fix faccessat AT_EACCESS path not to leave zombie processes

I mistakenly assumed that clone without a signal produced processes
that would not become zombies; however, waitpid with __WCLONE is
required to release their pids.

diff --git a/src/unistd/faccessat.c b/src/unistd/faccessat.c
index 821e13f57504edbe6f6664379abe88ce11755f9d..76bbd4c72a16dbea7cdef397aa12ccb013adaa85 100644 (file)
--- a/src/unistd/faccessat.c
+++ b/src/unistd/faccessat.c
@@ -1,5 +1,6 @@
 #include <unistd.h>
 #include <fcntl.h>
+#include <sys/wait.h>
 #include "syscall.h"
 #include "pthread_impl.h"
 
@@ -32,6 +33,8 @@ int faccessat(int fd, const char *filename, int amode, int flag)
 
        char stack[1024];
        sigset_t set;
+       pid_t pid;
+       int status;
        int ret, p[2];
 
        if (pipe2(p, O_CLOEXEC)) return __syscall_ret(-EBUSY);
@@ -39,12 +42,13 @@ int faccessat(int fd, const char *filename, int amode, int flag)
 
        __block_all_sigs(&set);
        
-       ret = __clone(checker, stack+sizeof stack, 0, &c);
+       pid = __clone(checker, stack+sizeof stack, 0, &c);
        __syscall(SYS_close, p[1]);
 
-       if (ret<0 || __syscall(SYS_read, p[0], &ret, sizeof ret) != sizeof(ret))
+       if (pid<0 || __syscall(SYS_read, p[0], &ret, sizeof ret) != sizeof(ret))
                ret = -EBUSY;
        __syscall(SYS_close, p[0]);
+       __syscall(SYS_wait4, pid, &status, __WCLONE, 0);
 
        __restore_sigs(&set);