diff mbox series

[5/6] signal/alpha: si_trapno is only used with SIGFPE and SIGTRAP TRAP_UNK

Message ID 87h7gvxx7l.fsf_-_@disp2133
State New
Headers show
Series Final si_trapno bits | expand

Commit Message

Eric W. Biederman July 15, 2021, 6:12 p.m. UTC
While reviewing the signal handlers on alpha it became clear that
si_trapno is only set to a non-zero value when sending SIGFPE and when
sending SITGRAP with si_code TRAP_UNK.

Add send_sig_fault_trapno and send SIGTRAP TRAP_UNK, and SIGFPE with it.

Remove the define of __ARCH_SI_TRAPNO and remove the always zero
si_trapno parameter from send_sig_fault and force_sig_fault.

v1: https://lkml.kernel.org/r/m1eeers7q7.fsf_-_@fess.ebiederm.org
v2: https://lkml.kernel.org/r/20210505141101.11519-7-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/alpha/include/uapi/asm/siginfo.h |  2 --
 arch/alpha/kernel/osf_sys.c           |  2 +-
 arch/alpha/kernel/signal.c            |  4 ++--
 arch/alpha/kernel/traps.c             | 26 +++++++++++++-------------
 arch/alpha/mm/fault.c                 |  4 ++--
 include/linux/sched/signal.h          |  2 ++
 kernel/signal.c                       | 21 +++++++++++++++++++++
 7 files changed, 41 insertions(+), 20 deletions(-)

Comments

Marco Elver July 16, 2021, 11:48 a.m. UTC | #1
On Thu, 15 Jul 2021 at 20:13, Eric W. Biederman <ebiederm@xmission.com> wrote:
> While reviewing the signal handlers on alpha it became clear that
> si_trapno is only set to a non-zero value when sending SIGFPE and when
> sending SITGRAP with si_code TRAP_UNK.
>
> Add send_sig_fault_trapno and send SIGTRAP TRAP_UNK, and SIGFPE with it.
>
> Remove the define of __ARCH_SI_TRAPNO and remove the always zero
> si_trapno parameter from send_sig_fault and force_sig_fault.
>
> v1: https://lkml.kernel.org/r/m1eeers7q7.fsf_-_@fess.ebiederm.org
> v2: https://lkml.kernel.org/r/20210505141101.11519-7-ebiederm@xmission.com
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Reviewed-by: Marco Elver <elver@google.com>

> ---
>  arch/alpha/include/uapi/asm/siginfo.h |  2 --
>  arch/alpha/kernel/osf_sys.c           |  2 +-
>  arch/alpha/kernel/signal.c            |  4 ++--
>  arch/alpha/kernel/traps.c             | 26 +++++++++++++-------------
>  arch/alpha/mm/fault.c                 |  4 ++--
>  include/linux/sched/signal.h          |  2 ++
>  kernel/signal.c                       | 21 +++++++++++++++++++++
>  7 files changed, 41 insertions(+), 20 deletions(-)
>
> diff --git a/arch/alpha/include/uapi/asm/siginfo.h b/arch/alpha/include/uapi/asm/siginfo.h
> index 6e1a2af2f962..e08eae88182b 100644
> --- a/arch/alpha/include/uapi/asm/siginfo.h
> +++ b/arch/alpha/include/uapi/asm/siginfo.h
> @@ -2,8 +2,6 @@
>  #ifndef _ALPHA_SIGINFO_H
>  #define _ALPHA_SIGINFO_H
>
> -#define __ARCH_SI_TRAPNO
> -
>  #include <asm-generic/siginfo.h>
>
>  #endif
> diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c
> index d5367a1c6300..bbdb1a9a5fd8 100644
> --- a/arch/alpha/kernel/osf_sys.c
> +++ b/arch/alpha/kernel/osf_sys.c
> @@ -876,7 +876,7 @@ SYSCALL_DEFINE5(osf_setsysinfo, unsigned long, op, void __user *, buffer,
>                         if (fex & IEEE_TRAP_ENABLE_DZE) si_code = FPE_FLTDIV;
>                         if (fex & IEEE_TRAP_ENABLE_INV) si_code = FPE_FLTINV;
>
> -                       send_sig_fault(SIGFPE, si_code,
> +                       send_sig_fault_trapno(SIGFPE, si_code,
>                                        (void __user *)NULL,  /* FIXME */
>                                        0, current);
>                 }
> diff --git a/arch/alpha/kernel/signal.c b/arch/alpha/kernel/signal.c
> index 948b89789da8..bc077babafab 100644
> --- a/arch/alpha/kernel/signal.c
> +++ b/arch/alpha/kernel/signal.c
> @@ -219,7 +219,7 @@ do_sigreturn(struct sigcontext __user *sc)
>
>         /* Send SIGTRAP if we're single-stepping: */
>         if (ptrace_cancel_bpt (current)) {
> -               send_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *) regs->pc, 0,
> +               send_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *) regs->pc,
>                                current);
>         }
>         return;
> @@ -247,7 +247,7 @@ do_rt_sigreturn(struct rt_sigframe __user *frame)
>
>         /* Send SIGTRAP if we're single-stepping: */
>         if (ptrace_cancel_bpt (current)) {
> -               send_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *) regs->pc, 0,
> +               send_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *) regs->pc,
>                                current);
>         }
>         return;
> diff --git a/arch/alpha/kernel/traps.c b/arch/alpha/kernel/traps.c
> index 921d4b6e4d95..e9e3de18793b 100644
> --- a/arch/alpha/kernel/traps.c
> +++ b/arch/alpha/kernel/traps.c
> @@ -227,7 +227,7 @@ do_entArith(unsigned long summary, unsigned long write_mask,
>         }
>         die_if_kernel("Arithmetic fault", regs, 0, NULL);
>
> -       send_sig_fault(SIGFPE, si_code, (void __user *) regs->pc, 0, current);
> +       send_sig_fault_trapno(SIGFPE, si_code, (void __user *) regs->pc, 0, current);
>  }
>
>  asmlinkage void
> @@ -268,13 +268,13 @@ do_entIF(unsigned long type, struct pt_regs *regs)
>                         regs->pc -= 4;  /* make pc point to former bpt */
>                 }
>
> -               send_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc, 0,
> +               send_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc,
>                                current);
>                 return;
>
>               case 1: /* bugcheck */
> -               send_sig_fault(SIGTRAP, TRAP_UNK, (void __user *) regs->pc, 0,
> -                              current);
> +               send_sig_fault_trapno(SIGTRAP, TRAP_UNK,
> +                                     (void __user *) regs->pc, 0, current);
>                 return;
>
>               case 2: /* gentrap */
> @@ -335,8 +335,8 @@ do_entIF(unsigned long type, struct pt_regs *regs)
>                         break;
>                 }
>
> -               send_sig_fault(signo, code, (void __user *) regs->pc, regs->r16,
> -                              current);
> +               send_sig_fault_trapno(signo, code, (void __user *) regs->pc,
> +                                     regs->r16, current);
>                 return;
>
>               case 4: /* opDEC */
> @@ -360,9 +360,9 @@ do_entIF(unsigned long type, struct pt_regs *regs)
>                         if (si_code == 0)
>                                 return;
>                         if (si_code > 0) {
> -                               send_sig_fault(SIGFPE, si_code,
> -                                              (void __user *) regs->pc, 0,
> -                                              current);
> +                               send_sig_fault_trapno(SIGFPE, si_code,
> +                                                     (void __user *) regs->pc,
> +                                                     0, current);
>                                 return;
>                         }
>                 }
> @@ -387,7 +387,7 @@ do_entIF(unsigned long type, struct pt_regs *regs)
>                       ;
>         }
>
> -       send_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)regs->pc, 0, current);
> +       send_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)regs->pc, current);
>  }
>
>  /* There is an ifdef in the PALcode in MILO that enables a
> @@ -402,7 +402,7 @@ do_entDbg(struct pt_regs *regs)
>  {
>         die_if_kernel("Instruction fault", regs, 0, NULL);
>
> -       force_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)regs->pc, 0);
> +       force_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)regs->pc);
>  }
>
>
> @@ -964,12 +964,12 @@ do_entUnaUser(void __user * va, unsigned long opcode,
>                         si_code = SEGV_MAPERR;
>                 mmap_read_unlock(mm);
>         }
> -       send_sig_fault(SIGSEGV, si_code, va, 0, current);
> +       send_sig_fault(SIGSEGV, si_code, va, current);
>         return;
>
>  give_sigbus:
>         regs->pc -= 4;
> -       send_sig_fault(SIGBUS, BUS_ADRALN, va, 0, current);
> +       send_sig_fault(SIGBUS, BUS_ADRALN, va, current);
>         return;
>  }
>
> diff --git a/arch/alpha/mm/fault.c b/arch/alpha/mm/fault.c
> index 09172f017efc..eee5102c3d88 100644
> --- a/arch/alpha/mm/fault.c
> +++ b/arch/alpha/mm/fault.c
> @@ -219,13 +219,13 @@ do_page_fault(unsigned long address, unsigned long mmcsr,
>         mmap_read_unlock(mm);
>         /* Send a sigbus, regardless of whether we were in kernel
>            or user mode.  */
> -       force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *) address, 0);
> +       force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *) address);
>         if (!user_mode(regs))
>                 goto no_context;
>         return;
>
>   do_sigsegv:
> -       force_sig_fault(SIGSEGV, si_code, (void __user *) address, 0);
> +       force_sig_fault(SIGSEGV, si_code, (void __user *) address);
>         return;
>
>  #ifdef CONFIG_ALPHA_LARGE_VMALLOC
> diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h
> index 99a9ab2b169a..6657184cef07 100644
> --- a/include/linux/sched/signal.h
> +++ b/include/linux/sched/signal.h
> @@ -330,6 +330,8 @@ int force_sig_perf(void __user *addr, u32 type, u64 sig_data);
>
>  int force_sig_ptrace_errno_trap(int errno, void __user *addr);
>  int force_sig_fault_trapno(int sig, int code, void __user *addr, int trapno);
> +int send_sig_fault_trapno(int sig, int code, void __user *addr, int trapno,
> +                       struct task_struct *t);
>
>  extern int send_sig_info(int, struct kernel_siginfo *, struct task_struct *);
>  extern void force_sigsegv(int sig);
> diff --git a/kernel/signal.c b/kernel/signal.c
> index 87a374225277..ae06a424aa72 100644
> --- a/kernel/signal.c
> +++ b/kernel/signal.c
> @@ -1824,6 +1824,23 @@ int force_sig_fault_trapno(int sig, int code, void __user *addr, int trapno)
>         return force_sig_info(&info);
>  }
>
> +/* For the rare architectures that include trap information using
> + * si_trapno.
> + */
> +int send_sig_fault_trapno(int sig, int code, void __user *addr, int trapno,
> +                         struct task_struct *t)
> +{
> +       struct kernel_siginfo info;
> +
> +       clear_siginfo(&info);
> +       info.si_signo = sig;
> +       info.si_errno = 0;
> +       info.si_code  = code;
> +       info.si_addr  = addr;
> +       info.si_trapno = trapno;
> +       return send_sig_info(info.si_signo, &info, t);
> +}
> +
>  int kill_pgrp(struct pid *pid, int sig, int priv)
>  {
>         int ret;
> @@ -3262,6 +3279,10 @@ enum siginfo_layout siginfo_layout(unsigned sig, int si_code)
>                         else if (IS_ENABLED(CONFIG_SPARC) &&
>                                  (sig == SIGILL) && (si_code == ILL_ILLTRP))
>                                 layout = SIL_FAULT_TRAPNO;
> +                       else if (IS_ENABLED(CONFIG_ALPHA) &&
> +                                ((sig == SIGFPE) ||
> +                                 ((sig == SIGTRAP) && (si_code == TRAP_UNK))))
> +                               layout = SIL_FAULT_TRAPNO;
>  #ifdef __ARCH_SI_TRAPNO
>                         else if (layout == SIL_FAULT)
>                                 layout = SIL_FAULT_TRAPNO;
> --
> 2.20.1
>
diff mbox series

Patch

diff --git a/arch/alpha/include/uapi/asm/siginfo.h b/arch/alpha/include/uapi/asm/siginfo.h
index 6e1a2af2f962..e08eae88182b 100644
--- a/arch/alpha/include/uapi/asm/siginfo.h
+++ b/arch/alpha/include/uapi/asm/siginfo.h
@@ -2,8 +2,6 @@ 
 #ifndef _ALPHA_SIGINFO_H
 #define _ALPHA_SIGINFO_H
 
-#define __ARCH_SI_TRAPNO
-
 #include <asm-generic/siginfo.h>
 
 #endif
diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c
index d5367a1c6300..bbdb1a9a5fd8 100644
--- a/arch/alpha/kernel/osf_sys.c
+++ b/arch/alpha/kernel/osf_sys.c
@@ -876,7 +876,7 @@  SYSCALL_DEFINE5(osf_setsysinfo, unsigned long, op, void __user *, buffer,
 			if (fex & IEEE_TRAP_ENABLE_DZE) si_code = FPE_FLTDIV;
 			if (fex & IEEE_TRAP_ENABLE_INV) si_code = FPE_FLTINV;
 
-			send_sig_fault(SIGFPE, si_code,
+			send_sig_fault_trapno(SIGFPE, si_code,
 				       (void __user *)NULL,  /* FIXME */
 				       0, current);
  		}
diff --git a/arch/alpha/kernel/signal.c b/arch/alpha/kernel/signal.c
index 948b89789da8..bc077babafab 100644
--- a/arch/alpha/kernel/signal.c
+++ b/arch/alpha/kernel/signal.c
@@ -219,7 +219,7 @@  do_sigreturn(struct sigcontext __user *sc)
 
 	/* Send SIGTRAP if we're single-stepping: */
 	if (ptrace_cancel_bpt (current)) {
-		send_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *) regs->pc, 0,
+		send_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *) regs->pc,
 			       current);
 	}
 	return;
@@ -247,7 +247,7 @@  do_rt_sigreturn(struct rt_sigframe __user *frame)
 
 	/* Send SIGTRAP if we're single-stepping: */
 	if (ptrace_cancel_bpt (current)) {
-		send_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *) regs->pc, 0,
+		send_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *) regs->pc,
 			       current);
 	}
 	return;
diff --git a/arch/alpha/kernel/traps.c b/arch/alpha/kernel/traps.c
index 921d4b6e4d95..e9e3de18793b 100644
--- a/arch/alpha/kernel/traps.c
+++ b/arch/alpha/kernel/traps.c
@@ -227,7 +227,7 @@  do_entArith(unsigned long summary, unsigned long write_mask,
 	}
 	die_if_kernel("Arithmetic fault", regs, 0, NULL);
 
-	send_sig_fault(SIGFPE, si_code, (void __user *) regs->pc, 0, current);
+	send_sig_fault_trapno(SIGFPE, si_code, (void __user *) regs->pc, 0, current);
 }
 
 asmlinkage void
@@ -268,13 +268,13 @@  do_entIF(unsigned long type, struct pt_regs *regs)
 			regs->pc -= 4;	/* make pc point to former bpt */
 		}
 
-		send_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc, 0,
+		send_sig_fault(SIGTRAP, TRAP_BRKPT, (void __user *)regs->pc,
 			       current);
 		return;
 
 	      case 1: /* bugcheck */
-		send_sig_fault(SIGTRAP, TRAP_UNK, (void __user *) regs->pc, 0,
-			       current);
+		send_sig_fault_trapno(SIGTRAP, TRAP_UNK,
+				      (void __user *) regs->pc, 0, current);
 		return;
 		
 	      case 2: /* gentrap */
@@ -335,8 +335,8 @@  do_entIF(unsigned long type, struct pt_regs *regs)
 			break;
 		}
 
-		send_sig_fault(signo, code, (void __user *) regs->pc, regs->r16,
-			       current);
+		send_sig_fault_trapno(signo, code, (void __user *) regs->pc,
+				      regs->r16, current);
 		return;
 
 	      case 4: /* opDEC */
@@ -360,9 +360,9 @@  do_entIF(unsigned long type, struct pt_regs *regs)
 			if (si_code == 0)
 				return;
 			if (si_code > 0) {
-				send_sig_fault(SIGFPE, si_code,
-					       (void __user *) regs->pc, 0,
-					       current);
+				send_sig_fault_trapno(SIGFPE, si_code,
+						      (void __user *) regs->pc,
+						      0, current);
 				return;
 			}
 		}
@@ -387,7 +387,7 @@  do_entIF(unsigned long type, struct pt_regs *regs)
 		      ;
 	}
 
-	send_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)regs->pc, 0, current);
+	send_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)regs->pc, current);
 }
 
 /* There is an ifdef in the PALcode in MILO that enables a 
@@ -402,7 +402,7 @@  do_entDbg(struct pt_regs *regs)
 {
 	die_if_kernel("Instruction fault", regs, 0, NULL);
 
-	force_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)regs->pc, 0);
+	force_sig_fault(SIGILL, ILL_ILLOPC, (void __user *)regs->pc);
 }
 
 
@@ -964,12 +964,12 @@  do_entUnaUser(void __user * va, unsigned long opcode,
 			si_code = SEGV_MAPERR;
 		mmap_read_unlock(mm);
 	}
-	send_sig_fault(SIGSEGV, si_code, va, 0, current);
+	send_sig_fault(SIGSEGV, si_code, va, current);
 	return;
 
 give_sigbus:
 	regs->pc -= 4;
-	send_sig_fault(SIGBUS, BUS_ADRALN, va, 0, current);
+	send_sig_fault(SIGBUS, BUS_ADRALN, va, current);
 	return;
 }
 
diff --git a/arch/alpha/mm/fault.c b/arch/alpha/mm/fault.c
index 09172f017efc..eee5102c3d88 100644
--- a/arch/alpha/mm/fault.c
+++ b/arch/alpha/mm/fault.c
@@ -219,13 +219,13 @@  do_page_fault(unsigned long address, unsigned long mmcsr,
 	mmap_read_unlock(mm);
 	/* Send a sigbus, regardless of whether we were in kernel
 	   or user mode.  */
-	force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *) address, 0);
+	force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *) address);
 	if (!user_mode(regs))
 		goto no_context;
 	return;
 
  do_sigsegv:
-	force_sig_fault(SIGSEGV, si_code, (void __user *) address, 0);
+	force_sig_fault(SIGSEGV, si_code, (void __user *) address);
 	return;
 
 #ifdef CONFIG_ALPHA_LARGE_VMALLOC
diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h
index 99a9ab2b169a..6657184cef07 100644
--- a/include/linux/sched/signal.h
+++ b/include/linux/sched/signal.h
@@ -330,6 +330,8 @@  int force_sig_perf(void __user *addr, u32 type, u64 sig_data);
 
 int force_sig_ptrace_errno_trap(int errno, void __user *addr);
 int force_sig_fault_trapno(int sig, int code, void __user *addr, int trapno);
+int send_sig_fault_trapno(int sig, int code, void __user *addr, int trapno,
+			struct task_struct *t);
 
 extern int send_sig_info(int, struct kernel_siginfo *, struct task_struct *);
 extern void force_sigsegv(int sig);
diff --git a/kernel/signal.c b/kernel/signal.c
index 87a374225277..ae06a424aa72 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1824,6 +1824,23 @@  int force_sig_fault_trapno(int sig, int code, void __user *addr, int trapno)
 	return force_sig_info(&info);
 }
 
+/* For the rare architectures that include trap information using
+ * si_trapno.
+ */
+int send_sig_fault_trapno(int sig, int code, void __user *addr, int trapno,
+			  struct task_struct *t)
+{
+	struct kernel_siginfo info;
+
+	clear_siginfo(&info);
+	info.si_signo = sig;
+	info.si_errno = 0;
+	info.si_code  = code;
+	info.si_addr  = addr;
+	info.si_trapno = trapno;
+	return send_sig_info(info.si_signo, &info, t);
+}
+
 int kill_pgrp(struct pid *pid, int sig, int priv)
 {
 	int ret;
@@ -3262,6 +3279,10 @@  enum siginfo_layout siginfo_layout(unsigned sig, int si_code)
 			else if (IS_ENABLED(CONFIG_SPARC) &&
 				 (sig == SIGILL) && (si_code == ILL_ILLTRP))
 				layout = SIL_FAULT_TRAPNO;
+			else if (IS_ENABLED(CONFIG_ALPHA) &&
+				 ((sig == SIGFPE) ||
+				  ((sig == SIGTRAP) && (si_code == TRAP_UNK))))
+				layout = SIL_FAULT_TRAPNO;
 #ifdef __ARCH_SI_TRAPNO
 			else if (layout == SIL_FAULT)
 				layout = SIL_FAULT_TRAPNO;