x86/compat: Move copy_siginfo_*_user32() to signal_compat.c

[sfrench/cifs-2.6.git] / arch / x86 / kernel / signal_compat.c

diff --git a/arch/x86/kernel/signal_compat.c b/arch/x86/kernel/signal_compat.c
new file mode 100644 (file)
index 0000000..dc3c0b1
--- /dev/null
+++ b/arch/x86/kernel/signal_compat.c
@@ -0,0 +1,95 @@
+#include <linux/compat.h>
+#include <linux/uaccess.h>
+
+int copy_siginfo_to_user32(compat_siginfo_t __user *to, const siginfo_t *from)
+{
+       int err = 0;
+       bool ia32 = test_thread_flag(TIF_IA32);
+
+       if (!access_ok(VERIFY_WRITE, to, sizeof(compat_siginfo_t)))
+               return -EFAULT;
+
+       put_user_try {
+               /* If you change siginfo_t structure, please make sure that
+                  this code is fixed accordingly.
+                  It should never copy any pad contained in the structure
+                  to avoid security leaks, but must copy the generic
+                  3 ints plus the relevant union member.  */
+               put_user_ex(from->si_signo, &to->si_signo);
+               put_user_ex(from->si_errno, &to->si_errno);
+               put_user_ex((short)from->si_code, &to->si_code);
+
+               if (from->si_code < 0) {
+                       put_user_ex(from->si_pid, &to->si_pid);
+                       put_user_ex(from->si_uid, &to->si_uid);
+                       put_user_ex(ptr_to_compat(from->si_ptr), &to->si_ptr);
+               } else {
+                       /*
+                        * First 32bits of unions are always present:
+                        * si_pid === si_band === si_tid === si_addr(LS half)
+                        */
+                       put_user_ex(from->_sifields._pad[0],
+                                         &to->_sifields._pad[0]);
+                       switch (from->si_code >> 16) {
+                       case __SI_FAULT >> 16:
+                               break;
+                       case __SI_SYS >> 16:
+                               put_user_ex(from->si_syscall, &to->si_syscall);
+                               put_user_ex(from->si_arch, &to->si_arch);
+                               break;
+                       case __SI_CHLD >> 16:
+                               if (ia32) {
+                                       put_user_ex(from->si_utime, &to->si_utime);
+                                       put_user_ex(from->si_stime, &to->si_stime);
+                               } else {
+                                       put_user_ex(from->si_utime, &to->_sifields._sigchld_x32._utime);
+                                       put_user_ex(from->si_stime, &to->_sifields._sigchld_x32._stime);
+                               }
+                               put_user_ex(from->si_status, &to->si_status);
+                               /* FALL THROUGH */
+                       default:
+                       case __SI_KILL >> 16:
+                               put_user_ex(from->si_uid, &to->si_uid);
+                               break;
+                       case __SI_POLL >> 16:
+                               put_user_ex(from->si_fd, &to->si_fd);
+                               break;
+                       case __SI_TIMER >> 16:
+                               put_user_ex(from->si_overrun, &to->si_overrun);
+                               put_user_ex(ptr_to_compat(from->si_ptr),
+                                           &to->si_ptr);
+                               break;
+                                /* This is not generated by the kernel as of now.  */
+                       case __SI_RT >> 16:
+                       case __SI_MESGQ >> 16:
+                               put_user_ex(from->si_uid, &to->si_uid);
+                               put_user_ex(from->si_int, &to->si_int);
+                               break;
+                       }
+               }
+       } put_user_catch(err);
+
+       return err;
+}
+
+int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from)
+{
+       int err = 0;
+       u32 ptr32;
+
+       if (!access_ok(VERIFY_READ, from, sizeof(compat_siginfo_t)))
+               return -EFAULT;
+
+       get_user_try {
+               get_user_ex(to->si_signo, &from->si_signo);
+               get_user_ex(to->si_errno, &from->si_errno);
+               get_user_ex(to->si_code, &from->si_code);
+
+               get_user_ex(to->si_pid, &from->si_pid);
+               get_user_ex(to->si_uid, &from->si_uid);
+               get_user_ex(ptr32, &from->si_ptr);
+               to->si_ptr = compat_ptr(ptr32);
+       } get_user_catch(err);
+
+       return err;
+}