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
  ...

3 files changed, 11 insertions, 8 deletions

diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
index d5084ebd9f03..2a9df80ea887 100644
--- a/include/linux/ptrace.h
+++ b/include/linux/ptrace.h
@@ -355,7 +355,7 @@ static inline void user_single_step_report(struct pt_regs *regs)
 	info.si_code = SI_USER;
 	info.si_pid = 0;
 	info.si_uid = 0;
-	force_sig_info(info.si_signo, &info, current);
+	force_sig_info(&info);
 }
 #endif
 
diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h
index 38a0f0785323..532458698bde 100644
--- a/include/linux/sched/signal.h
+++ b/include/linux/sched/signal.h
@@ -307,16 +307,19 @@ static inline void kernel_signal_stop(void)
 # define ___ARCH_SI_IA64(_a1, _a2, _a3)
 #endif
 
-int force_sig_fault(int sig, int code, void __user *addr
+int force_sig_fault_to_task(int sig, int code, void __user *addr
 	___ARCH_SI_TRAPNO(int trapno)
 	___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr)
 	, struct task_struct *t);
+int force_sig_fault(int sig, int code, void __user *addr
+	___ARCH_SI_TRAPNO(int trapno)
+	___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr));
 int send_sig_fault(int sig, int code, void __user *addr
 	___ARCH_SI_TRAPNO(int trapno)
 	___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr)
 	, struct task_struct *t);
 
-int force_sig_mceerr(int code, void __user *, short, struct task_struct *);
+int force_sig_mceerr(int code, void __user *, short);
 int send_sig_mceerr(int code, void __user *, short, struct task_struct *);
 
 int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper);
@@ -325,17 +328,17 @@ int force_sig_pkuerr(void __user *addr, u32 pkey);
 int force_sig_ptrace_errno_trap(int errno, void __user *addr);
 
 extern int send_sig_info(int, struct kernel_siginfo *, struct task_struct *);
-extern void force_sigsegv(int sig, struct task_struct *p);
-extern int force_sig_info(int, struct kernel_siginfo *, struct task_struct *);
+extern void force_sigsegv(int sig);
+extern int force_sig_info(struct kernel_siginfo *);
 extern int __kill_pgrp_info(int sig, struct kernel_siginfo *info, struct pid *pgrp);
 extern int kill_pid_info(int sig, struct kernel_siginfo *info, struct pid *pid);
-extern int kill_pid_info_as_cred(int, struct kernel_siginfo *, struct pid *,
+extern int kill_pid_usb_asyncio(int sig, int errno, sigval_t addr, struct pid *,
 				const struct cred *);
 extern int kill_pgrp(struct pid *pid, int sig, int priv);
 extern int kill_pid(struct pid *pid, int sig, int priv);
 extern __must_check bool do_notify_parent(struct task_struct *, int);
 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
-extern void force_sig(int, struct task_struct *);
+extern void force_sig(int);
 extern int send_sig(int, struct task_struct *, int);
 extern int zap_other_threads(struct task_struct *p);
 extern struct sigqueue *sigqueue_alloc(void);
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 2bcef4c70183..bc4bbbb9ed9a 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -264,7 +264,7 @@ static inline void addr_limit_user_check(void)
 
 	if (CHECK_DATA_CORRUPTION(!segment_eq(get_fs(), USER_DS),
 				  "Invalid address limit on user-mode return"))
-		force_sig(SIGKILL, current);
+		force_sig(SIGKILL);
 
 #ifdef TIF_FSCHECK
 	clear_thread_flag(TIF_FSCHECK);