Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

Pull siginfo updates from Eric Biederman:
 "This set of changes close the known issues with setting si_code to an
  invalid value, and with not fully initializing struct siginfo. There
  remains work to do on nds32, arc, unicore32, powerpc, arm, arm64, ia64
  and x86 to get the code that generates siginfo into a simpler and more
  maintainable state. Most of that work involves refactoring the signal
  handling code and thus careful code review.

  Also not included is the work to shrink the in kernel version of
  struct siginfo. That depends on getting the number of places that
  directly manipulate struct siginfo under control, as it requires the
  introduction of struct kernel_siginfo for the in kernel things.

  Overall this set of changes looks like it is making good progress, and
  with a little luck I will be wrapping up the siginfo work next
  development cycle"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits)
  signal/sh: Stop gcc warning about an impossible case in do_divide_error
  signal/mips: Report FPE_FLTUNK for undiagnosed floating point exceptions
  signal/um: More carefully relay signals in relay_signal.
  signal: Extend siginfo_layout with SIL_FAULT_{MCEERR|BNDERR|PKUERR}
  signal: Remove unncessary #ifdef SEGV_PKUERR in 32bit compat code
  signal/signalfd: Add support for SIGSYS
  signal/signalfd: Remove __put_user from signalfd_copyinfo
  signal/xtensa: Use force_sig_fault where appropriate
  signal/xtensa: Consistenly use SIGBUS in do_unaligned_user
  signal/um: Use force_sig_fault where appropriate
  signal/sparc: Use force_sig_fault where appropriate
  signal/sparc: Use send_sig_fault where appropriate
  signal/sh: Use force_sig_fault where appropriate
  signal/s390: Use force_sig_fault where appropriate
  signal/riscv: Replace do_trap_siginfo with force_sig_fault
  signal/riscv: Use force_sig_fault where appropriate
  signal/parisc: Use force_sig_fault where appropriate
  signal/parisc: Use force_sig_mceerr where appropriate
  signal/openrisc: Use force_sig_fault where appropriate
  signal/nios2: Use force_sig_fault where appropriate
  ...

1 files changed, 52 insertions, 129 deletions

diff --git a/kernel/signal.c b/kernel/signal.c
index 9c33163a6165..0f865d67415d 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1539,7 +1539,6 @@ int send_sig_fault(int sig, int code, void __user *addr
 	return send_sig_info(info.si_signo, &info, t);
 }
 
-#if defined(BUS_MCEERR_AO) && defined(BUS_MCEERR_AR)
 int force_sig_mceerr(int code, void __user *addr, short lsb, struct task_struct *t)
 {
 	struct siginfo info;
@@ -1568,9 +1567,7 @@ int send_sig_mceerr(int code, void __user *addr, short lsb, struct task_struct *
 	return send_sig_info(info.si_signo, &info, t);
 }
 EXPORT_SYMBOL(send_sig_mceerr);
-#endif
 
-#ifdef SEGV_BNDERR
 int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper)
 {
 	struct siginfo info;
@@ -1584,7 +1581,6 @@ int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper)
 	info.si_upper = upper;
 	return force_sig_info(info.si_signo, &info, current);
 }
-#endif
 
 #ifdef SEGV_PKUERR
 int force_sig_pkuerr(void __user *addr, u32 pkey)
@@ -2837,8 +2833,19 @@ enum siginfo_layout siginfo_layout(int sig, int si_code)
 			[SIGPOLL] = { NSIGPOLL, SIL_POLL },
 			[SIGSYS]  = { NSIGSYS,  SIL_SYS },
 		};
-		if ((sig < ARRAY_SIZE(filter)) && (si_code <= filter[sig].limit))
+		if ((sig < ARRAY_SIZE(filter)) && (si_code <= filter[sig].limit)) {
 			layout = filter[sig].layout;
+			/* Handle the exceptions */
+			if ((sig == SIGBUS) &&
+			    (si_code >= BUS_MCEERR_AR) && (si_code <= BUS_MCEERR_AO))
+				layout = SIL_FAULT_MCEERR;
+			else if ((sig == SIGSEGV) && (si_code == SEGV_BNDERR))
+				layout = SIL_FAULT_BNDERR;
+#ifdef SEGV_PKUERR
+			else if ((sig == SIGSEGV) && (si_code == SEGV_PKUERR))
+				layout = SIL_FAULT_PKUERR;
+#endif
+		}
 		else if (si_code <= NSIGPOLL)
 			layout = SIL_POLL;
 	} else {
@@ -2848,104 +2855,15 @@ enum siginfo_layout siginfo_layout(int sig, int si_code)
 			layout = SIL_POLL;
 		else if (si_code < 0)
 			layout = SIL_RT;
-		/* Tests to support buggy kernel ABIs */
-#ifdef TRAP_FIXME
-		if ((sig == SIGTRAP) && (si_code == TRAP_FIXME))
-			layout = SIL_FAULT;
-#endif
-#ifdef FPE_FIXME
-		if ((sig == SIGFPE) && (si_code == FPE_FIXME))
-			layout = SIL_FAULT;
-#endif
 	}
 	return layout;
 }
 
 int copy_siginfo_to_user(siginfo_t __user *to, const siginfo_t *from)
 {
-	int err;
-
-	if (!access_ok (VERIFY_WRITE, to, sizeof(siginfo_t)))
+	if (copy_to_user(to, from , sizeof(struct siginfo)))
 		return -EFAULT;
-	if (from->si_code < 0)
-		return __copy_to_user(to, from, sizeof(siginfo_t))
-			? -EFAULT : 0;
-	/*
-	 * If you change siginfo_t structure, please be sure
-	 * this code is fixed accordingly.
-	 * Please remember to update the signalfd_copyinfo() function
-	 * inside fs/signalfd.c too, in case siginfo_t changes.
-	 * 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.
-	 */
-	err = __put_user(from->si_signo, &to->si_signo);
-	err |= __put_user(from->si_errno, &to->si_errno);
-	err |= __put_user(from->si_code, &to->si_code);
-	switch (siginfo_layout(from->si_signo, from->si_code)) {
-	case SIL_KILL:
-		err |= __put_user(from->si_pid, &to->si_pid);
-		err |= __put_user(from->si_uid, &to->si_uid);
-		break;
-	case SIL_TIMER:
-		/* Unreached SI_TIMER is negative */
-		break;
-	case SIL_POLL:
-		err |= __put_user(from->si_band, &to->si_band);
-		err |= __put_user(from->si_fd, &to->si_fd);
-		break;
-	case SIL_FAULT:
-		err |= __put_user(from->si_addr, &to->si_addr);
-#ifdef __ARCH_SI_TRAPNO
-		err |= __put_user(from->si_trapno, &to->si_trapno);
-#endif
-#ifdef __ia64__
-		err |= __put_user(from->si_imm, &to->si_imm);
-		err |= __put_user(from->si_flags, &to->si_flags);
-		err |= __put_user(from->si_isr, &to->si_isr);
-#endif
-		/*
-		 * Other callers might not initialize the si_lsb field,
-		 * so check explicitly for the right codes here.
-		 */
-#ifdef BUS_MCEERR_AR
-		if (from->si_signo == SIGBUS && from->si_code == BUS_MCEERR_AR)
-			err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb);
-#endif
-#ifdef BUS_MCEERR_AO
-		if (from->si_signo == SIGBUS && from->si_code == BUS_MCEERR_AO)
-			err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb);
-#endif
-#ifdef SEGV_BNDERR
-		if (from->si_signo == SIGSEGV && from->si_code == SEGV_BNDERR) {
-			err |= __put_user(from->si_lower, &to->si_lower);
-			err |= __put_user(from->si_upper, &to->si_upper);
-		}
-#endif
-#ifdef SEGV_PKUERR
-		if (from->si_signo == SIGSEGV && from->si_code == SEGV_PKUERR)
-			err |= __put_user(from->si_pkey, &to->si_pkey);
-#endif
-		break;
-	case SIL_CHLD:
-		err |= __put_user(from->si_pid, &to->si_pid);
-		err |= __put_user(from->si_uid, &to->si_uid);
-		err |= __put_user(from->si_status, &to->si_status);
-		err |= __put_user(from->si_utime, &to->si_utime);
-		err |= __put_user(from->si_stime, &to->si_stime);
-		break;
-	case SIL_RT:
-		err |= __put_user(from->si_pid, &to->si_pid);
-		err |= __put_user(from->si_uid, &to->si_uid);
-		err |= __put_user(from->si_ptr, &to->si_ptr);
-		break;
-	case SIL_SYS:
-		err |= __put_user(from->si_call_addr, &to->si_call_addr);
-		err |= __put_user(from->si_syscall, &to->si_syscall);
-		err |= __put_user(from->si_arch, &to->si_arch);
-		break;
-	}
-	return err;
+	return 0;
 }
 
 #ifdef CONFIG_COMPAT
@@ -2984,27 +2902,28 @@ int __copy_siginfo_to_user32(struct compat_siginfo __user *to,
 #ifdef __ARCH_SI_TRAPNO
 		new.si_trapno = from->si_trapno;
 #endif
-#ifdef BUS_MCEERR_AR
-		if ((from->si_signo == SIGBUS) && (from->si_code == BUS_MCEERR_AR))
-			new.si_addr_lsb = from->si_addr_lsb;
-#endif
-#ifdef BUS_MCEERR_AO
-		if ((from->si_signo == SIGBUS) && (from->si_code == BUS_MCEERR_AO))
-			new.si_addr_lsb = from->si_addr_lsb;
+		break;
+	case SIL_FAULT_MCEERR:
+		new.si_addr = ptr_to_compat(from->si_addr);
+#ifdef __ARCH_SI_TRAPNO
+		new.si_trapno = from->si_trapno;
 #endif
-#ifdef SEGV_BNDERR
-		if ((from->si_signo == SIGSEGV) &&
-		    (from->si_code == SEGV_BNDERR)) {
-			new.si_lower = ptr_to_compat(from->si_lower);
-			new.si_upper = ptr_to_compat(from->si_upper);
-		}
+		new.si_addr_lsb = from->si_addr_lsb;
+		break;
+	case SIL_FAULT_BNDERR:
+		new.si_addr = ptr_to_compat(from->si_addr);
+#ifdef __ARCH_SI_TRAPNO
+		new.si_trapno = from->si_trapno;
 #endif
-#ifdef SEGV_PKUERR
-		if ((from->si_signo == SIGSEGV) &&
-		    (from->si_code == SEGV_PKUERR))
-			new.si_pkey = from->si_pkey;
+		new.si_lower = ptr_to_compat(from->si_lower);
+		new.si_upper = ptr_to_compat(from->si_upper);
+		break;
+	case SIL_FAULT_PKUERR:
+		new.si_addr = ptr_to_compat(from->si_addr);
+#ifdef __ARCH_SI_TRAPNO
+		new.si_trapno = from->si_trapno;
 #endif
-
+		new.si_pkey = from->si_pkey;
 		break;
 	case SIL_CHLD:
 		new.si_pid    = from->si_pid;
@@ -3070,24 +2989,28 @@ int copy_siginfo_from_user32(struct siginfo *to,
 #ifdef __ARCH_SI_TRAPNO
 		to->si_trapno = from.si_trapno;
 #endif
-#ifdef BUS_MCEERR_AR
-		if ((from.si_signo == SIGBUS) && (from.si_code == BUS_MCEERR_AR))
-			to->si_addr_lsb = from.si_addr_lsb;
-#endif
-#ifdef BUS_MCEER_AO
-		if ((from.si_signo == SIGBUS) && (from.si_code == BUS_MCEERR_AO))
-			to->si_addr_lsb = from.si_addr_lsb;
+		break;
+	case SIL_FAULT_MCEERR:
+		to->si_addr = compat_ptr(from.si_addr);
+#ifdef __ARCH_SI_TRAPNO
+		to->si_trapno = from.si_trapno;
 #endif
-#ifdef SEGV_BNDERR
-		if ((from.si_signo == SIGSEGV) && (from.si_code == SEGV_BNDERR)) {
-			to->si_lower = compat_ptr(from.si_lower);
-			to->si_upper = compat_ptr(from.si_upper);
-		}
+		to->si_addr_lsb = from.si_addr_lsb;
+		break;
+	case SIL_FAULT_BNDERR:
+		to->si_addr = compat_ptr(from.si_addr);
+#ifdef __ARCH_SI_TRAPNO
+		to->si_trapno = from.si_trapno;
 #endif
-#ifdef SEGV_PKUERR
-		if ((from.si_signo == SIGSEGV) && (from.si_code == SEGV_PKUERR))
-			to->si_pkey = from.si_pkey;
+		to->si_lower = compat_ptr(from.si_lower);
+		to->si_upper = compat_ptr(from.si_upper);
+		break;
+	case SIL_FAULT_PKUERR:
+		to->si_addr = compat_ptr(from.si_addr);
+#ifdef __ARCH_SI_TRAPNO
+		to->si_trapno = from.si_trapno;
 #endif
+		to->si_pkey = from.si_pkey;
 		break;
 	case SIL_CHLD:
 		to->si_pid    = from.si_pid;