diff --git a/arch/alpha/include/uapi/asm/socket.h b/arch/alpha/include/uapi/asm/socket.h index ff310613ae64dab051339f1597991ada923be7f5..e94f621903feed3a4b6cd5644a93d7c8c512a7cb 100644 --- a/arch/alpha/include/uapi/asm/socket.h +++ b/arch/alpha/include/uapi/asm/socket.h @@ -138,6 +138,7 @@ #define SO_RCVMARK 75 #define SO_PASSPIDFD 76 +#define SO_PEERPIDFD 77 #if !defined(__KERNEL__) diff --git a/arch/mips/include/uapi/asm/socket.h b/arch/mips/include/uapi/asm/socket.h index 762dcb80e4ec6828a09870914727e9dfe6d86846..60ebaed28a4cab388997e3567c8df45cc06d02e5 100644 --- a/arch/mips/include/uapi/asm/socket.h +++ b/arch/mips/include/uapi/asm/socket.h @@ -149,6 +149,7 @@ #define SO_RCVMARK 75 #define SO_PASSPIDFD 76 +#define SO_PEERPIDFD 77 #if !defined(__KERNEL__) diff --git a/arch/parisc/include/uapi/asm/socket.h b/arch/parisc/include/uapi/asm/socket.h index df16a3e16d645dd5a79308cd26bdc1af80a1b67a..be264c2b1a1178806133eb651cf452fcf0b6523a 100644 --- a/arch/parisc/include/uapi/asm/socket.h +++ b/arch/parisc/include/uapi/asm/socket.h @@ -130,6 +130,7 @@ #define SO_RCVMARK 0x4049 #define SO_PASSPIDFD 0x404A +#define SO_PEERPIDFD 0x404B #if !defined(__KERNEL__) diff --git a/arch/sparc/include/uapi/asm/socket.h b/arch/sparc/include/uapi/asm/socket.h index 6e2847804fea762a3cb10903fb0cb15e64a7bc91..682da3714686c9b2d659062b05d86722a47e11ed 100644 --- a/arch/sparc/include/uapi/asm/socket.h +++ b/arch/sparc/include/uapi/asm/socket.h @@ -131,6 +131,7 @@ #define SO_RCVMARK 0x0054 #define SO_PASSPIDFD 0x0055 +#define SO_PEERPIDFD 0x0056 #if !defined(__KERNEL__) diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h index b76169fdb80b1163484d1bd4dbd7708debbfb337..8ce8a39a1e5f0094146a48779a4580ade7d647df 100644 --- a/include/uapi/asm-generic/socket.h +++ b/include/uapi/asm-generic/socket.h @@ -133,6 +133,7 @@ #define SO_RCVMARK 75 #define SO_PASSPIDFD 76 +#define SO_PEERPIDFD 77 #if !defined(__KERNEL__) diff --git a/net/core/sock.c b/net/core/sock.c index ed4eb4ba738b6fa162b3070fcad7d96e97d2a96a..ea66b1afadd072f0847ae96d166c2abb9937c9cd 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -1758,6 +1758,39 @@ int sk_getsockopt(struct sock *sk, int level, int optname, goto lenout; } + case SO_PEERPIDFD: + { + struct pid *peer_pid; + struct file *pidfd_file = NULL; + int pidfd; + + if (len > sizeof(pidfd)) + len = sizeof(pidfd); + + spin_lock(&sk->sk_peer_lock); + peer_pid = get_pid(sk->sk_peer_pid); + spin_unlock(&sk->sk_peer_lock); + + if (!peer_pid) + return -ESRCH; + + pidfd = pidfd_prepare(peer_pid, 0, &pidfd_file); + put_pid(peer_pid); + if (pidfd < 0) + return pidfd; + + if (copy_to_sockptr(optval, &pidfd, len) || + copy_to_sockptr(optlen, &len, sizeof(int))) { + put_unused_fd(pidfd); + fput(pidfd_file); + + return -EFAULT; + } + + fd_install(pidfd, pidfd_file); + return 0; + } + case SO_PEERGROUPS: { const struct cred *cred; diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index c46c2f5d860c4e7db5bc7031f1f45985623280ec..73c61a010b0163d0bc2244b1ab0b200163f94a44 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -921,11 +921,26 @@ static void unix_unhash(struct sock *sk) */ } +static bool unix_bpf_bypass_getsockopt(int level, int optname) +{ + if (level == SOL_SOCKET) { + switch (optname) { + case SO_PEERPIDFD: + return true; + default: + return false; + } + } + + return false; +} + struct proto unix_dgram_proto = { .name = "UNIX", .owner = THIS_MODULE, .obj_size = sizeof(struct unix_sock), .close = unix_close, + .bpf_bypass_getsockopt = unix_bpf_bypass_getsockopt, #ifdef CONFIG_BPF_SYSCALL .psock_update_sk_prot = unix_dgram_bpf_update_proto, #endif @@ -937,6 +952,7 @@ struct proto unix_stream_proto = { .obj_size = sizeof(struct unix_sock), .close = unix_close, .unhash = unix_unhash, + .bpf_bypass_getsockopt = unix_bpf_bypass_getsockopt, #ifdef CONFIG_BPF_SYSCALL .psock_update_sk_prot = unix_stream_bpf_update_proto, #endif diff --git a/tools/include/uapi/asm-generic/socket.h b/tools/include/uapi/asm-generic/socket.h index fbbc4bf53ee3f0753b9b1d7059c4e7ee2f1d7b66..54d9c8bf7c55f0bbb81ab642f0fa0a4b2cdd5d1d 100644 --- a/tools/include/uapi/asm-generic/socket.h +++ b/tools/include/uapi/asm-generic/socket.h @@ -122,6 +122,7 @@ #define SO_RCVMARK 75 #define SO_PASSPIDFD 76 +#define SO_PEERPIDFD 77 #if !defined(__KERNEL__)