CVS commit: src/sys/netinet6

["Ryota Ozaki" <ozaki-r%netbsd.org@localhost>]

Module Name:    src
Committed By:   ozaki-r
Date:           Tue Nov  6 04:27:41 UTC 2018

Modified Files:
        src/sys/netinet6: udp6_usrreq.c

Log Message:
Restore the length check of a sockaddr passed from userland at udp6_output

A sockaddr with invalid length could be passed to the network stack resulting in
a kernel panic like this:

        panic: sockaddr_copy: source too long, 28 < 128 bytes
        fatal breakpoint trap in supervisor mode
        trap type 1 code 0 rip 0xffffffff80216c35 cs 0x8 rflags 0x246 cr2 0x7f7ff7ef3000 ilevel 0x4 rsp 0xffff80003308b690
        curlwp 0xfffffe803e11ca40 pid 48.1 lowest kstack 0xffff8000330852c0
        Stopped in pid 48.1 (a.out) at  netbsd:breakpoint+0x5:  leave
        db{1}> bt
        breakpoint() at netbsd:breakpoint+0x5
        vpanic() at netbsd:vpanic+0x140
        panic() at netbsd:panic+0x3c
        sockaddr_copy() at netbsd:sockaddr_copy+0x95
        rtcache_setdst() at netbsd:rtcache_setdst+0x73
        rtcache_lookup2() at netbsd:rtcache_lookup2+0x56
        in6_selectroute() at netbsd:in6_selectroute+0x184
        in6_selectsrc() at netbsd:in6_selectsrc+0x119
        udp6_output() at netbsd:udp6_output+0x25e
        udp6_send_wrapper() at netbsd:udp6_send_wrapper+0x8a
        sosend() at netbsd:sosend+0x7bf
        do_sys_sendmsg_so() at netbsd:do_sys_sendmsg_so+0x28e
        do_sys_sendmsg() at netbsd:do_sys_sendmsg+0x89
        sys_sendto() at netbsd:sys_sendto+0x5c
        syscall() at netbsd:syscall+0x1ed
        --- syscall (number 133) ---
        7f7ff790173a:

Reported by Paul Ripke


To generate a diff of this commit:
cvs rdiff -u -r1.142 -r1.143 src/sys/netinet6/udp6_usrreq.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.