisc_is_useropt() to also return true for PIO") Link: https://patch.msgid.link/20240730001748.147636-1-maze@google.com Signed-off-by: Paolo Abeni --- net/ipv6/ndisc.c | 34 ++++++++++++++++++---------------- 1 file changed, 18 insertions(+), 16 deletions(-) diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c index 70a0b2ad6bd7..b8eec1b6cc2c 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -227,6 +227,7 @@ struct ndisc_options *ndisc_parse_options(const struct net_device *dev, return NULL; memset(ndopts, 0, sizeof(*ndopts)); while (opt_len) { + bool unknown = false; int l; if (opt_len < sizeof(struct nd_opt_hdr)) return NULL; @@ -262,22 +263,23 @@ struct ndisc_options *ndisc_parse_options(const struct net_device *dev, break; #endif default: - if (ndisc_is_useropt(dev, nd_opt)) { - ndopts->nd_useropts_end = nd_opt; - if (!ndopts->nd_useropts) - ndopts->nd_useropts = nd_opt; - } else { - /* - * Unknown options must be silently ignored, - * to accommodate future extension to the - * protocol. - */ - ND_PRINTK(2, notice, - "%s: ignored unsupported option; type=%d, len=%d\n", - __func__, - nd_opt->nd_opt_type, - nd_opt->nd_opt_len); - } + unknown = true; + } + if (ndisc_is_useropt(dev, nd_opt)) { + ndopts->nd_useropts_end = nd_opt; + if (!ndopts->nd_useropts) + ndopts->nd_useropts = nd_opt; + } else if (unknown) { + /* + * Unknown options must be silently ignored, + * to accommodate future extension to the + * protocol. + */ + ND_PRINTK(2, notice, + "%s: ignored unsupported option; type=%d, len=%d\n", + __func__, + nd_opt->nd_opt_type, + nd_opt->nd_opt_len); } next_opt: opt_len -= l;