Re: [Crash-utility] [PATCH] Fix for "net -s" option to show an IPv6 address

On 2023/02/09 21:15, Lianbo Jiang wrote: > Currently, the "net -s" command fails to show an IPv6 address. For > example: > > crash> net -s > PID: 305524 TASK: ffff9bc449895580 CPU: 6 COMMAND: "sshd" > FD SOCKET SOCK FAMILY:TYPE SOURCE-PORT DESTINATION-PORT > 3 ffff9bc446e9a680 ffff9bc4455b5940 UNIX:DGRAM > 4 ffff9bc446e9c600 ffff9bc3b2b24e00 INET6:STREAM > > With the patch: > crash> net -s > PID: 305524 TASK: ffff9bc449895580 CPU: 6 COMMAND: "sshd" > FD SOCKET SOCK FAMILY:TYPE SOURCE-PORT DESTINATION-PORT > 3 ffff9bc446e9a680 ffff9bc4455b5940 UNIX:DGRAM > 4 ffff9bc446e9c600 ffff9bc3b2b24e00 INET6:STREAM xxxx:xx:x:xxxx:xxxx:xxxx:xxxx:xxxx-22 yyyy:yy:y:yyyy:yyyy:yyyy:yyyy:yyyy-44870 > > Let's support displaying the IPv6 address and port in the SOURCE-PORT > and DESTINATION-PORT colums. > > Reported-by: Buland Kumar Singh <bsingh(a)redhat.com&gt; > Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com&gt; Good catch, I didn't know "net -s" could print IPv6 addresses... Is this the corresponding kernel patch?

Author: Eric Dumazet <edumazet(a)google.com&gt; Date: Thu Oct 3 15:42:29 2013 -0700 ipv6: make lookups simpler and faster > --- > defs.h | 3 +++ > net.c | 40 ++++++++++++++++++++++++++++------------ > symbols.c | 6 ++++++ > 3 files changed, 37 insertions(+), 12 deletions(-) > > diff --git a/defs.h b/defs.h > index 33a823b7b67c..db20056dc3ed 100644 > --- a/defs.h > +++ b/defs.h > @@ -2204,6 +2204,9 @@ struct offset_table { /* stash of commonly-used offsets */ > long maple_range_64_slot; > long maple_metadata_end; > long maple_metadata_gap; > + long sock_sk_common; > + long sock_common_skc_v6_daddr; > + long sock_common_skc_v6_rcv_saddr; > }; > > struct size_table { /* stash of commonly-used sizes */ > diff --git a/net.c b/net.c > index 7c9c8bd9c98d..7af299d0774d 100644 > --- a/net.c > +++ b/net.c > @@ -198,6 +198,9 @@ net_init(void) > */ > MEMBER_OFFSET_INIT(sock_common_skc_family, > "sock_common", "skc_family"); > + MEMBER_OFFSET_INIT(sock_sk_common, "sock", "__sk_common"); > + MEMBER_OFFSET_INIT(sock_common_skc_v6_daddr, "sock_common", "skc_v6_daddr"); > + MEMBER_OFFSET_INIT(sock_common_skc_v6_rcv_saddr, "sock_common", "skc_v6_rcv_saddr"); > MEMBER_OFFSET_INIT(sock_sk_type, "sock", "sk_type"); > /* > * struct inet_sock { > @@ -1104,19 +1107,32 @@ get_sock_info(ulong sock, char *buf) > break; > > case SOCK_V2: > - if (INVALID_MEMBER(ipv6_pinfo_rcv_saddr) || > - INVALID_MEMBER(ipv6_pinfo_daddr)) > - break; > - > - ipv6_rcv_saddr = ipv6_pinfo + OFFSET(ipv6_pinfo_rcv_saddr); > - ipv6_daddr = ipv6_pinfo + OFFSET(ipv6_pinfo_daddr); > - > - if (!readmem(ipv6_rcv_saddr, KVADDR, u6_addr16_src, SIZE(in6_addr), > - "ipv6_rcv_saddr buffer", QUIET|RETURN_ON_ERROR)) > - break; > - if (!readmem(ipv6_daddr, KVADDR, u6_addr16_dest, SIZE(in6_addr), > - "ipv6_daddr buffer", QUIET|RETURN_ON_ERROR)) > + if (VALID_MEMBER(ipv6_pinfo_rcv_saddr) && > + VALID_MEMBER(ipv6_pinfo_daddr)) { > + ipv6_rcv_saddr = ipv6_pinfo + OFFSET(ipv6_pinfo_rcv_saddr); > + ipv6_daddr = ipv6_pinfo + OFFSET(ipv6_pinfo_daddr); > + > + if (!readmem(ipv6_rcv_saddr, KVADDR, u6_addr16_src, SIZE(in6_addr), > + "ipv6_rcv_saddr buffer", QUIET|RETURN_ON_ERROR)) > + break; > + if (!readmem(ipv6_daddr, KVADDR, u6_addr16_dest, SIZE(in6_addr), > + "ipv6_daddr buffer", QUIET|RETURN_ON_ERROR)) > + break; > + } else if (VALID_MEMBER(sock_sk_common) && VALID_MEMBER(sock_common_skc_v6_daddr) && > + VALID_MEMBER(sock_common_skc_v6_rcv_saddr)) { > + ipv6_rcv_saddr = sock + OFFSET(sock_sk_common) + OFFSET(sock_common_skc_v6_rcv_saddr); > + ipv6_daddr = sock + OFFSET(sock_sk_common) + OFFSET(sock_common_skc_v6_daddr); > + > + if (!readmem(ipv6_rcv_saddr, KVADDR, u6_addr16_src, SIZE(in6_addr), > + "ipv6_rcv_saddr buffer", QUIET|RETURN_ON_ERROR)) > + break; > + if (!readmem(ipv6_daddr, KVADDR, u6_addr16_dest, SIZE(in6_addr), > + "ipv6_daddr buffer", QUIET|RETURN_ON_ERROR)) > + break; > + } else { > + error(INFO, "Invalid member...\n"); This message is unusual and vague, and the output looks not good: (I forced to print this.) crash> net -s 1 PID: 1 TASK: ffff9c6b8159c8c0 CPU: 11 COMMAND: "systemd" FD SOCKET SOCK FAMILY:TYPE SOURCE-PORT DESTINATION-PORT ... 41 ffff9c79974b70c0 ffff9c79afcfb700 INET:DGRAM 0.0.0.0-111 0.0.0.0-0 42 ffff9c79974b1e40 ffff9c7a6f4347c0 net: Invalid member... INET6:STREAM 43 ffff9c79974b1340 ffff9c7a6f43e780 net: Invalid member... INET6:DGRAM 44 ffff9c79974b3180 ffff9c767da66780 UNIX:SEQPACKET ... How about this?

} else { - error(INFO, "Invalid member...\n"); + sprintf(&buf[strlen(buf)], "%s", "(cannot get IPv6 addresses)"); break; 41 ffff9c79974b70c0 ffff9c79afcfb700 INET:DGRAM 0.0.0.0-111 0.0.0.0-0 42 ffff9c79974b1e40 ffff9c7a6f4347c0 INET6:STREAM (cannot get IPv6 addresses) 43 ffff9c79974b1340 ffff9c7a6f43e780 INET6:DGRAM (cannot get IPv6 addresses) 44 ffff9c79974b3180 ffff9c767da66780 UNIX:SEQPACKET Otherwise, looks good, although I would like to tweak some indents a bit.

Kazu > break; > + } > > sprintf(&buf[strlen(buf)], "%*s ", BITS32() ? 22 : 12, > dump_in6_addr_port(u6_addr16_src, sport, buf2, &len)); > diff --git a/symbols.c b/symbols.c > index e38df8aad0f5..d622de722ebd 100644 > --- a/symbols.c > +++ b/symbols.c > @@ -9820,6 +9820,12 @@ dump_offset_table(char *spec, ulong makestruct) > OFFSET(sock_sk_type)); > fprintf(fp, " sock_common_skc_family: %ld\n", > OFFSET(sock_common_skc_family)); > + fprintf(fp, " sock_sk_common: %ld\n", > + OFFSET(sock_sk_common)); > + fprintf(fp, " sock_common_skc_v6_daddr: %ld\n", > + OFFSET(sock_common_skc_v6_daddr)); > + fprintf(fp, " sock_common_skc_v6_rcv_saddr: %ld\n", > + OFFSET(sock_common_skc_v6_rcv_saddr)); > fprintf(fp, " socket_alloc_vfs_inode: %ld\n", > OFFSET(socket_alloc_vfs_inode)); > fprintf(fp, " inet_sock_inet: %ld\n",