From: Benedict Wong Date: Mon, 14 Jan 2019 19:24:38 +0000 (-0800) Subject: xfrm: Make set-mark default behavior backward compatible X-Git-Tag: v5.0-rc5~34^2~25^2 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=e2612cd496e7b465711d219ea6118893d7253f52;p=linux.git xfrm: Make set-mark default behavior backward compatible Fixes 9b42c1f179a6, which changed the default route lookup behavior for tunnel mode SAs in the outbound direction to use the skb mark, whereas previously mark=0 was used if the output mark was unspecified. In mark-based routing schemes such as Android’s, this change in default behavior causes routing loops or lookup failures. This patch restores the default behavior of using a 0 mark while still incorporating the skb mark if the SET_MARK (and SET_MARK_MASK) is specified. Tested with additions to Android's kernel unit test suite: https://android-review.googlesource.com/c/kernel/tests/+/860150 Fixes: 9b42c1f179a6 ("xfrm: Extend the output_mark to support input direction and masking") Signed-off-by: Benedict Wong Signed-off-by: Steffen Klassert --- diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index 8cfd75b62396..ba0a4048c846 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -2600,7 +2600,10 @@ static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy, dst_copy_metrics(dst1, dst); if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { - __u32 mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]); + __u32 mark = 0; + + if (xfrm[i]->props.smark.v || xfrm[i]->props.smark.m) + mark = xfrm_smark_get(fl->flowi_mark, xfrm[i]); family = xfrm[i]->props.family; dst = xfrm_dst_lookup(xfrm[i], tos, fl->flowi_oif,