Hello,
> diff --git a/gnumach/ipc/ipc_mqueue.c b/gnumach/ipc/ipc_mqueue.c
> index f770afb..834eb16 100644
> --- a/gnumach/ipc/ipc_mqueue.c
> +++ b/gnumach/ipc/ipc_mqueue.c
> @@ -28,11 +27,11 @@
> * the rights to redistribute these changes.
> */
> /*
> - * File: ipc/ipc_mqueue.c
> - * Author: Rich Draves
> - * Date: 2026
> + * File: ipc/ipc_mqueue.c
> + * Author: Rich Draves / Alperen ERKAN
> + * Date: 2026
> @@ -156,6 +159,8 @@ ipc_mqueue_changed(
>
> /*
> * Routine: ipc_mqueue_send
> + * Author : Alperen ERKAN
> + * 2026
> * Purpose:
> * Send a message to a port. The message holds a reference
> * for the destination port in the msgh_remote_port field.
A couple lines is not copyrightable and does make you sole author of
the function.
> @@ -52,6 +51,10 @@
> #include <ipc/ipc_space.h>
> #include <ipc/ipc_marequest.h>
>
> +/*
> + * An absolute message queue upper limit to prevent OOM and memory
> exhaustion.
> + */
> +#define IPC_MQUEUE_HARD_LIMIT 65536
If we start adding absolute constraints on sizes etc. we'd want to put
that into a header dedicated for that, so people know where to tune
them.
> @@ -180,8 +185,16 @@ ipc_mqueue_send(
> {
> ipc_port_t port;
>
> + /* Defensive C: Checking the incoming message object and destination
> port */
> + if (kmsg == IKM_NULL) {
> + return MACH_SEND_INVALID_DATA;
> + }
Again, hiding bugs.
> port = (ipc_port_t) kmsg->ikm_header.msgh_remote_port;
> - assert(IP_VALID(port));
> +
> + if (!IP_VALID(port)) {
> + return MACH_SEND_INVALID_DEST;
> + }
If userland passed a bogus port it should have been tested way before
this.
> @@ -230,17 +243,17 @@ ipc_mqueue_send(
> }
>
> /*
> - * Don't block if:
> - * 1) We're under the queue limit.
> - * 2) Caller used the MACH_SEND_ALWAYS internal option.
> - * 3) Message is sent to a send-once right.
> - */
> -
> - if ((port->ip_msgcount < port->ip_qlimit) ||
> - (option & MACH_SEND_ALWAYS) ||
> - (MACH_MSGH_BITS_REMOTE(kmsg->ikm_header.msgh_bits) ==
> - MACH_MSG_TYPE_PORT_SEND_ONCE))
> - break;
> + * Don't block if:
> + * 1) We're under the queue limit.
> + * 2) Caller used MACH_SEND_ALWAYS but we are under the hard safety
> limit.
> + * 3) Message is sent to a send-once right.
> + */
Avoid mangling the existing content.
> +
> + if ((port->ip_msgcount < port->ip_qlimit) ||
> + ((option & MACH_SEND_ALWAYS) && (port->ip_msgcount <
> IPC_MQUEUE_HARD_LIMIT)) ||
? No, you are making ipc_mqueue_send ignore the port->ip_qlimit.
> + (MACH_MSGH_BITS_REMOTE(kmsg->ikm_header.msgh_bits) ==
> + MACH_MSG_TYPE_PORT_SEND_ONCE))
> + break;
>
> /* must block waiting for queue to clear */
>
> @@ -263,45 +276,49 @@ ipc_mqueue_send(
> counter(c_ipc_mqueue_send_block++);
> thread_block(thread_no_continuation);
> ip_lock(port);
> -
> +
> /* why did we wake up? */
>
> - if (self->ith_state == MACH_MSG_SUCCESS)
> - continue;
> - assert(self->ith_state == MACH_SEND_IN_PROGRESS);
> + if (self->ith_state == MACH_MSG_SUCCESS) {
> + self->ith_state = MACH_MSG_SUCCESS; // veya temiz durum
> sıfırlaması
Always English, please. And this does not do anything.
> + continue;
> + }
> + assert(self->ith_state == MACH_SEND_IN_PROGRESS);
Again avoid mangling the indentation.
>
> - /* take ourselves off blocked queue */
> + /* take ourselves off blocked queue under port lock */
> + ipc_thread_rmqueue(&port->ip_blocked, self);
> +
> + /* [DEFENSIVE]: Clear state to prevent stale status reuse */
> + self->ith_state = MACH_MSG_SUCCESS;
>
> - ipc_thread_rmqueue(&port->ip_blocked, self);
> + /*
> + * Thread wakeup-reason field tells us why
> + * the wait was interrupted.
> + */
>
> - /*
> - * Thread wakeup-reason field tells us why
> - * the wait was interrupted.
> - */
> + switch (self->ith_wait_result) {
> + case THREAD_INTERRUPTED:
> + /* send was interrupted - give up */
This is completely mangled. No idea if there is anything to read here.
Samuel
