Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal

Pull third pile of signal handling patches from Al Viro:
 "This time it's mostly helpers and conversions to them; there's a lot
  of stuff remaining in the tree, but that'll either go in -rc2
  (isolated bug fixes, ideally via arch maintainers' trees) or will sit
  there until the next cycle."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  x86: get rid of calling do_notify_resume() when returning to kernel mode
  blackfin: check __get_user() return value
  whack-a-mole with TIF_FREEZE
  FRV: Optimise the system call exit path in entry.S [ver #2]
  FRV: Shrink TIF_WORK_MASK [ver #2]
  FRV: Prevent syscall exit tracing and notify_resume at end of kernel exceptions
  new helper: signal_delivered()
  powerpc: get rid of restore_sigmask()
  most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from set
  set_restore_sigmask() is never called without SIGPENDING (and never should be)
  TIF_RESTORE_SIGMASK can be set only when TIF_SIGPENDING is set
  don't call try_to_freeze() from do_signal()
  pull clearing RESTORE_SIGMASK into block_sigmask()
  sh64: failure to build sigframe != signal without handler
  openrisc: tracehook_signal_handler() is supposed to be called on success
  new helper: sigmask_to_save()
  new helper: restore_saved_sigmask()
  new helpers: {clear,test,test_and_clear}_restore_sigmask()
  HAVE_RESTORE_SIGMASK is defined on all architectures now

4 files changed, 8 insertions, 35 deletions

diff --git a/arch/mips/kernel/signal-common.h b/arch/mips/kernel/signal-common.h
index 10263b405981..9c60d09e62a7 100644
--- a/arch/mips/kernel/signal-common.h
+++ b/arch/mips/kernel/signal-common.h
@@ -19,8 +19,6 @@
 #  define DEBUGP(fmt, args...)
 #endif
 
-#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
-
 /*
  * Determine which stack to use..
  */
diff --git a/arch/mips/kernel/signal.c b/arch/mips/kernel/signal.c
index 8a6e6d116ab0..f2c09cfc60ac 100644
--- a/arch/mips/kernel/signal.c
+++ b/arch/mips/kernel/signal.c
@@ -339,7 +339,6 @@ asmlinkage void sys_sigreturn(nabi_no_regargs struct pt_regs regs)
         if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked)))
                 goto badframe;
 
-        sigdelsetmask(&blocked, ~_BLOCKABLE);
         set_current_blocked(&blocked);
 
         sig = restore_sigcontext(&regs, &frame->sf_sc);
@@ -375,7 +374,6 @@ asmlinkage void sys_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
         if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
                 goto badframe;
 
-        sigdelsetmask(&set, ~_BLOCKABLE);
         set_current_blocked(&set);
 
         sig = restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext);
@@ -514,9 +512,10 @@ struct mips_abi mips_abi = {
         .restart        = __NR_restart_syscall
 };
 
-static int handle_signal(unsigned long sig, siginfo_t *info,
-        struct k_sigaction *ka, sigset_t *oldset, struct pt_regs *regs)
+static void handle_signal(unsigned long sig, siginfo_t *info,
+        struct k_sigaction *ka, struct pt_regs *regs)
 {
+        sigset_t *oldset = sigmask_to_save();
         int ret;
         struct mips_abi *abi = current->thread.abi;
         void *vdso = current->mm->context.vdso;
@@ -550,17 +549,14 @@ static int handle_signal(unsigned long sig, siginfo_t *info,
                                        ka, regs, sig, oldset);
 
         if (ret)
-                return ret;
-
-        block_sigmask(ka, sig);
+                return;
 
-        return ret;
+        signal_delivered(sig, info, ka, regs, 0);
 }
 
 static void do_signal(struct pt_regs *regs)
 {
         struct k_sigaction ka;
-        sigset_t *oldset;
         siginfo_t info;
         int signr;
 
@@ -572,25 +568,10 @@ static void do_signal(struct pt_regs *regs)
         if (!user_mode(regs))
                 return;
 
-        if (test_thread_flag(TIF_RESTORE_SIGMASK))
-                oldset = &current->saved_sigmask;
-        else
-                oldset = &current->blocked;
-
         signr = get_signal_to_deliver(&info, &ka, regs, NULL);
         if (signr > 0) {
                 /* Whee!  Actually deliver the signal.  */
-                if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
-                        /*
-                         * A signal was successfully delivered; the saved
-                         * sigmask will have been stored in the signal frame,
-                         * and will be restored by sigreturn, so we can simply
-                         * clear the TIF_RESTORE_SIGMASK flag.
-                         */
-                        if (test_thread_flag(TIF_RESTORE_SIGMASK))
-                                clear_thread_flag(TIF_RESTORE_SIGMASK);
-                }
-
+                handle_signal(signr, &info, &ka, regs);
                 return;
         }
 
@@ -614,10 +595,7 @@ static void do_signal(struct pt_regs *regs)
          * If there's no signal to deliver, we just put the saved sigmask
          * back
          */
-        if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
-                clear_thread_flag(TIF_RESTORE_SIGMASK);
-                sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
-        }
+        restore_saved_sigmask();
 }
 
 /*
@@ -630,7 +608,7 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
         local_irq_enable();
 
         /* deal with pending signal delivery */
-        if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
+        if (thread_info_flags & _TIF_SIGPENDING)
                 do_signal(regs);
 
         if (thread_info_flags & _TIF_NOTIFY_RESUME) {
diff --git a/arch/mips/kernel/signal32.c b/arch/mips/kernel/signal32.c
index b4fe2eacbd5d..da1b56a39ac7 100644
--- a/arch/mips/kernel/signal32.c
+++ b/arch/mips/kernel/signal32.c
@@ -465,7 +465,6 @@ asmlinkage void sys32_sigreturn(nabi_no_regargs struct pt_regs regs)
         if (__copy_conv_sigset_from_user(&blocked, &frame->sf_mask))
                 goto badframe;
 
-        sigdelsetmask(&blocked, ~_BLOCKABLE);
         set_current_blocked(&blocked);
 
         sig = restore_sigcontext32(&regs, &frame->sf_sc);
@@ -503,7 +502,6 @@ asmlinkage void sys32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
         if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask))
                 goto badframe;
 
-        sigdelsetmask(&set, ~_BLOCKABLE);
         set_current_blocked(&set);
 
         sig = restore_sigcontext32(&regs, &frame->rs_uc.uc_mcontext);
diff --git a/arch/mips/kernel/signal_n32.c b/arch/mips/kernel/signal_n32.c
index 63ffac9af7c5..3574c145511b 100644
--- a/arch/mips/kernel/signal_n32.c
+++ b/arch/mips/kernel/signal_n32.c
@@ -109,7 +109,6 @@ asmlinkage void sysn32_rt_sigreturn(nabi_no_regargs struct pt_regs regs)
         if (__copy_conv_sigset_from_user(&set, &frame->rs_uc.uc_sigmask))
                 goto badframe;
 
-        sigdelsetmask(&set, ~_BLOCKABLE);
         set_current_blocked(&set);
 
         sig = restore_sigcontext(&regs, &frame->rs_uc.uc_mcontext);