fix fchown fallback on arches without chown(2)

[musl] / src / env / __libc_start_main.c

diff --git a/src/env/__libc_start_main.c b/src/env/__libc_start_main.c
index 2a8698b..5c79be2 100644 (file)
--- a/src/env/__libc_start_main.c
+++ b/src/env/__libc_start_main.c
@@ -1,21 +1,23 @@
 #include <elf.h>
+#include <poll.h>
+#include <fcntl.h>
+#include <signal.h>
+#include "syscall.h"
+#include "atomic.h"
 #include "libc.h"
 
 void __init_tls(size_t *);
-void __init_security(size_t *);
-void __init_ldso_ctors(void);
 
-#ifndef SHARED
-static void dummy() {}
+static void dummy(void) {}
 weak_alias(dummy, _init);
-extern void (*const __init_array_start)() __attribute__((weak));
-extern void (*const __init_array_end)() __attribute__((weak));
-#endif
 
-#define AUX_CNT 38
+__attribute__((__weak__, __visibility__("hidden")))
+extern void (*const __init_array_start)(void), (*const __init_array_end)(void);
 
-extern size_t __hwcap, __sysinfo;
-extern char *__progname, *__progname_full;
+static void dummy1(void *p) {}
+weak_alias(dummy1, __init_ssp);
+
+#define AUX_CNT 38
 
 void __init_libc(char **envp, char *pn)
 {
@@ -26,6 +28,7 @@ void __init_libc(char **envp, char *pn)
        for (i=0; auxv[i]; i+=2) if (auxv[i]<AUX_CNT) aux[auxv[i]] = auxv[i+1];
        __hwcap = aux[AT_HWCAP];
        __sysinfo = aux[AT_SYSINFO];
+       libc.page_size = aux[AT_PAGESZ];
 
        if (pn) {
                __progname = __progname_full = pn;
@@ -33,22 +36,41 @@ void __init_libc(char **envp, char *pn)
        }
 
        __init_tls(aux);
-       __init_security(aux);
+       __init_ssp((void *)aux[AT_RANDOM]);
+
+       if (aux[AT_UID]==aux[AT_EUID] && aux[AT_GID]==aux[AT_EGID]
+               && !aux[AT_SECURE]) return;
+
+       struct pollfd pfd[3] = { {.fd=0}, {.fd=1}, {.fd=2} };
+#ifdef SYS_poll
+       __syscall(SYS_poll, pfd, 3, 0);
+#else
+       __syscall(SYS_ppoll, pfd, 3, &(struct timespec){0}, 0, _NSIG/8);
+#endif
+       for (i=0; i<3; i++) if (pfd[i].revents&POLLNVAL)
+               if (__sys_open("/dev/null", O_RDWR)<0)
+                       a_crash();
+       libc.secure = 1;
 }
 
-int __libc_start_main(int (*main)(int,char **,char **), int argc, char **argv)
+static void libc_start_init(void)
 {
-       char **envp = argv+argc+1;
-
-#ifndef SHARED
-       __init_libc(envp, argv[0]);
        _init();
        uintptr_t a = (uintptr_t)&__init_array_start;
        for (; a<(uintptr_t)&__init_array_end; a+=sizeof(void(*)()))
                (*(void (**)())a)();
-#endif
+}
+
+weak_alias(libc_start_init, __libc_start_init);
+
+int __libc_start_main(int (*main)(int,char **,char **), int argc, char **argv)
+{
+       char **envp = argv+argc+1;
+
+       __init_libc(envp, argv[0]);
+       __libc_start_init();
 
-       /* Pass control to to application */
+       /* Pass control to the application */
        exit(main(argc, argv, envp));
        return 0;
 }