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

copy_siginfo_to_user32() and copy_siginfo_from_user32() are used
by both the 32-bit compat and x32 ABIs.  Move them to
signal_compat.c.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1434974121-32575-2-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c
index ae3a29ae875b5508d62b4d91c79db3f1dc26581d..a0a19b7ba22dc242d2bb957b71aa617e6c75104e 100644 (file)
--- a/arch/x86/ia32/ia32_signal.c
+++ b/arch/x86/ia32/ia32_signal.c
@@ -34,99 +34,6 @@
 #include <asm/sys_ia32.h>
 #include <asm/smap.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;
-}
-
 /*
  * Do a signal return; undo the signal stack.
  */

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 0f15af41bd80b764c80f90f0153a96e136a2106e..dc19730ad0dbb58a799d71fb71d02e1f9e5ed3aa 100644 (file)
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -23,6 +23,7 @@ KASAN_SANITIZE_dumpstack_$(BITS).o := n
 CFLAGS_irq.o := -I$(src)/../include/asm/trace
 
 obj-y                  := process_$(BITS).o signal.o
+obj-$(CONFIG_COMPAT)   += signal_compat.o
 obj-y                  += traps.o irq.o irq_$(BITS).o dumpstack_$(BITS).o
 obj-y                  += time.o ioport.o ldt.o dumpstack.o nmi.o
 obj-y                  += setup.o x86_init.o i8259.o irqinit.o jump_label.o

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;
+}