Fix phpGH-8517: FPM child pointer can be possibly uninitialized

Author: bukka

sapi/fpm/fpm/fpm_children.c

@@ -121,7 +121,7 @@ static void fpm_child_unlink(struct fpm_child_s *child) /* {{{ */
 }
 /* }}} */
 
-static struct fpm_child_s *fpm_child_find(pid_t pid) /* {{{ */
+struct fpm_child_s *fpm_child_find(pid_t pid) /* {{{ */
 {
 	struct fpm_worker_pool_s *wp;
 	struct fpm_child_s *child = 0;

sapi/fpm/fpm/fpm_children.h

@@ -10,13 +10,14 @@
 #include "fpm_events.h"
 #include "zlog.h"
 
+struct fpm_child_s;
+
 int fpm_children_create_initial(struct fpm_worker_pool_s *wp);
 int fpm_children_free(struct fpm_child_s *child);
 void fpm_children_bury();
 int fpm_children_init_main();
 int fpm_children_make(struct fpm_worker_pool_s *wp, int in_event_loop, int nb_to_spawn, int is_debug);
-
-struct fpm_child_s;
+struct fpm_child_s *fpm_child_find(pid_t pid);
 
 struct fpm_child_s {
 	struct fpm_child_s *prev, *next;

sapi/fpm/fpm/fpm_stdio.c

@@ -129,7 +129,10 @@ static void fpm_stdio_child_said(struct fpm_event_s *ev, short which, void *arg)
 	if (!arg) {
 		return;
 	}
-	child = (struct fpm_child_s *)arg;
+	child = fpm_child_find((intptr_t) arg);
+	if (!child) {
+		return;
+	}
 
 	is_stdout = (fd == child->fd_stdout);
 	if (is_stdout) {
@@ -275,10 +278,10 @@ int fpm_stdio_parent_use_pipes(struct fpm_child_s *child) /* {{{ */
 	child->fd_stdout = fd_stdout[0];
 	child->fd_stderr = fd_stderr[0];
 
-	fpm_event_set(&child->ev_stdout, child->fd_stdout, FPM_EV_READ, fpm_stdio_child_said, child);
+	fpm_event_set(&child->ev_stdout, child->fd_stdout, FPM_EV_READ, fpm_stdio_child_said, (void *) (intptr_t) child->pid);
 	fpm_event_add(&child->ev_stdout, 0);
 
-	fpm_event_set(&child->ev_stderr, child->fd_stderr, FPM_EV_READ, fpm_stdio_child_said, child);
+	fpm_event_set(&child->ev_stderr, child->fd_stderr, FPM_EV_READ, fpm_stdio_child_said, (void *) (intptr_t) child->pid);
 	fpm_event_add(&child->ev_stderr, 0);
 	return 0;
 }