fix parent-memory-clobber in posix_spawn (environ)

[musl] / src / process / posix_spawn.c

diff --git a/src/process/posix_spawn.c b/src/process/posix_spawn.c
index 604756e..c3e800b 100644 (file)
--- a/src/process/posix_spawn.c
+++ b/src/process/posix_spawn.c
@@ -4,14 +4,22 @@
 #include <stdint.h>
 #include <fcntl.h>
 #include "syscall.h"
+#include "pthread_impl.h"
 #include "fdop.h"
+#include "libc.h"
 
 extern char **environ;
 
+static void dummy_0()
+{
+}
+weak_alias(dummy_0, __acquire_ptc);
+weak_alias(dummy_0, __release_ptc);
+
 pid_t __vfork(void);
 
 int __posix_spawnx(pid_t *restrict res, const char *restrict path,
-       int (*exec)(const char *, char *const *),
+       int (*exec)(const char *, char *const *, char *const *),
        const posix_spawn_file_actions_t *fa,
        const posix_spawnattr_t *restrict attr,
        char *const argv[restrict], char *const envp[restrict])
@@ -23,8 +31,11 @@ int __posix_spawnx(pid_t *restrict res, const char *restrict path,
 
        if (!attr) attr = &dummy_attr;
 
-       sigprocmask(SIG_BLOCK, (void *)(uint64_t []){-1}, &oldmask);
+       sigprocmask(SIG_BLOCK, SIGALL_SET, &oldmask);
+
+       __acquire_ptc();
        pid = __vfork();
+       __release_ptc();
 
        if (pid) {
                sigprocmask(SIG_SETMASK, &oldmask, 0);
@@ -33,14 +44,14 @@ int __posix_spawnx(pid_t *restrict res, const char *restrict path,
                return 0;
        }
 
-       for (i=1; i<=64; i++) {
+       for (i=1; i<=8*__SYSCALL_SSLEN; i++) {
                struct sigaction sa;
-               sigaction(i, 0, &sa);
-               if (sa.sa_handler!=SIG_IGN ||
+               __libc_sigaction(i, 0, &sa);
+               if (sa.sa_handler!=SIG_DFL && (sa.sa_handler!=SIG_IGN ||
                    ((attr->__flags & POSIX_SPAWN_SETSIGDEF)
-                    && sigismember(&attr->__def, i) )) {
+                    && sigismember(&attr->__def, i) ))) {
                        sa.sa_handler = SIG_DFL;
-                       sigaction(i, &sa, 0);
+                       __libc_sigaction(i, &sa, 0);
                }
        }
 
@@ -84,8 +95,7 @@ int __posix_spawnx(pid_t *restrict res, const char *restrict path,
        sigprocmask(SIG_SETMASK, (attr->__flags & POSIX_SPAWN_SETSIGMASK)
                ? &attr->__mask : &oldmask, 0);
 
-       if (envp) environ = (char **)envp;
-       exec(path, argv);
+       exec(path, argv, envp ? envp : environ);
        _exit(127);
 
        return 0;
@@ -96,5 +106,5 @@ int posix_spawn(pid_t *restrict res, const char *restrict path,
        const posix_spawnattr_t *restrict attr,
        char *const argv[restrict], char *const envp[restrict])
 {
-       return __posix_spawnx(res, path, execv, fa, attr, argv, envp);
+       return __posix_spawnx(res, path, execve, fa, attr, argv, envp);
 }