Skip to content
Linux Systems Field Manual

linux/net/socket.c

Imported from _research/manual-study-linux/file-notes/linux__net__socket.c.md.

File Notes: net/socket.c

Status: reviewed.

Purpose: socket syscall and protocol dispatch entrypoint.

Review target: socket lifecycle, protocol registration, operation dispatch, and AI-observable network policy hooks.

Evidence

  • sock_alloc_file() at line 525 wraps a socket in a file object.
  • sock_map_fd() at line 553 installs that file into a descriptor table.
  • sockfd_lookup() at line 601 converts descriptors back into sockets.
  • sock_alloc() at line 680 allocates socket objects; __sock_release() line 701 and sock_release() line 736 tear them down.
  • sock_sendmsg() at line 801 and sock_recvmsg() at line 1144 dispatch I/O.
  • __sock_create() at line 1580 constructs protocol-backed sockets.
  • __sys_socket() at line 1788 and SYSCALL_DEFINE3(socket) at line 1805 are user entry points.
  • Bind/listen/accept/connect paths appear around lines 1912-2118.

Design Notes

Sockets use the same handle membrane as files while routing behavior to protocol operation tables. A Rust design should distinguish descriptor handles, socket state, protocol traits, and namespace/credential context.