[tor-bugs] #22794 [Applications/Tor Browser Sandbox]: Don't open AF_INET/AF_INET6 sockets when AF_LOCAL is configured.

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#22794: Don't open AF_INET/AF_INET6 sockets when AF_LOCAL is configured.
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 Reporter:  yawning                           |          Owner:  yawning
     Type:  defect                            |         Status:  new
 Priority:  Medium                            |      Milestone:
Component:  Applications/Tor Browser Sandbox  |        Version:
 Severity:  Normal                            |     Resolution:
 Keywords:  tbb-security, tbb-sandboxing      |  Actual Points:
Parent ID:                                    |         Points:
 Reviewer:                                    |        Sponsor:
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Comment (by yawning):

 A minimal/self contained LD_PRELOAD that can reproduce the behavior:
 {{{
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <errno.h>
 #include <stdio.h>

 #define _GNU_SOURCE
 #include <unistd.h>
 #include <syscall.h>

 int socket(int domain, int type, int protocol) {
   fprintf(stderr, "stub: socket(%d, 0x%08x, %d)\n", domain, type,
 protocol);
   if (domain != AF_LOCAL) {
     fprintf(stderr, "stub: domain is not AF_LOCAL, rejecting\n");
     errno = EAFNOSUPPORT;
     return -1;
   }
   return syscall(SYS_socket, domain, type, protocol);
 }
 }}}

 And commenting out the rejection (as in always calling `syscall()`,
 regardless of the domain), magically makes things start to work.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/22794#comment:1>
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