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

Pull force_sig() argument change from Eric Biederman:
 "A source of error over the years has been that force_sig has taken a
  task parameter when it is only safe to use force_sig with the current
  task.

  The force_sig function is built for delivering synchronous signals
  such as SIGSEGV where the userspace application caused a synchronous
  fault (such as a page fault) and the kernel responded with a signal.

  Because the name force_sig does not make this clear, and because the
  force_sig takes a task parameter the function force_sig has been
  abused for sending other kinds of signals over the years. Slowly those
  have been fixed when the oopses have been tracked down.

  This set of changes fixes the remaining abusers of force_sig and
  carefully rips out the task parameter from force_sig and friends
  making this kind of error almost impossible in the future"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits)
  signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus
  signal: Remove the signal number and task parameters from force_sig_info
  signal: Factor force_sig_info_to_task out of force_sig_info
  signal: Generate the siginfo in force_sig
  signal: Move the computation of force into send_signal and correct it.
  signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal
  signal: Remove the task parameter from force_sig_fault
  signal: Use force_sig_fault_to_task for the two calls that don't deliver to current
  signal: Explicitly call force_sig_fault on current
  signal/unicore32: Remove tsk parameter from __do_user_fault
  signal/arm: Remove tsk parameter from __do_user_fault
  signal/arm: Remove tsk parameter from ptrace_break
  signal/nds32: Remove tsk parameter from send_sigtrap
  signal/riscv: Remove tsk parameter from do_trap
  signal/sh: Remove tsk parameter from force_sig_info_fault
  signal/um: Remove task parameter from send_sigtrap
  signal/x86: Remove task parameter from send_sigtrap
  signal: Remove task parameter from force_sig_mceerr
  signal: Remove task parameter from force_sig
  signal: Remove task parameter from force_sigsegv
  ...

7 files changed, 14 insertions, 16 deletions

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index f0fbbf6a6a1f..b448b0938299 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -639,7 +639,7 @@ void do_break (struct pt_regs *regs, unsigned long address,
 	hw_breakpoint_disable();
 
 	/* Deliver the signal to userspace */
-	force_sig_fault(SIGTRAP, TRAP_HWBKPT, (void __user *)address, current);
+	force_sig_fault(SIGTRAP, TRAP_HWBKPT, (void __user *)address);
 }
 #endif	/* CONFIG_PPC_ADV_DEBUG_REGS */
 
diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c
index a2b74e057904..f50b708d6d77 100644
--- a/arch/powerpc/kernel/signal_32.c
+++ b/arch/powerpc/kernel/signal_32.c
@@ -1245,7 +1245,7 @@ SYSCALL_DEFINE0(rt_sigreturn)
 				   current->comm, current->pid,
 				   rt_sf, regs->nip, regs->link);
 
-	force_sig(SIGSEGV, current);
+	force_sig(SIGSEGV);
 	return 0;
 }
 
@@ -1334,7 +1334,7 @@ SYSCALL_DEFINE3(debug_setcontext, struct ucontext __user *, ctx,
 					   current->comm, current->pid,
 					   ctx, regs->nip, regs->link);
 
-		force_sig(SIGSEGV, current);
+		force_sig(SIGSEGV);
 		goto out;
 	}
 
@@ -1512,6 +1512,6 @@ badframe:
 				   current->comm, current->pid,
 				   addr, regs->nip, regs->link);
 
-	force_sig(SIGSEGV, current);
+	force_sig(SIGSEGV);
 	return 0;
 }
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index 4292ea39baa4..2f80e270c7b0 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -808,7 +808,7 @@ badframe:
 				   current->comm, current->pid, "rt_sigreturn",
 				   (long)uc, regs->nip, regs->link);
 
-	force_sig(SIGSEGV, current);
+	force_sig(SIGSEGV);
 	return 0;
 }
 
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 47df30982de1..11caa0291254 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -297,7 +297,7 @@ NOKPROBE_SYMBOL(die);
 
 void user_single_step_report(struct pt_regs *regs)
 {
-	force_sig_fault(SIGTRAP, TRAP_TRACE, (void __user *)regs->nip, current);
+	force_sig_fault(SIGTRAP, TRAP_TRACE, (void __user *)regs->nip);
 }
 
 static void show_signal_msg(int signr, struct pt_regs *regs, int code,
@@ -363,7 +363,7 @@ void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
 	if (!exception_common(signr, regs, code, addr))
 		return;
 
-	force_sig_fault(signr, code, (void __user *)addr, current);
+	force_sig_fault(signr, code, (void __user *)addr);
 }
 
 /*
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index ec6b7ad70659..d989592b6fc8 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -178,13 +178,12 @@ static int do_sigbus(struct pt_regs *regs, unsigned long address,
 		if (fault & VM_FAULT_HWPOISON)
 			lsb = PAGE_SHIFT;
 
-		force_sig_mceerr(BUS_MCEERR_AR, (void __user *)address, lsb,
-				 current);
+		force_sig_mceerr(BUS_MCEERR_AR, (void __user *)address, lsb);
 		return 0;
 	}
 
 #endif
-	force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)address, current);
+	force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)address);
 	return 0;
 }
 
diff --git a/arch/powerpc/platforms/cell/spufs/fault.c b/arch/powerpc/platforms/cell/spufs/fault.c
index 6dfd2cb1bce7..24adbe3c605c 100644
--- a/arch/powerpc/platforms/cell/spufs/fault.c
+++ b/arch/powerpc/platforms/cell/spufs/fault.c
@@ -31,22 +31,21 @@ static void spufs_handle_event(struct spu_context *ctx,
 
 	switch (type) {
 	case SPE_EVENT_INVALID_DMA:
-		force_sig_fault(SIGBUS, BUS_OBJERR, NULL, current);
+		force_sig_fault(SIGBUS, BUS_OBJERR, NULL);
 		break;
 	case SPE_EVENT_SPE_DATA_STORAGE:
 		ctx->ops->restart_dma(ctx);
-		force_sig_fault(SIGSEGV, SEGV_ACCERR, (void __user *)ea,
-				current);
+		force_sig_fault(SIGSEGV, SEGV_ACCERR, (void __user *)ea);
 		break;
 	case SPE_EVENT_DMA_ALIGNMENT:
 		/* DAR isn't set for an alignment fault :( */
-		force_sig_fault(SIGBUS, BUS_ADRALN, NULL, current);
+		force_sig_fault(SIGBUS, BUS_ADRALN, NULL);
 		break;
 	case SPE_EVENT_SPE_ERROR:
 		force_sig_fault(
 			SIGILL, ILL_ILLOPC,
 			(void __user *)(unsigned long)
-			ctx->ops->npc_read(ctx) - 4, current);
+			ctx->ops->npc_read(ctx) - 4);
 		break;
 	}
 }
diff --git a/arch/powerpc/platforms/cell/spufs/run.c b/arch/powerpc/platforms/cell/spufs/run.c
index 07f82d7395ff..3f2380f40f99 100644
--- a/arch/powerpc/platforms/cell/spufs/run.c
+++ b/arch/powerpc/platforms/cell/spufs/run.c
@@ -443,7 +443,7 @@ long spufs_run_spu(struct spu_context *ctx, u32 *npc, u32 *event)
 
 	else if (unlikely((status & SPU_STATUS_STOPPED_BY_STOP)
 	    && (status >> SPU_STOP_STATUS_SHIFT) == 0x3fff)) {
-		force_sig(SIGTRAP, current);
+		force_sig(SIGTRAP);
 		ret = -ERESTARTSYS;
 	}