git: 3fd9848f1593 - stable/13 - [rtsock] Enforce netmask/RTF_HOST consistency.

[Alexander V. Chernikov]

The branch stable/13 has been updated by melifaro:

URL: https://cgit.FreeBSD.org/src/commit/?id=3fd9848f15930d5ddde4375e540045cc4dc214d6

commit 3fd9848f15930d5ddde4375e540045cc4dc214d6
Author:     Alexander V. Chernikov <melifaro at FreeBSD.org>
AuthorDate: 2021-04-23 21:53:47 +0000
Commit:     Alexander V. Chernikov <melifaro at FreeBSD.org>
CommitDate: 2021-05-04 21:29:36 +0000

    [rtsock] Enforce netmask/RTF_HOST consistency.
    
    Traditionally we had 2 sources of information whether the
     added/delete route request targets network or a host route:
    netmask (RTA_NETMASK) and RTF_HOST flag.
    
    The former one is tricky: netmask can be empty or can explicitly
     specify the host netmask. Parsing netmask sockaddr requires per-family
     parsing and that's what rtsock code traditionally avoided. As a result,
     consistency was not enforced and it was possible to specify network with
     the RTF_HOST flag and vice versa.
    
    Continue normalization efforts from D29826 and D29826 and ensure that
     RTF_HOST flag always reflects host/network data from netmask field.
    
    Differential Revision: https://reviews.freebsd.org/D29958
    MFC after:      2 days
    
    (cherry picked from commit 5d1403a79a3e56403fb63c062252a23fce81e5f1)
---
 sys/net/rtsock.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/sys/net/rtsock.c b/sys/net/rtsock.c
index 405300a394de..6930bd167ac1 100644
--- a/sys/net/rtsock.c
+++ b/sys/net/rtsock.c
@@ -1503,6 +1503,7 @@ cleanup_xaddrs_inet(struct rt_addrinfo *info, struct linear_buffer *lb)
 			return (ENOBUFS);
 		fill_sockaddr_inet(mask_sa, mask);
 		info->rti_info[RTAX_NETMASK] = (struct sockaddr *)mask_sa;
+		info->rti_flags &= ~RTF_HOST;
 	} else
 		remove_netmask(info);
 
@@ -1563,6 +1564,7 @@ cleanup_xaddrs_inet6(struct rt_addrinfo *info, struct linear_buffer *lb)
 			return (ENOBUFS);
 		fill_sockaddr_inet6((struct sockaddr_in6 *)sa, &mask, 0);
 		info->rti_info[RTAX_NETMASK] = sa;
+		info->rti_flags &= ~RTF_HOST;
 	} else
 		remove_netmask(info);