fix rejection of dns responses with pointers past 512 byte offset

[musl] / src / process / fexecve.c

diff --git a/src/process/fexecve.c b/src/process/fexecve.c
index 5939181..554c198 100644 (file)
--- a/src/process/fexecve.c
+++ b/src/process/fexecve.c
@@ -1,12 +1,15 @@
+#define _GNU_SOURCE
 #include <unistd.h>
-#include <stdio.h>
 #include <errno.h>
+#include <fcntl.h>
+#include "syscall.h"
 
 int fexecve(int fd, char *const argv[], char *const envp[])
 {
-       static const char proc[] = "/proc/self/fd/%d";
-       char buf[sizeof proc + 3*sizeof(int)];
-       snprintf(buf, sizeof buf, proc, fd);
+       int r = __syscall(SYS_execveat, fd, "", argv, envp, AT_EMPTY_PATH);
+       if (r != -ENOSYS) return __syscall_ret(r);
+       char buf[15 + 3*sizeof(int)];
+       __procfdname(buf, fd);
        execve(buf, argv, envp);
        if (errno == ENOENT) errno = EBADF;
        return -1;