Bug 232920

Another related issue is:

The function 'linux_getsockname' in 'linux_socket.c' calls 'bsd_to_linux_sockaddr', and it calls 'bsd_to_linux_domain' to convert 'sa_family' from BSD domain to Linux domain.
 
 But after calling  'bsd_to_linux_sockaddr', 'linux_sa_put' is called, and it calls 'bsd_to_linux_domain' to convert 'sa_family' from BSD domain to Linux domain again.
But the 'sa_family' has already been converted.
Since the value of AF_INTE6 and LINUX_AF_INET6 is different, and converting twice will cause issue. 

Test Case below:
get_sock_name_case.c
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include <sys/socket.h>
#include <netinet/in.h>

int main()
{
    int sock;
    int len = sizeof(struct sockaddr_in6);
    struct sockaddr_in6 add;

    if ((sock=socket(AF_INET6, SOCK_STREAM, 0)) < 0)
    {
        perror("sock");
        return 1;
    }

    memset(&add, 0, len);
    add.sin6_family = AF_INET6;
    add.sin6_port = htons(10000);
    printf("bind address type:%d-port:%d\n", add.sin6_family, ntohs(add.sin6_port));

    if (bind(sock, (struct sockaddr *)&add, len)<0)
    {
        perror("bind");
        return 1;
    }

    memset(&add, 0, len);
    getsockname(sock, (struct sockaddr *)&add, &len);
    printf("getsockname address type:%d-port:%d\n", add.sin6_family, ntohs(add.sin6_port));

    return 0;
}

result:
case in linux
user@~/:uname -a
Linux CentOS 3.10.0-693.el7.x86_64 #1 SMP Tue Aug 22 21:09:27 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
user@~/:cat /etc/redhat-release
CentOS Linux release 7.4.1708 (Core)

bind address type:10-port:10000
getsockname address type:10-port:10000

case in freebsd
[user@host ~]# uname -a
FreeBSD host 12.0-RELEASE FreeBSD 12.0-RELEASE #94 308a36af9(master)-dirty: Mon Feb 25 16:33:41 CST 2019     KERNCONF  amd64
[user@host ~]# ./case
bind address type:10-port:10000
getsockname address type:3-port:10000

Comment 2 commit-hook 2019-05-13 17:49:02 UTC

A commit references this bug:

Author: dchagin
Date: Mon May 13 17:48:17 UTC 2019
New revision: 347533
URL: https://svnweb.freebsd.org/changeset/base/347533

Log:
  Our bsd_to_linux_sockaddr() and linux_to_bsd_sockaddr() functions
  alter the userspace sockaddr to convert the format between linux and BSD versions.
  That's the minimum 3 of copyin/copyout operations for one syscall.

  Also some syscall uses linux_sa_put() and linux_getsockaddr() when load
  sockaddr to userspace or from userspace accordingly.

  To avoid this chaos, especially converting sockaddr in the userspace,
  rewrite these 4 functions to convert sockaddr only in kernel and leave
  only 2 of this functions.

  Also in order to reduce duplication between MD parts of the Linuxulator put
  struct sockaddr conversion functions that are MI out into linux_common module.

  PR:		232920
  MFC after:	2 weeks
  Differential Revision:	https://reviews.freebsd.org/D20157

Changes:
  head/sys/compat/linux/linux.c
  head/sys/compat/linux/linux.h
  head/sys/compat/linux/linux_common.h
  head/sys/compat/linux/linux_socket.c
  head/sys/compat/linux/linux_socket.h
  head/sys/modules/linux_common/Makefile

Comment 3 Mark Johnston 2020-01-16 19:20:17 UTC

Should this PR be kept open?  I note that there was no MFC.

Comment 4 Dmitry Chagin 2020-01-21 15:35:55 UTC

(In reply to Mark Johnston from comment #3)
will mfc it soon

Comment 5 commit-hook 2020-08-24 15:46:06 UTC

A commit references this bug:

Author: trasz
Date: Mon Aug 24 15:45:43 UTC 2020
New revision: 364693
URL: https://svnweb.freebsd.org/changeset/base/364693

Log:
  MFC r347533 by dchagin:

  Our bsd_to_linux_sockaddr() and linux_to_bsd_sockaddr() functions
  alter the userspace sockaddr to convert the format between linux and BSD versions.
  That's the minimum 3 of copyin/copyout operations for one syscall.

  Also some syscall uses linux_sa_put() and linux_getsockaddr() when load
  sockaddr to userspace or from userspace accordingly.

  To avoid this chaos, especially converting sockaddr in the userspace,
  rewrite these 4 functions to convert sockaddr only in kernel and leave
  only 2 of this functions.

  Also in order to reduce duplication between MD parts of the Linuxulator put
  struct sockaddr conversion functions that are MI out into linux_common module.

  PR:		232920

Changes:
_U  stable/12/
  stable/12/sys/compat/linux/linux.c
  stable/12/sys/compat/linux/linux.h
  stable/12/sys/compat/linux/linux_common.h
  stable/12/sys/compat/linux/linux_socket.c
  stable/12/sys/compat/linux/linux_socket.h
  stable/12/sys/modules/linux_common/Makefile