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
  ...

10 files changed, 38 insertions, 41 deletions

diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c
index 59eaf6227af1..4282116e28e7 100644
--- a/arch/sparc/kernel/process_64.c
+++ b/arch/sparc/kernel/process_64.c
@@ -519,7 +519,7 @@ void synchronize_user_stack(void)
 
 static void stack_unaligned(unsigned long sp)
 {
-	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) sp, 0, current);
+	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) sp, 0);
 }
 
 static const char uwfault32[] = KERN_INFO \
@@ -570,7 +570,7 @@ void fault_in_user_windows(struct pt_regs *regs)
 
 barf:
 	set_thread_wsaved(window + 1);
-	force_sig(SIGSEGV, current);
+	force_sig(SIGSEGV);
 }
 
 asmlinkage long sparc_do_fork(unsigned long clone_flags,
diff --git a/arch/sparc/kernel/signal32.c b/arch/sparc/kernel/signal32.c
index e800ce13cc6e..a237810aa9f4 100644
--- a/arch/sparc/kernel/signal32.c
+++ b/arch/sparc/kernel/signal32.c
@@ -170,7 +170,7 @@ void do_sigreturn32(struct pt_regs *regs)
 	return;
 
 segv:
-	force_sig(SIGSEGV, current);
+	force_sig(SIGSEGV);
 }
 
 asmlinkage void do_rt_sigreturn32(struct pt_regs *regs)
@@ -256,7 +256,7 @@ asmlinkage void do_rt_sigreturn32(struct pt_regs *regs)
 	set_current_blocked(&set);
 	return;
 segv:
-	force_sig(SIGSEGV, current);
+	force_sig(SIGSEGV);
 }
 
 static void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
@@ -375,7 +375,7 @@ static int setup_frame32(struct ksignal *ksig, struct pt_regs *regs,
 			pr_info("%s[%d] bad frame in setup_frame32: %08lx TPC %08lx O7 %08lx\n",
 				current->comm, current->pid, (unsigned long)sf,
 				regs->tpc, regs->u_regs[UREG_I7]);
-		force_sigsegv(ksig->sig, current);
+		force_sigsegv(ksig->sig);
 		return -EINVAL;
 	}
 
@@ -509,7 +509,7 @@ static int setup_rt_frame32(struct ksignal *ksig, struct pt_regs *regs,
 			pr_info("%s[%d] bad frame in setup_rt_frame32: %08lx TPC %08lx O7 %08lx\n",
 				current->comm, current->pid, (unsigned long)sf,
 				regs->tpc, regs->u_regs[UREG_I7]);
-		force_sigsegv(ksig->sig, current);
+		force_sigsegv(ksig->sig);
 		return -EINVAL;
 	}
 
diff --git a/arch/sparc/kernel/signal_32.c b/arch/sparc/kernel/signal_32.c
index 83953780ca01..42c3de313fd6 100644
--- a/arch/sparc/kernel/signal_32.c
+++ b/arch/sparc/kernel/signal_32.c
@@ -137,7 +137,7 @@ asmlinkage void do_sigreturn(struct pt_regs *regs)
 	return;
 
 segv_and_exit:
-	force_sig(SIGSEGV, current);
+	force_sig(SIGSEGV);
 }
 
 asmlinkage void do_rt_sigreturn(struct pt_regs *regs)
@@ -196,7 +196,7 @@ asmlinkage void do_rt_sigreturn(struct pt_regs *regs)
 	set_current_blocked(&set);
 	return;
 segv:
-	force_sig(SIGSEGV, current);
+	force_sig(SIGSEGV);
 }
 
 static inline void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c
index ca70787efd8e..69ae814b7e90 100644
--- a/arch/sparc/kernel/signal_64.c
+++ b/arch/sparc/kernel/signal_64.c
@@ -134,7 +134,7 @@ out:
 	exception_exit(prev_state);
 	return;
 do_sigsegv:
-	force_sig(SIGSEGV, current);
+	force_sig(SIGSEGV);
 	goto out;
 }
 
@@ -228,7 +228,7 @@ out:
 	exception_exit(prev_state);
 	return;
 do_sigsegv:
-	force_sig(SIGSEGV, current);
+	force_sig(SIGSEGV);
 	goto out;
 }
 
@@ -320,7 +320,7 @@ void do_rt_sigreturn(struct pt_regs *regs)
 	set_current_blocked(&set);
 	return;
 segv:
-	force_sig(SIGSEGV, current);
+	force_sig(SIGSEGV);
 }
 
 static inline void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
@@ -374,7 +374,7 @@ setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
 			pr_info("%s[%d] bad frame in setup_rt_frame: %016lx TPC %016lx O7 %016lx\n",
 				current->comm, current->pid, (unsigned long)sf,
 				regs->tpc, regs->u_regs[UREG_I7]);
-		force_sigsegv(ksig->sig, current);
+		force_sigsegv(ksig->sig);
 		return -EINVAL;
 	}
 
diff --git a/arch/sparc/kernel/sys_sparc_32.c b/arch/sparc/kernel/sys_sparc_32.c
index 452e4d080855..be77538bc038 100644
--- a/arch/sparc/kernel/sys_sparc_32.c
+++ b/arch/sparc/kernel/sys_sparc_32.c
@@ -151,7 +151,7 @@ sparc_breakpoint (struct pt_regs *regs)
 #ifdef DEBUG_SPARC_BREAKPOINT
         printk ("TRAP: Entering kernel PC=%x, nPC=%x\n", regs->pc, regs->npc);
 #endif
-	force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc, 0, current);
+	force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc, 0);
 
 #ifdef DEBUG_SPARC_BREAKPOINT
 	printk ("TRAP: Returning to space: PC=%x nPC=%x\n", regs->pc, regs->npc);
diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c
index 9825ca6a6020..ccc88926bc00 100644
--- a/arch/sparc/kernel/sys_sparc_64.c
+++ b/arch/sparc/kernel/sys_sparc_64.c
@@ -511,7 +511,7 @@ asmlinkage void sparc_breakpoint(struct pt_regs *regs)
 #ifdef DEBUG_SPARC_BREAKPOINT
         printk ("TRAP: Entering kernel PC=%lx, nPC=%lx\n", regs->tpc, regs->tnpc);
 #endif
-	force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->tpc, 0, current);
+	force_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->tpc, 0);
 #ifdef DEBUG_SPARC_BREAKPOINT
 	printk ("TRAP: Returning to space: PC=%lx nPC=%lx\n", regs->tpc, regs->tnpc);
 #endif
diff --git a/arch/sparc/kernel/traps_32.c b/arch/sparc/kernel/traps_32.c
index bcdfc6168dd5..4ceecad556a9 100644
--- a/arch/sparc/kernel/traps_32.c
+++ b/arch/sparc/kernel/traps_32.c
@@ -103,7 +103,7 @@ void do_hw_interrupt(struct pt_regs *regs, unsigned long type)
 		die_if_kernel("Kernel bad trap", regs);
 
 	force_sig_fault(SIGILL, ILL_ILLTRP,
-			(void __user *)regs->pc, type - 0x80, current);
+			(void __user *)regs->pc, type - 0x80);
 }
 
 void do_illegal_instruction(struct pt_regs *regs, unsigned long pc, unsigned long npc,
@@ -327,7 +327,7 @@ void handle_reg_access(struct pt_regs *regs, unsigned long pc, unsigned long npc
 	printk("Register Access Exception at PC %08lx NPC %08lx PSR %08lx\n",
 	       pc, npc, psr);
 #endif
-	force_sig_fault(SIGBUS, BUS_OBJERR, (void __user *)pc, 0, current);
+	force_sig_fault(SIGBUS, BUS_OBJERR, (void __user *)pc, 0);
 }
 
 void handle_cp_disabled(struct pt_regs *regs, unsigned long pc, unsigned long npc,
diff --git a/arch/sparc/kernel/traps_64.c b/arch/sparc/kernel/traps_64.c
index 04aa588d5dd1..27778b65a965 100644
--- a/arch/sparc/kernel/traps_64.c
+++ b/arch/sparc/kernel/traps_64.c
@@ -108,7 +108,7 @@ void bad_trap(struct pt_regs *regs, long lvl)
 		regs->tnpc &= 0xffffffff;
 	}
 	force_sig_fault(SIGILL, ILL_ILLTRP,
-			(void __user *)regs->tpc, lvl, current);
+			(void __user *)regs->tpc, lvl);
 }
 
 void bad_trap_tl1(struct pt_regs *regs, long lvl)
@@ -202,7 +202,7 @@ void spitfire_insn_access_exception(struct pt_regs *regs, unsigned long sfsr, un
 		regs->tnpc &= 0xffffffff;
 	}
 	force_sig_fault(SIGSEGV, SEGV_MAPERR,
-			(void __user *)regs->tpc, 0, current);
+			(void __user *)regs->tpc, 0);
 out:
 	exception_exit(prev_state);
 }
@@ -237,7 +237,7 @@ void sun4v_insn_access_exception(struct pt_regs *regs, unsigned long addr, unsig
 		regs->tpc &= 0xffffffff;
 		regs->tnpc &= 0xffffffff;
 	}
-	force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *) addr, 0, current);
+	force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *) addr, 0);
 }
 
 void sun4v_insn_access_exception_tl1(struct pt_regs *regs, unsigned long addr, unsigned long type_ctx)
@@ -322,7 +322,7 @@ void spitfire_data_access_exception(struct pt_regs *regs, unsigned long sfsr, un
 	if (is_no_fault_exception(regs))
 		return;
 
-	force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *)sfar, 0, current);
+	force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *)sfar, 0);
 out:
 	exception_exit(prev_state);
 }
@@ -386,16 +386,13 @@ void sun4v_data_access_exception(struct pt_regs *regs, unsigned long addr, unsig
 	 */
 	switch (type) {
 	case HV_FAULT_TYPE_INV_ASI:
-		force_sig_fault(SIGILL, ILL_ILLADR, (void __user *)addr, 0,
-				current);
+		force_sig_fault(SIGILL, ILL_ILLADR, (void __user *)addr, 0);
 		break;
 	case HV_FAULT_TYPE_MCD_DIS:
-		force_sig_fault(SIGSEGV, SEGV_ACCADI, (void __user *)addr, 0,
-				current);
+		force_sig_fault(SIGSEGV, SEGV_ACCADI, (void __user *)addr, 0);
 		break;
 	default:
-		force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *)addr, 0,
-				current);
+		force_sig_fault(SIGSEGV, SEGV_MAPERR, (void __user *)addr, 0);
 		break;
 	}
 }
@@ -572,7 +569,7 @@ static void spitfire_ue_log(unsigned long afsr, unsigned long afar, unsigned lon
 		regs->tpc &= 0xffffffff;
 		regs->tnpc &= 0xffffffff;
 	}
-	force_sig_fault(SIGBUS, BUS_OBJERR, (void *)0, 0, current);
+	force_sig_fault(SIGBUS, BUS_OBJERR, (void *)0, 0);
 }
 
 void spitfire_access_error(struct pt_regs *regs, unsigned long status_encoded, unsigned long afar)
@@ -2074,7 +2071,7 @@ void do_mcd_err(struct pt_regs *regs, struct sun4v_error_entry ent)
 	 * code
 	 */
 	force_sig_fault(SIGSEGV, SEGV_ADIDERR, (void __user *)ent.err_raddr,
-			0, current);
+			0);
 }
 
 /* We run with %pil set to PIL_NORMAL_MAX and PSTATE_IE enabled in %pstate.
@@ -2182,13 +2179,13 @@ bool sun4v_nonresum_error_user_handled(struct pt_regs *regs,
 				addr += PAGE_SIZE;
 			}
 		}
-		force_sig(SIGKILL, current);
+		force_sig(SIGKILL);
 
 		return true;
 	}
 	if (attrs & SUN4V_ERR_ATTRS_PIO) {
 		force_sig_fault(SIGBUS, BUS_ADRERR,
-				(void __user *)sun4v_get_vaddr(regs), 0, current);
+				(void __user *)sun4v_get_vaddr(regs), 0);
 		return true;
 	}
 
@@ -2345,7 +2342,7 @@ static void do_fpe_common(struct pt_regs *regs)
 				code = FPE_FLTRES;
 		}
 		force_sig_fault(SIGFPE, code,
-				(void __user *)regs->tpc, 0, current);
+				(void __user *)regs->tpc, 0);
 	}
 }
 
@@ -2400,7 +2397,7 @@ void do_tof(struct pt_regs *regs)
 		regs->tnpc &= 0xffffffff;
 	}
 	force_sig_fault(SIGEMT, EMT_TAGOVF,
-			(void __user *)regs->tpc, 0, current);
+			(void __user *)regs->tpc, 0);
 out:
 	exception_exit(prev_state);
 }
@@ -2420,7 +2417,7 @@ void do_div0(struct pt_regs *regs)
 		regs->tnpc &= 0xffffffff;
 	}
 	force_sig_fault(SIGFPE, FPE_INTDIV,
-			(void __user *)regs->tpc, 0, current);
+			(void __user *)regs->tpc, 0);
 out:
 	exception_exit(prev_state);
 }
@@ -2616,7 +2613,7 @@ void do_illegal_instruction(struct pt_regs *regs)
 			}
 		}
 	}
-	force_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)pc, 0, current);
+	force_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)pc, 0);
 out:
 	exception_exit(prev_state);
 }
@@ -2636,7 +2633,7 @@ void mem_address_unaligned(struct pt_regs *regs, unsigned long sfar, unsigned lo
 	if (is_no_fault_exception(regs))
 		return;
 
-	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *)sfar, 0, current);
+	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *)sfar, 0);
 out:
 	exception_exit(prev_state);
 }
@@ -2654,7 +2651,7 @@ void sun4v_do_mna(struct pt_regs *regs, unsigned long addr, unsigned long type_c
 	if (is_no_fault_exception(regs))
 		return;
 
-	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) addr, 0, current);
+	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) addr, 0);
 }
 
 /* sun4v_mem_corrupt_detect_precise() - Handle precise exception on an ADI
@@ -2701,7 +2698,7 @@ void sun4v_mem_corrupt_detect_precise(struct pt_regs *regs, unsigned long addr,
 		regs->tpc &= 0xffffffff;
 		regs->tnpc &= 0xffffffff;
 	}
-	force_sig_fault(SIGSEGV, SEGV_ADIPERR, (void __user *)addr, 0, current);
+	force_sig_fault(SIGSEGV, SEGV_ADIPERR, (void __user *)addr, 0);
 }
 
 void do_privop(struct pt_regs *regs)
@@ -2717,7 +2714,7 @@ void do_privop(struct pt_regs *regs)
 		regs->tnpc &= 0xffffffff;
 	}
 	force_sig_fault(SIGILL, ILL_PRVOPC,
-			(void __user *)regs->tpc, 0, current);
+			(void __user *)regs->tpc, 0);
 out:
 	exception_exit(prev_state);
 }
diff --git a/arch/sparc/mm/fault_32.c b/arch/sparc/mm/fault_32.c
index b0440b0edd97..8d69de111470 100644
--- a/arch/sparc/mm/fault_32.c
+++ b/arch/sparc/mm/fault_32.c
@@ -131,7 +131,7 @@ static void __do_fault_siginfo(int code, int sig, struct pt_regs *regs,
 		show_signal_msg(regs, sig, code,
 				addr, current);
 
-	force_sig_fault(sig, code, (void __user *) addr, 0, current);
+	force_sig_fault(sig, code, (void __user *) addr, 0);
 }
 
 static unsigned long compute_si_addr(struct pt_regs *regs, int text_fault)
@@ -425,7 +425,7 @@ do_sigbus:
 static void check_stack_aligned(unsigned long sp)
 {
 	if (sp & 0x7UL)
-		force_sig(SIGILL, current);
+		force_sig(SIGILL);
 }
 
 void window_overflow_fault(void)
diff --git a/arch/sparc/mm/fault_64.c b/arch/sparc/mm/fault_64.c
index 8f8a604c1300..83fda4d9c3b2 100644
--- a/arch/sparc/mm/fault_64.c
+++ b/arch/sparc/mm/fault_64.c
@@ -187,7 +187,7 @@ static void do_fault_siginfo(int code, int sig, struct pt_regs *regs,
 	if (unlikely(show_unhandled_signals))
 		show_signal_msg(regs, sig, code, addr, current);
 
-	force_sig_fault(sig, code, (void __user *) addr, 0, current);
+	force_sig_fault(sig, code, (void __user *) addr, 0);
 }
 
 static unsigned int get_fault_insn(struct pt_regs *regs, unsigned int insn)