[REVIEW][PATCH 00/17] siginfo bugfixes and cleanups

[REVIEW][PATCH 00/17] siginfo bugfixes and cleanups

[Eric W. Biederman]

Mostly this dealing with aliases of SI_USER, that make it impossible for
userspace to tell what kind of siginfo it has received.

Also in this series is the change to ensure we have siginfo initialized
so I can rip out the switch in copy_siginfo_to_user for better
performance, and to ensure better backwards compatibility as siginfo as
generated in the callers is passed to userspace.

There are also fixes for a few other siginfo bugs I have found.

There are cleanups of ifdefs on SEGV_BNDERR and BUS_MCERR_AX that are no
longer necessary.

I plan to merge these bug fixes through my siginfo tree, but if you
object to them or would prefer to have them go through your arch tree
please let me know.

The changes are avaiable as a totality at:
    git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git siginfo-review
    
Dmitry V. Levin (1):
      sparc: fix compat siginfo ABI regression

Eric W. Biederman (16):
      signal/alpha: Document a conflict with SI_USER for SIGFPE
      signal/sh: Use force_sig_fault in hw_breakpoint_handler
      signal/nds32: Use force_sig in unhandled_interruption and unhandled_exceptions
      signal/nds32: Use force_sig(SIGILL) in do_revisn
      signal: Ensure every siginfo we send has all bits initialized
      signal: Reduce copy_siginfo_to_user to just copy_to_user
      signal: Stop special casing TRAP_FIXME and FPE_FIXME in siginfo_layout
      signal: Remove SEGV_BNDERR ifdefs
      signal: Remove ifdefs for BUS_MCEERR_AR and BUS_MCEERR_AO
      signal/alpha: Replace FPE_FIXME with FPE_FLTUNK
      signal/ia64: Replace FPE_FIXME with FPE_FLTUNK
      signal/powerpc: Replace FPE_FIXME with FPE_FLTUNK
      signal/unicore32: Use FPE_FLTUNK instead of 0 in ucf64_raise_sigfpe
      signal: Add TRAP_UNK si_code for undiagnosted trap exceptions
      signal/alpha:  Replace TRAP_FIXME with TRAP_UNK
      signal/powerpc: Replace TRAP_FIXME with TRAP_UNK

 arch/alpha/include/uapi/asm/siginfo.h     |  14 ----
 arch/alpha/kernel/osf_sys.c               |   3 +-
 arch/alpha/kernel/signal.c                |   2 +
 arch/alpha/kernel/traps.c                 |  11 ++-
 arch/alpha/mm/fault.c                     |   2 +
 arch/arc/mm/fault.c                       |   2 +
 arch/arm/kernel/ptrace.c                  |   1 +
 arch/arm/kernel/swp_emulate.c             |   1 +
 arch/arm/kernel/traps.c                   |   5 ++
 arch/arm/mm/alignment.c                   |   1 +
 arch/arm/mm/fault.c                       |   4 +
 arch/arm/vfp/vfpmodule.c                  |   3 +-
 arch/arm64/kernel/fpsimd.c                |   2 +-
 arch/arm64/kernel/sys_compat.c            |   1 +
 arch/arm64/kernel/traps.c                 |   1 +
 arch/arm64/mm/fault.c                     |  18 +++--
 arch/c6x/kernel/traps.c                   |   1 +
 arch/hexagon/kernel/traps.c               |   1 +
 arch/hexagon/mm/vm_fault.c                |   1 +
 arch/ia64/include/uapi/asm/siginfo.h      |   7 --
 arch/ia64/kernel/brl_emu.c                |   1 +
 arch/ia64/kernel/signal.c                 |   2 +
 arch/ia64/kernel/traps.c                  |  31 ++++++--
 arch/ia64/kernel/unaligned.c              |   1 +
 arch/ia64/mm/fault.c                      |   4 +-
 arch/m68k/kernel/traps.c                  |   2 +
 arch/microblaze/kernel/exceptions.c       |   1 +
 arch/microblaze/mm/fault.c                |   4 +-
 arch/mips/mm/fault.c                      |   1 +
 arch/nds32/kernel/traps.c                 |  19 ++---
 arch/nds32/mm/fault.c                     |   1 +
 arch/nios2/kernel/traps.c                 |   1 +
 arch/openrisc/kernel/traps.c              |   5 +-
 arch/openrisc/mm/fault.c                  |   1 +
 arch/parisc/kernel/ptrace.c               |   1 +
 arch/parisc/kernel/traps.c                |   2 +
 arch/parisc/kernel/unaligned.c            |   1 +
 arch/parisc/math-emu/driver.c             |   1 +
 arch/parisc/mm/fault.c                    |   1 +
 arch/powerpc/include/uapi/asm/siginfo.h   |  15 ----
 arch/powerpc/kernel/process.c             |   1 +
 arch/powerpc/kernel/traps.c               |  13 ++--
 arch/powerpc/mm/fault.c                   |   1 +
 arch/powerpc/platforms/cell/spufs/fault.c |   2 +-
 arch/riscv/kernel/traps.c                 |   1 +
 arch/s390/kernel/traps.c                  |   5 +-
 arch/s390/mm/fault.c                      |   2 +
 arch/sh/kernel/hw_breakpoint.c            |   9 +--
 arch/sh/kernel/traps_32.c                 |   2 +
 arch/sh/math-emu/math.c                   |   1 +
 arch/sh/mm/fault.c                        |   1 +
 arch/sparc/include/uapi/asm/siginfo.h     |   7 --
 arch/sparc/kernel/process_64.c            |   1 +
 arch/sparc/kernel/sys_sparc_32.c          |   1 +
 arch/sparc/kernel/traps_32.c              |  12 ++-
 arch/sparc/kernel/traps_64.c              |  16 +++-
 arch/sparc/kernel/unaligned_32.c          |   1 +
 arch/sparc/mm/fault_32.c                  |   1 +
 arch/sparc/mm/fault_64.c                  |   1 +
 arch/um/kernel/trap.c                     |   2 +
 arch/unicore32/kernel/fpu-ucf64.c         |   8 +-
 arch/unicore32/mm/fault.c                 |   3 +
 arch/x86/entry/vsyscall/vsyscall_64.c     |   2 +-
 arch/x86/kernel/ptrace.c                  |   2 +-
 arch/x86/kernel/signal_compat.c           |   2 +-
 arch/x86/kernel/traps.c                   |   3 +
 arch/x86/kernel/umip.c                    |   1 +
 arch/x86/kvm/mmu.c                        |   1 +
 arch/x86/mm/fault.c                       |   1 +
 arch/xtensa/kernel/traps.c                |   1 +
 arch/xtensa/mm/fault.c                    |   1 +
 fs/signalfd.c                             |  15 +---
 include/linux/ptrace.h                    |   1 -
 include/linux/tracehook.h                 |   1 +
 include/uapi/asm-generic/siginfo.h        |   3 +-
 kernel/signal.c                           | 123 +++---------------------------
 virt/kvm/arm/mmu.c                        |   1 +
 77 files changed, 194 insertions(+), 231 deletions(-)

[REVIEW][PATCH 01/17] signal/alpha: Document a conflict with SI_USER for SIGFPE

[Eric W. Biederman]

Setting si_code to 0 is the same as setting si_code to SI_USER.  This
is the same si_code as SI_USER.  Posix and common sense requires that
SI_USER not be a signal specific si_code.  As such this use of 0 for
the si_code is a pretty horribly broken ABI.

Cc: Helge Deller <deller@gmx.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: linux-alpha@vger.kernel.org
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Ref: 0a635c7a84cf ("Fill in siginfo_t.")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/alpha/kernel/osf_sys.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c
index 89faa6f4de47..2e02aef5a334 100644
--- a/arch/alpha/kernel/osf_sys.c
+++ b/arch/alpha/kernel/osf_sys.c
@@ -872,7 +872,7 @@ SYSCALL_DEFINE5(osf_setsysinfo, unsigned long, op, void __user *, buffer,
 		fex = (exc >> IEEE_STATUS_TO_EXCSUM_SHIFT) & swcr;
  		if (fex) {
 			siginfo_t info;
-			int si_code = 0;
+			int si_code = FPE_FIXME;
 
 			if (fex & IEEE_TRAP_ENABLE_DNO) si_code = FPE_FLTUND;
 			if (fex & IEEE_TRAP_ENABLE_INE) si_code = FPE_FLTRES;
-- 
2.14.1

[REVIEW][PATCH 02/17] sparc: fix compat siginfo ABI regression

[Eric W. Biederman]

From: "Dmitry V. Levin" <ldv@altlinux.org>

Starting with commit v4.14-rc1~60^2^2~1, a SIGFPE signal sent via kill
results to wrong values in si_pid and si_uid fields of compat siginfo_t.

This happens due to FPE_FIXME being defined to 0 for sparc, and at the
same time siginfo_layout() introduced by the same commit returns
SIL_FAULT for SIGFPE if si_code == SI_USER and FPE_FIXME is defined to 0.

Fix this regression by removing FPE_FIXME macro and changing all its users
to assign FPE_FLTUNK to si_code instead of FPE_FIXME.

Note that FPE_FLTUNK is a new macro introduced by commit
266da65e9156d93e1126e185259a4aae68188d0e.

Tested with commit v4.16-11958-g16e205cf42da.

This bug was found by strace test suite.

In the discussion about FPE_FLTUNK on sparc David Miller said:
> Eric, feel free to do something similar on Sparc.

Link: https://github.com/strace/strace/issues/21
Fixes: cc731525f26a ("signal: Remove kernel interal si_code magic")
Fixes: 2.3.41
Cc: David Miller <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Conceptually-Acked-By: David Miller <davem@davemloft.net>
Thanks-to: Anatoly Pugachev <matorola@gmail.com>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
---
 arch/sparc/include/uapi/asm/siginfo.h | 7 -------
 arch/sparc/kernel/traps_32.c          | 2 +-
 arch/sparc/kernel/traps_64.c          | 2 +-
 3 files changed, 2 insertions(+), 9 deletions(-)

diff --git a/arch/sparc/include/uapi/asm/siginfo.h b/arch/sparc/include/uapi/asm/siginfo.h
index 896ce447d16a..e7049550ac82 100644
--- a/arch/sparc/include/uapi/asm/siginfo.h
+++ b/arch/sparc/include/uapi/asm/siginfo.h
@@ -17,13 +17,6 @@
 
 #define SI_NOINFO	32767		/* no information in siginfo_t */
 
-/*
- * SIGFPE si_codes
- */
-#ifdef __KERNEL__
-#define FPE_FIXME	0	/* Broken dup of SI_USER */
-#endif /* __KERNEL__ */
-
 /*
  * SIGEMT si_codes
  */
diff --git a/arch/sparc/kernel/traps_32.c b/arch/sparc/kernel/traps_32.c
index b1ed763e4787..33cd35bf3dc8 100644
--- a/arch/sparc/kernel/traps_32.c
+++ b/arch/sparc/kernel/traps_32.c
@@ -307,7 +307,7 @@ void do_fpe_trap(struct pt_regs *regs, unsigned long pc, unsigned long npc,
 	info.si_errno = 0;
 	info.si_addr = (void __user *)pc;
 	info.si_trapno = 0;
-	info.si_code = FPE_FIXME;
+	info.si_code = FPE_FLTUNK;
 	if ((fsr & 0x1c000) == (1 << 14)) {
 		if (fsr & 0x10)
 			info.si_code = FPE_FLTINV;
diff --git a/arch/sparc/kernel/traps_64.c b/arch/sparc/kernel/traps_64.c
index 462a21abd105..e81072ac52c3 100644
--- a/arch/sparc/kernel/traps_64.c
+++ b/arch/sparc/kernel/traps_64.c
@@ -2372,7 +2372,7 @@ static void do_fpe_common(struct pt_regs *regs)
 		info.si_errno = 0;
 		info.si_addr = (void __user *)regs->tpc;
 		info.si_trapno = 0;
-		info.si_code = FPE_FIXME;
+		info.si_code = FPE_FLTUNK;
 		if ((fsr & 0x1c000) == (1 << 14)) {
 			if (fsr & 0x10)
 				info.si_code = FPE_FLTINV;
-- 
2.14.1

[REVIEW][PATCH 03/17] signal/sh: Use force_sig_fault in hw_breakpoint_handler

[Eric W. Biederman]

The call chain is:
breakpoint
  notify_die
    hw_breakpoint_exceptions_notify
      hw_breakpoint_handler

So the signal number can only be SIGTRAP.

In hw_breakpoint_handler rc is either NOTIFY_STOP or NOTIF_DONE
both of which notifier_to_errno converts to 0.  So si_errno is 0.

Historically si_addr was left unitialized in struct siginfo which is a
bug.  There appears to be no consensus among the various architectures
which value should be in si_addr.  So since no usable value has
been returned up to this point return NULL in si_addr.

Fixes: 4352fc1b12fa ("sh: Abstracted SH-4A UBC support on hw-breakpoint core.")
Fixes: 34d0b5af50a0 ("sh: Convert ptrace to hw_breakpoint API.")
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: linux-sh@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/sh/kernel/hw_breakpoint.c | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/arch/sh/kernel/hw_breakpoint.c b/arch/sh/kernel/hw_breakpoint.c
index afe965712a69..8648ed05ccf0 100644
--- a/arch/sh/kernel/hw_breakpoint.c
+++ b/arch/sh/kernel/hw_breakpoint.c
@@ -347,13 +347,8 @@ static int __kprobes hw_breakpoint_handler(struct die_args *args)
 
 		/* Deliver the signal to userspace */
 		if (!arch_check_bp_in_kernelspace(bp)) {
-			siginfo_t info;
-
-			info.si_signo = args->signr;
-			info.si_errno = notifier_to_errno(rc);
-			info.si_code = TRAP_HWBKPT;
-
-			force_sig_info(args->signr, &info, current);
+			force_sig_fault(SIGTRAP, TRAP_HWBKPT,
+					(void __user *)NULL, current);
 		}
 
 		rcu_read_unlock();
-- 
2.14.1

[REVIEW][PATCH 04/17] signal/nds32: Use force_sig in unhandled_interruption and unhandled_exceptions

[Eric W. Biederman]

Neither unhandled_interrupt nor unhandled_exceptions fills in any of the
siginfo fields whend sending SIGKILL.  Further because it is SIGKILL
even if all of the fields were filled out appropriately it would be impossible
for the process to read any of the siginfo fields.  So simplfy things and
just use force_sig instead of force_sig_info.

Fixes: 2923f5ea7738 ("nds32: Exception handling")
Cc: Vincent Chen <vincentc@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/nds32/kernel/traps.c | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c
index 6e34eb9824a4..65961bf91d64 100644
--- a/arch/nds32/kernel/traps.c
+++ b/arch/nds32/kernel/traps.c
@@ -318,29 +318,22 @@ void do_debug_trap(unsigned long entry, unsigned long addr,
 
 void unhandled_interruption(struct pt_regs *regs)
 {
-	siginfo_t si;
 	pr_emerg("unhandled_interruption\n");
 	show_regs(regs);
 	if (!user_mode(regs))
 		do_exit(SIGKILL);
-	si.si_signo = SIGKILL;
-	si.si_errno = 0;
-	force_sig_info(SIGKILL, &si, current);
+	force_sig(SIGKILL, current);
 }
 
 void unhandled_exceptions(unsigned long entry, unsigned long addr,
 			  unsigned long type, struct pt_regs *regs)
 {
-	siginfo_t si;
 	pr_emerg("Unhandled Exception: entry: %lx addr:%lx itype:%lx\n", entry,
 		 addr, type);
 	show_regs(regs);
 	if (!user_mode(regs))
 		do_exit(SIGKILL);
-	si.si_signo = SIGKILL;
-	si.si_errno = 0;
-	si.si_addr = (void *)addr;
-	force_sig_info(SIGKILL, &si, current);
+	force_sig(SIGKILL, current);
 }
 
 extern int do_page_fault(unsigned long entry, unsigned long addr,
-- 
2.14.1

[REVIEW][PATCH 05/17] signal/nds32: Use force_sig(SIGILL) in do_revisn

[Eric W. Biederman]

As originally committed do_revisn would deliver a siginfo for SIGILL
with an si_code composed of random stack contents.  That makes no
sense and is not something userspace can depend on.  So simplify
the code and just use "force_sig(SIG_ILL, current)" instead.

Fixes: 2923f5ea7738 ("nds32: Exception handling")
Cc: Vincent Chen <vincentc@andestech.com>
Cc: Greentime Hu <greentime@andestech.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/nds32/kernel/traps.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c
index 65961bf91d64..8e9a5b1f6234 100644
--- a/arch/nds32/kernel/traps.c
+++ b/arch/nds32/kernel/traps.c
@@ -356,14 +356,11 @@ void do_dispatch_tlb_misc(unsigned long entry, unsigned long addr,
 
 void do_revinsn(struct pt_regs *regs)
 {
-	siginfo_t si;
 	pr_emerg("Reserved Instruction\n");
 	show_regs(regs);
 	if (!user_mode(regs))
 		do_exit(SIGILL);
-	si.si_signo = SIGILL;
-	si.si_errno = 0;
-	force_sig_info(SIGILL, &si, current);
+	force_sig(SIGILL, current);
 }
 
 #ifdef CONFIG_ALIGNMENT_TRAP
-- 
2.14.1

[REVIEW][PATCH 06/17] signal: Ensure every siginfo we send has all bits initialized

[Eric W. Biederman]

Call clear_siginfo to ensure every stack allocated siginfo is properly
initialized before being passed to the signal sending functions.

Note: It is not safe to depend on C initializers to initialize struct
siginfo on the stack because C is allowed to skip holes when
initializing a structure.

The initialization of struct siginfo in tracehook_report_syscall_exit
was moved from the helper user_single_step_siginfo into
tracehook_report_syscall_exit itself, to make it clear that the local
variable siginfo gets fully initialized.

In a few cases the scope of struct siginfo has been reduced to make it
clear that siginfo siginfo is not used on other paths in the function
in which it is declared.

Instances of using memset to initialize siginfo have been replaced
with calls clear_siginfo for clarity.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/alpha/kernel/osf_sys.c               |  1 +
 arch/alpha/kernel/signal.c                |  2 ++
 arch/alpha/kernel/traps.c                 |  5 +++++
 arch/alpha/mm/fault.c                     |  2 ++
 arch/arc/mm/fault.c                       |  2 ++
 arch/arm/kernel/ptrace.c                  |  1 +
 arch/arm/kernel/swp_emulate.c             |  1 +
 arch/arm/kernel/traps.c                   |  5 +++++
 arch/arm/mm/alignment.c                   |  1 +
 arch/arm/mm/fault.c                       |  4 ++++
 arch/arm/vfp/vfpmodule.c                  |  3 +--
 arch/arm64/kernel/fpsimd.c                |  2 +-
 arch/arm64/kernel/sys_compat.c            |  1 +
 arch/arm64/kernel/traps.c                 |  1 +
 arch/arm64/mm/fault.c                     | 18 ++++++++++++------
 arch/c6x/kernel/traps.c                   |  1 +
 arch/hexagon/kernel/traps.c               |  1 +
 arch/hexagon/mm/vm_fault.c                |  1 +
 arch/ia64/kernel/brl_emu.c                |  1 +
 arch/ia64/kernel/signal.c                 |  2 ++
 arch/ia64/kernel/traps.c                  | 27 ++++++++++++++++++++++++---
 arch/ia64/kernel/unaligned.c              |  1 +
 arch/ia64/mm/fault.c                      |  4 +++-
 arch/m68k/kernel/traps.c                  |  2 ++
 arch/microblaze/kernel/exceptions.c       |  1 +
 arch/microblaze/mm/fault.c                |  4 +++-
 arch/mips/mm/fault.c                      |  1 +
 arch/nds32/kernel/traps.c                 |  3 ++-
 arch/nds32/mm/fault.c                     |  1 +
 arch/nios2/kernel/traps.c                 |  1 +
 arch/openrisc/kernel/traps.c              |  5 ++++-
 arch/openrisc/mm/fault.c                  |  1 +
 arch/parisc/kernel/ptrace.c               |  1 +
 arch/parisc/kernel/traps.c                |  2 ++
 arch/parisc/kernel/unaligned.c            |  1 +
 arch/parisc/math-emu/driver.c             |  1 +
 arch/parisc/mm/fault.c                    |  1 +
 arch/powerpc/kernel/process.c             |  1 +
 arch/powerpc/kernel/traps.c               |  3 +--
 arch/powerpc/mm/fault.c                   |  1 +
 arch/powerpc/platforms/cell/spufs/fault.c |  2 +-
 arch/riscv/kernel/traps.c                 |  1 +
 arch/s390/kernel/traps.c                  |  5 ++++-
 arch/s390/mm/fault.c                      |  2 ++
 arch/sh/kernel/traps_32.c                 |  2 ++
 arch/sh/math-emu/math.c                   |  1 +
 arch/sh/mm/fault.c                        |  1 +
 arch/sparc/kernel/process_64.c            |  1 +
 arch/sparc/kernel/sys_sparc_32.c          |  1 +
 arch/sparc/kernel/traps_32.c              | 10 ++++++++++
 arch/sparc/kernel/traps_64.c              | 14 ++++++++++++++
 arch/sparc/kernel/unaligned_32.c          |  1 +
 arch/sparc/mm/fault_32.c                  |  1 +
 arch/sparc/mm/fault_64.c                  |  1 +
 arch/um/kernel/trap.c                     |  2 ++
 arch/unicore32/kernel/fpu-ucf64.c         |  2 +-
 arch/unicore32/mm/fault.c                 |  3 +++
 arch/x86/entry/vsyscall/vsyscall_64.c     |  2 +-
 arch/x86/kernel/ptrace.c                  |  2 +-
 arch/x86/kernel/traps.c                   |  3 +++
 arch/x86/kernel/umip.c                    |  1 +
 arch/x86/kvm/mmu.c                        |  1 +
 arch/x86/mm/fault.c                       |  1 +
 arch/xtensa/kernel/traps.c                |  1 +
 arch/xtensa/mm/fault.c                    |  1 +
 include/linux/ptrace.h                    |  1 -
 include/linux/tracehook.h                 |  1 +
 virt/kvm/arm/mmu.c                        |  1 +
 68 files changed, 158 insertions(+), 24 deletions(-)

diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c
index 2e02aef5a334..f5f154942aab 100644
--- a/arch/alpha/kernel/osf_sys.c
+++ b/arch/alpha/kernel/osf_sys.c
@@ -881,6 +881,7 @@ 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;
 
+			clear_siginfo(&info);
 			info.si_signo = SIGFPE;
 			info.si_errno = 0;
 			info.si_code = si_code;
diff --git a/arch/alpha/kernel/signal.c b/arch/alpha/kernel/signal.c
index 9ebb3bcbc626..cd306e602313 100644
--- a/arch/alpha/kernel/signal.c
+++ b/arch/alpha/kernel/signal.c
@@ -221,6 +221,7 @@ do_sigreturn(struct sigcontext __user *sc)
 	if (ptrace_cancel_bpt (current)) {
 		siginfo_t info;
 
+		clear_siginfo(&info);
 		info.si_signo = SIGTRAP;
 		info.si_errno = 0;
 		info.si_code = TRAP_BRKPT;
@@ -255,6 +256,7 @@ do_rt_sigreturn(struct rt_sigframe __user *frame)
 	if (ptrace_cancel_bpt (current)) {
 		siginfo_t info;
 
+		clear_siginfo(&info);
 		info.si_signo = SIGTRAP;
 		info.si_errno = 0;
 		info.si_code = TRAP_BRKPT;
diff --git a/arch/alpha/kernel/traps.c b/arch/alpha/kernel/traps.c
index f43bd05dede2..91636765dd6d 100644
--- a/arch/alpha/kernel/traps.c
+++ b/arch/alpha/kernel/traps.c
@@ -228,6 +228,7 @@ do_entArith(unsigned long summary, unsigned long write_mask,
 	}
 	die_if_kernel("Arithmetic fault", regs, 0, NULL);
 
+	clear_siginfo(&info);
 	info.si_signo = SIGFPE;
 	info.si_errno = 0;
 	info.si_code = si_code;
@@ -241,6 +242,7 @@ do_entIF(unsigned long type, struct pt_regs *regs)
 	siginfo_t info;
 	int signo, code;
 
+	clear_siginfo(&info);
 	if ((regs->ps & ~IPL_MAX) == 0) {
 		if (type == 1) {
 			const unsigned int *data
@@ -430,6 +432,7 @@ do_entDbg(struct pt_regs *regs)
 
 	die_if_kernel("Instruction fault", regs, 0, NULL);
 
+	clear_siginfo(&info);
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code = ILL_ILLOPC;
@@ -761,6 +764,8 @@ do_entUnaUser(void __user * va, unsigned long opcode,
 	siginfo_t info;
 	long error;
 
+	clear_siginfo(&info);
+
 	/* Check the UAC bits to decide what the user wants us to do
 	   with the unaliged access.  */
 
diff --git a/arch/alpha/mm/fault.c b/arch/alpha/mm/fault.c
index cd3c572ee912..7f2202a9f50a 100644
--- a/arch/alpha/mm/fault.c
+++ b/arch/alpha/mm/fault.c
@@ -91,6 +91,8 @@ do_page_fault(unsigned long address, unsigned long mmcsr,
 	siginfo_t info;
 	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
 
+	clear_siginfo(&info);
+
 	/* As of EV6, a load into $31/$f31 is a prefetch, and never faults
 	   (or is suppressed by the PALcode).  Support that for older CPUs
 	   by ignoring such an instruction.  */
diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c
index a0b7bd6d030d..b884bbd6f354 100644
--- a/arch/arc/mm/fault.c
+++ b/arch/arc/mm/fault.c
@@ -70,6 +70,8 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
 	int write = regs->ecr_cause & ECR_C_PROTV_STORE;  /* ST/EX */
 	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
 
+	clear_siginfo(&info);
+
 	/*
 	 * We fault-in kernel-space virtual memory on-demand. The
 	 * 'reference' page table is init_mm.pgd.
diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index 7724b0f661b3..36718a424358 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -205,6 +205,7 @@ void ptrace_break(struct task_struct *tsk, struct pt_regs *regs)
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_signo = SIGTRAP;
 	info.si_errno = 0;
 	info.si_code  = TRAP_BRKPT;
diff --git a/arch/arm/kernel/swp_emulate.c b/arch/arm/kernel/swp_emulate.c
index 3bda08bee674..dfcb456afadd 100644
--- a/arch/arm/kernel/swp_emulate.c
+++ b/arch/arm/kernel/swp_emulate.c
@@ -112,6 +112,7 @@ static void set_segfault(struct pt_regs *regs, unsigned long addr)
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	down_read(&current->mm->mmap_sem);
 	if (find_vma(current->mm, addr) == NULL)
 		info.si_code = SEGV_MAPERR;
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index 5e3633c24e63..2584f9066da3 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -439,6 +439,7 @@ asmlinkage void do_undefinstr(struct pt_regs *regs)
 	siginfo_t info;
 	void __user *pc;
 
+	clear_siginfo(&info);
 	pc = (void __user *)instruction_pointer(regs);
 
 	if (processor_mode(regs) == SVC_MODE) {
@@ -537,6 +538,7 @@ static int bad_syscall(int n, struct pt_regs *regs)
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	if ((current->personality & PER_MASK) != PER_LINUX) {
 		send_sig(SIGSEGV, current, 1);
 		return regs->ARM_r0;
@@ -604,6 +606,7 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs)
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	if ((no >> 16) != (__ARM_NR_BASE>> 16))
 		return bad_syscall(no, regs);
 
@@ -740,6 +743,8 @@ baddataabort(int code, unsigned long instr, struct pt_regs *regs)
 	unsigned long addr = instruction_pointer(regs);
 	siginfo_t info;
 
+	clear_siginfo(&info);
+
 #ifdef CONFIG_DEBUG_USER
 	if (user_debug & UDBG_BADABORT) {
 		pr_err("[%d] %s: bad data abort: code %d instr 0x%08lx\n",
diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c
index 2c96190e018b..bd2c739d8083 100644
--- a/arch/arm/mm/alignment.c
+++ b/arch/arm/mm/alignment.c
@@ -950,6 +950,7 @@ do_alignment(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 	if (ai_usermode & UM_SIGNAL) {
 		siginfo_t si;
 
+		clear_siginfo(&si);
 		si.si_signo = SIGBUS;
 		si.si_errno = 0;
 		si.si_code = BUS_ADRALN;
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index b75eada23d0a..32034543f49c 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -163,6 +163,8 @@ __do_user_fault(struct task_struct *tsk, unsigned long addr,
 {
 	struct siginfo si;
 
+	clear_siginfo(&si);
+
 #ifdef CONFIG_DEBUG_USER
 	if (((user_debug & UDBG_SEGV) && (sig == SIGSEGV)) ||
 	    ((user_debug & UDBG_BUS)  && (sig == SIGBUS))) {
@@ -557,6 +559,7 @@ do_DataAbort(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 		inf->name, fsr, addr);
 	show_pte(current->mm, addr);
 
+	clear_siginfo(&info);
 	info.si_signo = inf->sig;
 	info.si_errno = 0;
 	info.si_code  = inf->code;
@@ -589,6 +592,7 @@ do_PrefetchAbort(unsigned long addr, unsigned int ifsr, struct pt_regs *regs)
 	pr_alert("Unhandled prefetch abort: %s (0x%03x) at 0x%08lx\n",
 		inf->name, ifsr, addr);
 
+	clear_siginfo(&info);
 	info.si_signo = inf->sig;
 	info.si_errno = 0;
 	info.si_code  = inf->code;
diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index 4c375e11ae95..adda3fc2dde8 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -218,8 +218,7 @@ static void vfp_raise_sigfpe(unsigned int sicode, struct pt_regs *regs)
 {
 	siginfo_t info;
 
-	memset(&info, 0, sizeof(info));
-
+	clear_siginfo(&info);
 	info.si_signo = SIGFPE;
 	info.si_code = sicode;
 	info.si_addr = (void __user *)(instruction_pointer(regs) - 4);
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index 87a35364e750..4bcdd0318729 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -882,7 +882,7 @@ asmlinkage void do_fpsimd_exc(unsigned int esr, struct pt_regs *regs)
 			si_code = FPE_FLTRES;
 	}
 
-	memset(&info, 0, sizeof(info));
+	clear_siginfo(&info);
 	info.si_signo = SIGFPE;
 	info.si_code = si_code;
 	info.si_addr = (void __user *)instruction_pointer(regs);
diff --git a/arch/arm64/kernel/sys_compat.c b/arch/arm64/kernel/sys_compat.c
index 93ab57dcfc14..a6109825eeb9 100644
--- a/arch/arm64/kernel/sys_compat.c
+++ b/arch/arm64/kernel/sys_compat.c
@@ -112,6 +112,7 @@ long compat_arm_syscall(struct pt_regs *regs)
 		break;
 	}
 
+	clear_siginfo(&info);
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code  = ILL_ILLTRP;
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index ba964da31a25..7f476586cacc 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -634,6 +634,7 @@ asmlinkage void bad_el0_sync(struct pt_regs *regs, int reason, unsigned int esr)
 	siginfo_t info;
 	void __user *pc = (void __user *)instruction_pointer(regs);
 
+	clear_siginfo(&info);
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code  = ILL_ILLOPC;
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 4165485e8b6e..91c53a7d2575 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -305,11 +305,12 @@ static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *re
 	 */
 	if (user_mode(regs)) {
 		const struct fault_info *inf = esr_to_fault_info(esr);
-		struct siginfo si = {
-			.si_signo	= inf->sig,
-			.si_code	= inf->code,
-			.si_addr	= (void __user *)addr,
-		};
+		struct siginfo si;
+
+		clear_siginfo(&si);
+		si.si_signo	= inf->sig;
+		si.si_code	= inf->code;
+		si.si_addr	= (void __user *)addr;
 
 		__do_user_fault(&si, esr);
 	} else {
@@ -583,6 +584,7 @@ static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 			nmi_exit();
 	}
 
+	clear_siginfo(&info);
 	info.si_signo = inf->sig;
 	info.si_errno = 0;
 	info.si_code  = inf->code;
@@ -687,6 +689,7 @@ asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr,
 		show_pte(addr);
 	}
 
+	clear_siginfo(&info);
 	info.si_signo = inf->sig;
 	info.si_errno = 0;
 	info.si_code  = inf->code;
@@ -729,6 +732,7 @@ asmlinkage void __exception do_sp_pc_abort(unsigned long addr,
 		local_irq_enable();
 	}
 
+	clear_siginfo(&info);
 	info.si_signo = SIGBUS;
 	info.si_errno = 0;
 	info.si_code  = BUS_ADRALN;
@@ -772,7 +776,6 @@ asmlinkage int __exception do_debug_exception(unsigned long addr,
 					      struct pt_regs *regs)
 {
 	const struct fault_info *inf = debug_fault_info + DBG_ESR_EVT(esr);
-	struct siginfo info;
 	int rv;
 
 	/*
@@ -788,6 +791,9 @@ asmlinkage int __exception do_debug_exception(unsigned long addr,
 	if (!inf->fn(addr, esr, regs)) {
 		rv = 1;
 	} else {
+		struct siginfo info;
+
+		clear_siginfo(&info);
 		info.si_signo = inf->sig;
 		info.si_errno = 0;
 		info.si_code  = inf->code;
diff --git a/arch/c6x/kernel/traps.c b/arch/c6x/kernel/traps.c
index 4c1d4b84dd2b..c5feee4542b0 100644
--- a/arch/c6x/kernel/traps.c
+++ b/arch/c6x/kernel/traps.c
@@ -246,6 +246,7 @@ static void do_trap(struct exception_info *except_info, struct pt_regs *regs)
 	unsigned long addr = instruction_pointer(regs);
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	if (except_info->code != TRAP_BRKPT)
 		pr_err("TRAP: %s PC[0x%lx] signo[%d] code[%d]\n",
 		       except_info->kernel_str, regs->pc,
diff --git a/arch/hexagon/kernel/traps.c b/arch/hexagon/kernel/traps.c
index 2942a9204a9a..1ff6a6a7b97c 100644
--- a/arch/hexagon/kernel/traps.c
+++ b/arch/hexagon/kernel/traps.c
@@ -414,6 +414,7 @@ void do_trap0(struct pt_regs *regs)
 		if (user_mode(regs)) {
 			struct siginfo info;
 
+			clear_siginfo(&info);
 			info.si_signo = SIGTRAP;
 			info.si_errno = 0;
 			/*
diff --git a/arch/hexagon/mm/vm_fault.c b/arch/hexagon/mm/vm_fault.c
index 3eec33c5cfd7..2ad92edc877c 100644
--- a/arch/hexagon/mm/vm_fault.c
+++ b/arch/hexagon/mm/vm_fault.c
@@ -56,6 +56,7 @@ void do_page_fault(unsigned long address, long cause, struct pt_regs *regs)
 	const struct exception_table_entry *fixup;
 	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
 
+	clear_siginfo(&info);
 	/*
 	 * If we're in an interrupt or have no user context,
 	 * then must not take the fault.
diff --git a/arch/ia64/kernel/brl_emu.c b/arch/ia64/kernel/brl_emu.c
index 9bcc908bc85e..a61f6c6a36f8 100644
--- a/arch/ia64/kernel/brl_emu.c
+++ b/arch/ia64/kernel/brl_emu.c
@@ -62,6 +62,7 @@ ia64_emulate_brl (struct pt_regs *regs, unsigned long ar_ec)
 	struct illegal_op_return rv;
 	long tmp_taken, unimplemented_address;
 
+	clear_siginfo(&siginfo);
 	rv.fkt = (unsigned long) -1;
 
 	/*
diff --git a/arch/ia64/kernel/signal.c b/arch/ia64/kernel/signal.c
index 54547c7cf8a2..d1234a5ba4c5 100644
--- a/arch/ia64/kernel/signal.c
+++ b/arch/ia64/kernel/signal.c
@@ -153,6 +153,7 @@ ia64_rt_sigreturn (struct sigscratch *scr)
 	return retval;
 
   give_sigsegv:
+	clear_siginfo(&si);
 	si.si_signo = SIGSEGV;
 	si.si_errno = 0;
 	si.si_code = SI_KERNEL;
@@ -236,6 +237,7 @@ force_sigsegv_info (int sig, void __user *addr)
 	unsigned long flags;
 	struct siginfo si;
 
+	clear_siginfo(&si);
 	if (sig == SIGSEGV) {
 		/*
 		 * Acquiring siglock around the sa_handler-update is almost
diff --git a/arch/ia64/kernel/traps.c b/arch/ia64/kernel/traps.c
index 6d4e76a4267f..972873ed1ae5 100644
--- a/arch/ia64/kernel/traps.c
+++ b/arch/ia64/kernel/traps.c
@@ -104,6 +104,7 @@ __kprobes ia64_bad_break (unsigned long break_num, struct pt_regs *regs)
 	int sig, code;
 
 	/* SIGILL, SIGFPE, SIGSEGV, and SIGBUS want these field initialized: */
+	clear_siginfo(&siginfo);
 	siginfo.si_addr = (void __user *) (regs->cr_iip + ia64_psr(regs)->ri);
 	siginfo.si_imm = break_num;
 	siginfo.si_flags = 0;		/* clear __ISR_VALID */
@@ -293,7 +294,6 @@ handle_fpu_swa (int fp_fault, struct pt_regs *regs, unsigned long isr)
 {
 	long exception, bundle[2];
 	unsigned long fault_ip;
-	struct siginfo siginfo;
 
 	fault_ip = regs->cr_iip;
 	if (!fp_fault && (ia64_psr(regs)->ri == 0))
@@ -344,10 +344,13 @@ handle_fpu_swa (int fp_fault, struct pt_regs *regs, unsigned long isr)
 			printk(KERN_ERR "handle_fpu_swa: fp_emulate() returned -1\n");
 			return -1;
 		} else {
+			struct siginfo siginfo;
+
 			/* is next instruction a trap? */
 			if (exception & 2) {
 				ia64_increment_ip(regs);
 			}
+			clear_siginfo(&siginfo);
 			siginfo.si_signo = SIGFPE;
 			siginfo.si_errno = 0;
 			siginfo.si_code = FPE_FIXME;	/* default code */
@@ -372,6 +375,9 @@ handle_fpu_swa (int fp_fault, struct pt_regs *regs, unsigned long isr)
 			return -1;
 		} else if (exception != 0) {
 			/* raise exception */
+			struct siginfo siginfo;
+
+			clear_siginfo(&siginfo);
 			siginfo.si_signo = SIGFPE;
 			siginfo.si_errno = 0;
 			siginfo.si_code = FPE_FIXME;	/* default code */
@@ -420,7 +426,7 @@ ia64_illegal_op_fault (unsigned long ec, long arg1, long arg2, long arg3,
 	if (die_if_kernel(buf, &regs, 0))
 		return rv;
 
-	memset(&si, 0, sizeof(si));
+	clear_siginfo(&si);
 	si.si_signo = SIGILL;
 	si.si_code = ILL_ILLOPC;
 	si.si_addr = (void __user *) (regs.cr_iip + ia64_psr(&regs)->ri);
@@ -434,7 +440,6 @@ ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa,
 	    long arg7, struct pt_regs regs)
 {
 	unsigned long code, error = isr, iip;
-	struct siginfo siginfo;
 	char buf[128];
 	int result, sig;
 	static const char *reason[] = {
@@ -485,6 +490,7 @@ ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa,
 
 	      case 26: /* NaT Consumption */
 		if (user_mode(&regs)) {
+			struct siginfo siginfo;
 			void __user *addr;
 
 			if (((isr >> 4) & 0xf) == 2) {
@@ -499,6 +505,7 @@ ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa,
 				addr = (void __user *) (regs.cr_iip
 							+ ia64_psr(&regs)->ri);
 			}
+			clear_siginfo(&siginfo);
 			siginfo.si_signo = sig;
 			siginfo.si_code = code;
 			siginfo.si_errno = 0;
@@ -515,6 +522,9 @@ ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa,
 
 	      case 31: /* Unsupported Data Reference */
 		if (user_mode(&regs)) {
+			struct siginfo siginfo;
+
+			clear_siginfo(&siginfo);
 			siginfo.si_signo = SIGILL;
 			siginfo.si_code = ILL_ILLOPN;
 			siginfo.si_errno = 0;
@@ -531,6 +541,10 @@ ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa,
 	      case 29: /* Debug */
 	      case 35: /* Taken Branch Trap */
 	      case 36: /* Single Step Trap */
+	      {
+		struct siginfo siginfo;
+
+		clear_siginfo(&siginfo);
 		if (fsys_mode(current, &regs)) {
 			extern char __kernel_syscall_via_break[];
 			/*
@@ -578,11 +592,15 @@ ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa,
 		siginfo.si_isr   = isr;
 		force_sig_info(SIGTRAP, &siginfo, current);
 		return;
+	      }
 
 	      case 32: /* fp fault */
 	      case 33: /* fp trap */
 		result = handle_fpu_swa((vector == 32) ? 1 : 0, &regs, isr);
 		if ((result < 0) || (current->thread.flags & IA64_THREAD_FPEMU_SIGFPE)) {
+			struct siginfo siginfo;
+
+			clear_siginfo(&siginfo);
 			siginfo.si_signo = SIGFPE;
 			siginfo.si_errno = 0;
 			siginfo.si_code = FPE_FLTINV;
@@ -616,6 +634,9 @@ ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa,
 		} else {
 			/* Unimplemented Instr. Address Trap */
 			if (user_mode(&regs)) {
+				struct siginfo siginfo;
+
+				clear_siginfo(&siginfo);
 				siginfo.si_signo = SIGILL;
 				siginfo.si_code = ILL_BADIADDR;
 				siginfo.si_errno = 0;
diff --git a/arch/ia64/kernel/unaligned.c b/arch/ia64/kernel/unaligned.c
index 72e9b4242564..e309f9859acc 100644
--- a/arch/ia64/kernel/unaligned.c
+++ b/arch/ia64/kernel/unaligned.c
@@ -1537,6 +1537,7 @@ ia64_handle_unaligned (unsigned long ifa, struct pt_regs *regs)
 		/* NOT_REACHED */
 	}
   force_sigbus:
+	clear_siginfo(&si);
 	si.si_signo = SIGBUS;
 	si.si_errno = 0;
 	si.si_code = BUS_ADRALN;
diff --git a/arch/ia64/mm/fault.c b/arch/ia64/mm/fault.c
index dfdc152d6737..817fa120645f 100644
--- a/arch/ia64/mm/fault.c
+++ b/arch/ia64/mm/fault.c
@@ -85,7 +85,6 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
 	int signal = SIGSEGV, code = SEGV_MAPERR;
 	struct vm_area_struct *vma, *prev_vma;
 	struct mm_struct *mm = current->mm;
-	struct siginfo si;
 	unsigned long mask;
 	int fault;
 	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
@@ -249,6 +248,9 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
 		return;
 	}
 	if (user_mode(regs)) {
+		struct siginfo si;
+
+		clear_siginfo(&si);
 		si.si_signo = signal;
 		si.si_errno = 0;
 		si.si_code = code;
diff --git a/arch/m68k/kernel/traps.c b/arch/m68k/kernel/traps.c
index c1cc4e99aa94..0a00b476236d 100644
--- a/arch/m68k/kernel/traps.c
+++ b/arch/m68k/kernel/traps.c
@@ -1011,6 +1011,7 @@ asmlinkage void trap_c(struct frame *fp)
 	int vector = (fp->ptregs.vector >> 2) & 0xff;
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	if (fp->ptregs.sr & PS_S) {
 		if (vector == VEC_TRACE) {
 			/* traced a trapping instruction on a 68020/30,
@@ -1163,6 +1164,7 @@ asmlinkage void fpemu_signal(int signal, int code, void *addr)
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_signo = signal;
 	info.si_errno = 0;
 	info.si_code = code;
diff --git a/arch/microblaze/kernel/exceptions.c b/arch/microblaze/kernel/exceptions.c
index e6f338d0496b..443ec1feacb4 100644
--- a/arch/microblaze/kernel/exceptions.c
+++ b/arch/microblaze/kernel/exceptions.c
@@ -65,6 +65,7 @@ void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
 	if (kernel_mode(regs))
 		die("Exception in kernel mode", regs, signr);
 
+	clear_siginfo(&info);
 	info.si_signo = signr;
 	info.si_errno = 0;
 	info.si_code = code;
diff --git a/arch/microblaze/mm/fault.c b/arch/microblaze/mm/fault.c
index f91b30f8aaa8..43d92167012a 100644
--- a/arch/microblaze/mm/fault.c
+++ b/arch/microblaze/mm/fault.c
@@ -88,7 +88,6 @@ void do_page_fault(struct pt_regs *regs, unsigned long address,
 {
 	struct vm_area_struct *vma;
 	struct mm_struct *mm = current->mm;
-	siginfo_t info;
 	int code = SEGV_MAPERR;
 	int is_write = error_code & ESR_S;
 	int fault;
@@ -295,6 +294,9 @@ void do_page_fault(struct pt_regs *regs, unsigned long address,
 do_sigbus:
 	up_read(&mm->mmap_sem);
 	if (user_mode(regs)) {
+		siginfo_t info;
+
+		clear_siginfo(&info);
 		info.si_signo = SIGBUS;
 		info.si_errno = 0;
 		info.si_code = BUS_ADRERR;
diff --git a/arch/mips/mm/fault.c b/arch/mips/mm/fault.c
index 4f8f5bf46977..75392becd933 100644
--- a/arch/mips/mm/fault.c
+++ b/arch/mips/mm/fault.c
@@ -63,6 +63,7 @@ static void __kprobes __do_page_fault(struct pt_regs *regs, unsigned long write,
 		return;
 #endif
 
+	clear_siginfo(&info);
 	info.si_code = SEGV_MAPERR;
 
 	/*
diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c
index 8e9a5b1f6234..46911768f4b5 100644
--- a/arch/nds32/kernel/traps.c
+++ b/arch/nds32/kernel/traps.c
@@ -229,6 +229,7 @@ int bad_syscall(int n, struct pt_regs *regs)
 		return regs->uregs[0];
 	}
 
+	clear_siginfo(&info);
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code = ILL_ILLTRP;
@@ -292,7 +293,7 @@ void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
 	tsk->thread.trap_no = ENTRY_DEBUG_RELATED;
 	tsk->thread.error_code = error_code;
 
-	memset(&info, 0, sizeof(info));
+	clear_siginfo(&info);
 	info.si_signo = SIGTRAP;
 	info.si_code = si_code;
 	info.si_addr = (void __user *)instruction_pointer(regs);
diff --git a/arch/nds32/mm/fault.c b/arch/nds32/mm/fault.c
index 3a246fb8098c..876ee01ff80a 100644
--- a/arch/nds32/mm/fault.c
+++ b/arch/nds32/mm/fault.c
@@ -77,6 +77,7 @@ void do_page_fault(unsigned long entry, unsigned long addr,
 	unsigned int mask = VM_READ | VM_WRITE | VM_EXEC;
 	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
 
+	clear_siginfo(&info);
 	error_code = error_code & (ITYPE_mskINST | ITYPE_mskETYPE);
 	tsk = current;
 	mm = tsk->mm;
diff --git a/arch/nios2/kernel/traps.c b/arch/nios2/kernel/traps.c
index 8184e7d6b385..a69861d3e1a3 100644
--- a/arch/nios2/kernel/traps.c
+++ b/arch/nios2/kernel/traps.c
@@ -28,6 +28,7 @@ static void _send_sig(int signo, int code, unsigned long addr)
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_signo = signo;
 	info.si_errno = 0;
 	info.si_code = code;
diff --git a/arch/openrisc/kernel/traps.c b/arch/openrisc/kernel/traps.c
index 113c175fe469..1610b1d65a11 100644
--- a/arch/openrisc/kernel/traps.c
+++ b/arch/openrisc/kernel/traps.c
@@ -251,7 +251,7 @@ void __init trap_init(void)
 asmlinkage void do_trap(struct pt_regs *regs, unsigned long address)
 {
 	siginfo_t info;
-	memset(&info, 0, sizeof(info));
+	clear_siginfo(&info);
 	info.si_signo = SIGTRAP;
 	info.si_code = TRAP_TRACE;
 	info.si_addr = (void *)address;
@@ -266,6 +266,7 @@ asmlinkage void do_unaligned_access(struct pt_regs *regs, unsigned long address)
 
 	if (user_mode(regs)) {
 		/* Send a SIGBUS */
+		clear_siginfo(&info);
 		info.si_signo = SIGBUS;
 		info.si_errno = 0;
 		info.si_code = BUS_ADRALN;
@@ -285,6 +286,7 @@ asmlinkage void do_bus_fault(struct pt_regs *regs, unsigned long address)
 
 	if (user_mode(regs)) {
 		/* Send a SIGBUS */
+		clear_siginfo(&info);
 		info.si_signo = SIGBUS;
 		info.si_errno = 0;
 		info.si_code = BUS_ADRERR;
@@ -485,6 +487,7 @@ asmlinkage void do_illegal_instruction(struct pt_regs *regs,
 
 	if (user_mode(regs)) {
 		/* Send a SIGILL */
+		clear_siginfo(&info);
 		info.si_signo = SIGILL;
 		info.si_errno = 0;
 		info.si_code = ILL_ILLOPC;
diff --git a/arch/openrisc/mm/fault.c b/arch/openrisc/mm/fault.c
index d0021dfae20a..68be33e4ae17 100644
--- a/arch/openrisc/mm/fault.c
+++ b/arch/openrisc/mm/fault.c
@@ -56,6 +56,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long address,
 	int fault;
 	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
 
+	clear_siginfo(&info);
 	tsk = current;
 
 	/*
diff --git a/arch/parisc/kernel/ptrace.c b/arch/parisc/kernel/ptrace.c
index 1a2be6e639b5..b1c12ceb1c88 100644
--- a/arch/parisc/kernel/ptrace.c
+++ b/arch/parisc/kernel/ptrace.c
@@ -90,6 +90,7 @@ void user_enable_single_step(struct task_struct *task)
 		ptrace_disable(task);
 		/* Don't wake up the task, but let the
 		   parent know something happened. */
+		clear_siginfo(&si);
 		si.si_code = TRAP_TRACE;
 		si.si_addr = (void __user *) (task_regs(task)->iaoq[0] & ~3);
 		si.si_signo = SIGTRAP;
diff --git a/arch/parisc/kernel/traps.c b/arch/parisc/kernel/traps.c
index 68e671a11987..98f9f2f85940 100644
--- a/arch/parisc/kernel/traps.c
+++ b/arch/parisc/kernel/traps.c
@@ -299,6 +299,7 @@ static void handle_gdb_break(struct pt_regs *regs, int wot)
 {
 	struct siginfo si;
 
+	clear_siginfo(&si);
 	si.si_signo = SIGTRAP;
 	si.si_errno = 0;
 	si.si_code = wot;
@@ -489,6 +490,7 @@ void notrace handle_interruption(int code, struct pt_regs *regs)
 	unsigned long fault_space = 0;
 	struct siginfo si;
 
+	clear_siginfo(&si);
 	if (code == 1)
 	    pdc_console_restart();  /* switch back to pdc if HPMC */
 	else
diff --git a/arch/parisc/kernel/unaligned.c b/arch/parisc/kernel/unaligned.c
index e36f7b75ab07..30b7c7f6c471 100644
--- a/arch/parisc/kernel/unaligned.c
+++ b/arch/parisc/kernel/unaligned.c
@@ -455,6 +455,7 @@ void handle_unaligned(struct pt_regs *regs)
 	struct siginfo si;
 	register int flop=0;	/* true if this is a flop */
 
+	clear_siginfo(&si);
 	__inc_irq_stat(irq_unaligned_count);
 
 	/* log a message with pacing */
diff --git a/arch/parisc/math-emu/driver.c b/arch/parisc/math-emu/driver.c
index 2fb59d2e2b29..0d10efb53361 100644
--- a/arch/parisc/math-emu/driver.c
+++ b/arch/parisc/math-emu/driver.c
@@ -93,6 +93,7 @@ handle_fpe(struct pt_regs *regs)
 	 */
 	__u64 frcopy[36];
 
+	clear_siginfo(&si);
 	memcpy(frcopy, regs->fr, sizeof regs->fr);
 	frcopy[32] = 0;
 
diff --git a/arch/parisc/mm/fault.c b/arch/parisc/mm/fault.c
index e247edbca68e..657b35096bd8 100644
--- a/arch/parisc/mm/fault.c
+++ b/arch/parisc/mm/fault.c
@@ -356,6 +356,7 @@ void do_page_fault(struct pt_regs *regs, unsigned long code,
 		struct siginfo si;
 		unsigned int lsb = 0;
 
+		clear_siginfo(&si);
 		switch (code) {
 		case 15:	/* Data TLB miss fault/Data page fault */
 			/* send SIGSEGV when outside of vma */
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 1237f13fed51..26ea9793d290 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -632,6 +632,7 @@ void do_break (struct pt_regs *regs, unsigned long address,
 	hw_breakpoint_disable();
 
 	/* Deliver the signal to userspace */
+	clear_siginfo(&info);
 	info.si_signo = SIGTRAP;
 	info.si_errno = 0;
 	info.si_code = TRAP_HWBKPT;
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 0904492e7032..087855caf6a9 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -296,7 +296,6 @@ NOKPROBE_SYMBOL(die);
 void user_single_step_siginfo(struct task_struct *tsk,
 				struct pt_regs *regs, siginfo_t *info)
 {
-	memset(info, 0, sizeof(*info));
 	info->si_signo = SIGTRAP;
 	info->si_code = TRAP_TRACE;
 	info->si_addr = (void __user *)regs->nip;
@@ -334,7 +333,7 @@ void _exception_pkey(int signr, struct pt_regs *regs, int code,
 	 */
 	thread_pkey_regs_save(&current->thread);
 
-	memset(&info, 0, sizeof(info));
+	clear_siginfo(&info);
 	info.si_signo = signr;
 	info.si_code = code;
 	info.si_addr = (void __user *) addr;
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index c01d627e687a..ef268d5d9db7 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -168,6 +168,7 @@ static int do_sigbus(struct pt_regs *regs, unsigned long address,
 		return SIGBUS;
 
 	current->thread.trap_nr = BUS_ADRERR;
+	clear_siginfo(&info);
 	info.si_signo = SIGBUS;
 	info.si_errno = 0;
 	info.si_code = BUS_ADRERR;
diff --git a/arch/powerpc/platforms/cell/spufs/fault.c b/arch/powerpc/platforms/cell/spufs/fault.c
index 870c0a82d560..1e002e94d0f6 100644
--- a/arch/powerpc/platforms/cell/spufs/fault.c
+++ b/arch/powerpc/platforms/cell/spufs/fault.c
@@ -44,7 +44,7 @@ static void spufs_handle_event(struct spu_context *ctx,
 		return;
 	}
 
-	memset(&info, 0, sizeof(info));
+	clear_siginfo(&info);
 
 	switch (type) {
 	case SPE_EVENT_INVALID_DMA:
diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
index 93132cb59184..48aa6471cede 100644
--- a/arch/riscv/kernel/traps.c
+++ b/arch/riscv/kernel/traps.c
@@ -68,6 +68,7 @@ static inline void do_trap_siginfo(int signo, int code,
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_signo = signo;
 	info.si_errno = 0;
 	info.si_code = code;
diff --git a/arch/s390/kernel/traps.c b/arch/s390/kernel/traps.c
index a5297a22bc1e..3ba649d8aa5a 100644
--- a/arch/s390/kernel/traps.c
+++ b/arch/s390/kernel/traps.c
@@ -47,6 +47,7 @@ void do_report_trap(struct pt_regs *regs, int si_signo, int si_code, char *str)
 	siginfo_t info;
 
 	if (user_mode(regs)) {
+		clear_siginfo(&info);
 		info.si_signo = si_signo;
 		info.si_errno = 0;
 		info.si_code = si_code;
@@ -86,6 +87,7 @@ void do_per_trap(struct pt_regs *regs)
 		return;
 	if (!current->ptrace)
 		return;
+	clear_siginfo(&info);
 	info.si_signo = SIGTRAP;
 	info.si_errno = 0;
 	info.si_code = TRAP_HWBKPT;
@@ -165,7 +167,6 @@ void translation_exception(struct pt_regs *regs)
 
 void illegal_op(struct pt_regs *regs)
 {
-	siginfo_t info;
         __u8 opcode[6];
 	__u16 __user *location;
 	int is_uprobe_insn = 0;
@@ -178,6 +179,8 @@ void illegal_op(struct pt_regs *regs)
 			return;
 		if (*((__u16 *) opcode) == S390_BREAKPOINT_U16) {
 			if (current->ptrace) {
+				siginfo_t info;
+				clear_siginfo(&info);
 				info.si_signo = SIGTRAP;
 				info.si_errno = 0;
 				info.si_code = TRAP_BRKPT;
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 93faeca52284..b3ff0e8e5860 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -268,6 +268,7 @@ static noinline void do_sigsegv(struct pt_regs *regs, int si_code)
 	struct siginfo si;
 
 	report_user_fault(regs, SIGSEGV, 1);
+	clear_siginfo(&si);
 	si.si_signo = SIGSEGV;
 	si.si_errno = 0;
 	si.si_code = si_code;
@@ -323,6 +324,7 @@ static noinline void do_sigbus(struct pt_regs *regs)
 	 * Send a sigbus, regardless of whether we were in kernel
 	 * or user mode.
 	 */
+	clear_siginfo(&si);
 	si.si_signo = SIGBUS;
 	si.si_errno = 0;
 	si.si_code = BUS_ADRERR;
diff --git a/arch/sh/kernel/traps_32.c b/arch/sh/kernel/traps_32.c
index b3770bb26211..e85e59c3d6df 100644
--- a/arch/sh/kernel/traps_32.c
+++ b/arch/sh/kernel/traps_32.c
@@ -537,6 +537,7 @@ asmlinkage void do_address_error(struct pt_regs *regs,
 		       "access (PC %lx PR %lx)\n", current->comm, regs->pc,
 		       regs->pr);
 
+		clear_siginfo(&info);
 		info.si_signo = SIGBUS;
 		info.si_errno = 0;
 		info.si_code = si_code;
@@ -600,6 +601,7 @@ asmlinkage void do_divide_error(unsigned long r4)
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	switch (r4) {
 	case TRAP_DIVZERO_ERROR:
 		info.si_code = FPE_INTDIV;
diff --git a/arch/sh/math-emu/math.c b/arch/sh/math-emu/math.c
index c86f4360c6ce..d6d2213df078 100644
--- a/arch/sh/math-emu/math.c
+++ b/arch/sh/math-emu/math.c
@@ -560,6 +560,7 @@ static int ieee_fpe_handler(struct pt_regs *regs)
 				~(FPSCR_CAUSE_MASK | FPSCR_FLAG_MASK);
 			task_thread_info(tsk)->status |= TS_USEDFPU;
 		} else {
+			clear_siginfo(&info);
 			info.si_signo = SIGFPE;
 			info.si_errno = 0;
 			info.si_code = FPE_FLTINV;
diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c
index 6fd1bf7481c7..4c98b6f20e02 100644
--- a/arch/sh/mm/fault.c
+++ b/arch/sh/mm/fault.c
@@ -44,6 +44,7 @@ force_sig_info_fault(int si_signo, int si_code, unsigned long address,
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_signo	= si_signo;
 	info.si_errno	= 0;
 	info.si_code	= si_code;
diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c
index 454a8af28f13..2219e55206b4 100644
--- a/arch/sparc/kernel/process_64.c
+++ b/arch/sparc/kernel/process_64.c
@@ -520,6 +520,7 @@ static void stack_unaligned(unsigned long sp)
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_signo = SIGBUS;
 	info.si_errno = 0;
 	info.si_code = BUS_ADRALN;
diff --git a/arch/sparc/kernel/sys_sparc_32.c b/arch/sparc/kernel/sys_sparc_32.c
index e8c3cb6b6d08..00f6353fe435 100644
--- a/arch/sparc/kernel/sys_sparc_32.c
+++ b/arch/sparc/kernel/sys_sparc_32.c
@@ -152,6 +152,7 @@ sparc_breakpoint (struct pt_regs *regs)
 #ifdef DEBUG_SPARC_BREAKPOINT
         printk ("TRAP: Entering kernel PC=%x, nPC=%x\n", regs->pc, regs->npc);
 #endif
+	clear_siginfo(&info);
 	info.si_signo = SIGTRAP;
 	info.si_errno = 0;
 	info.si_code = TRAP_BRKPT;
diff --git a/arch/sparc/kernel/traps_32.c b/arch/sparc/kernel/traps_32.c
index 33cd35bf3dc8..03e522274b8b 100644
--- a/arch/sparc/kernel/traps_32.c
+++ b/arch/sparc/kernel/traps_32.c
@@ -104,6 +104,7 @@ void do_hw_interrupt(struct pt_regs *regs, unsigned long type)
 	if(regs->psr & PSR_PS)
 		die_if_kernel("Kernel bad trap", regs);
 
+	clear_siginfo(&info);
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code = ILL_ILLTRP;
@@ -124,6 +125,7 @@ void do_illegal_instruction(struct pt_regs *regs, unsigned long pc, unsigned lon
 	       regs->pc, *(unsigned long *)regs->pc);
 #endif
 
+	clear_siginfo(&info);
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code = ILL_ILLOPC;
@@ -139,6 +141,7 @@ void do_priv_instruction(struct pt_regs *regs, unsigned long pc, unsigned long n
 
 	if(psr & PSR_PS)
 		die_if_kernel("Penguin instruction from Penguin mode??!?!", regs);
+	clear_siginfo(&info);
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code = ILL_PRVOPC;
@@ -165,6 +168,7 @@ void do_memaccess_unaligned(struct pt_regs *regs, unsigned long pc, unsigned lon
 	instruction_dump ((unsigned long *) regs->pc);
 	printk ("do_MNA!\n");
 #endif
+	clear_siginfo(&info);
 	info.si_signo = SIGBUS;
 	info.si_errno = 0;
 	info.si_code = BUS_ADRALN;
@@ -303,6 +307,7 @@ void do_fpe_trap(struct pt_regs *regs, unsigned long pc, unsigned long npc,
 	}
 
 	fsr = fpt->thread.fsr;
+	clear_siginfo(&info);
 	info.si_signo = SIGFPE;
 	info.si_errno = 0;
 	info.si_addr = (void __user *)pc;
@@ -336,6 +341,7 @@ void handle_tag_overflow(struct pt_regs *regs, unsigned long pc, unsigned long n
 
 	if(psr & PSR_PS)
 		die_if_kernel("Penguin overflow trap from kernel mode", regs);
+	clear_siginfo(&info);
 	info.si_signo = SIGEMT;
 	info.si_errno = 0;
 	info.si_code = EMT_TAGOVF;
@@ -365,6 +371,7 @@ 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
+	clear_siginfo(&info);
 	info.si_signo = SIGBUS;
 	info.si_errno = 0;
 	info.si_code = BUS_OBJERR;
@@ -378,6 +385,7 @@ void handle_cp_disabled(struct pt_regs *regs, unsigned long pc, unsigned long np
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code = ILL_COPROC;
@@ -395,6 +403,7 @@ void handle_cp_exception(struct pt_regs *regs, unsigned long pc, unsigned long n
 	printk("Co-Processor Exception at PC %08lx NPC %08lx PSR %08lx\n",
 	       pc, npc, psr);
 #endif
+	clear_siginfo(&info);
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code = ILL_COPROC;
@@ -408,6 +417,7 @@ void handle_hw_divzero(struct pt_regs *regs, unsigned long pc, unsigned long npc
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_signo = SIGFPE;
 	info.si_errno = 0;
 	info.si_code = FPE_INTDIV;
diff --git a/arch/sparc/kernel/traps_64.c b/arch/sparc/kernel/traps_64.c
index e81072ac52c3..b485b49b87a8 100644
--- a/arch/sparc/kernel/traps_64.c
+++ b/arch/sparc/kernel/traps_64.c
@@ -107,6 +107,7 @@ void bad_trap(struct pt_regs *regs, long lvl)
 		regs->tpc &= 0xffffffff;
 		regs->tnpc &= 0xffffffff;
 	}
+	clear_siginfo(&info);
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code = ILL_ILLTRP;
@@ -206,6 +207,7 @@ void spitfire_insn_access_exception(struct pt_regs *regs, unsigned long sfsr, un
 		regs->tpc &= 0xffffffff;
 		regs->tnpc &= 0xffffffff;
 	}
+	clear_siginfo(&info);
 	info.si_signo = SIGSEGV;
 	info.si_errno = 0;
 	info.si_code = SEGV_MAPERR;
@@ -247,6 +249,7 @@ void sun4v_insn_access_exception(struct pt_regs *regs, unsigned long addr, unsig
 		regs->tpc &= 0xffffffff;
 		regs->tnpc &= 0xffffffff;
 	}
+	clear_siginfo(&info);
 	info.si_signo = SIGSEGV;
 	info.si_errno = 0;
 	info.si_code = SEGV_MAPERR;
@@ -338,6 +341,7 @@ void spitfire_data_access_exception(struct pt_regs *regs, unsigned long sfsr, un
 	if (is_no_fault_exception(regs))
 		return;
 
+	clear_siginfo(&info);
 	info.si_signo = SIGSEGV;
 	info.si_errno = 0;
 	info.si_code = SEGV_MAPERR;
@@ -595,6 +599,7 @@ static void spitfire_ue_log(unsigned long afsr, unsigned long afar, unsigned lon
 		regs->tpc &= 0xffffffff;
 		regs->tnpc &= 0xffffffff;
 	}
+	clear_siginfo(&info);
 	info.si_signo = SIGBUS;
 	info.si_errno = 0;
 	info.si_code = BUS_OBJERR;
@@ -2211,6 +2216,7 @@ bool sun4v_nonresum_error_user_handled(struct pt_regs *regs,
 				addr += PAGE_SIZE;
 			}
 		}
+		clear_siginfo(&info);
 		info.si_signo = SIGKILL;
 		info.si_errno = 0;
 		info.si_trapno = 0;
@@ -2221,6 +2227,7 @@ bool sun4v_nonresum_error_user_handled(struct pt_regs *regs,
 	if (attrs & SUN4V_ERR_ATTRS_PIO) {
 		siginfo_t info;
 
+		clear_siginfo(&info);
 		info.si_signo = SIGBUS;
 		info.si_code = BUS_ADRERR;
 		info.si_addr = (void __user *)sun4v_get_vaddr(regs);
@@ -2368,6 +2375,7 @@ static void do_fpe_common(struct pt_regs *regs)
 			regs->tpc &= 0xffffffff;
 			regs->tnpc &= 0xffffffff;
 		}
+		clear_siginfo(&info);
 		info.si_signo = SIGFPE;
 		info.si_errno = 0;
 		info.si_addr = (void __user *)regs->tpc;
@@ -2440,6 +2448,7 @@ void do_tof(struct pt_regs *regs)
 		regs->tpc &= 0xffffffff;
 		regs->tnpc &= 0xffffffff;
 	}
+	clear_siginfo(&info);
 	info.si_signo = SIGEMT;
 	info.si_errno = 0;
 	info.si_code = EMT_TAGOVF;
@@ -2465,6 +2474,7 @@ void do_div0(struct pt_regs *regs)
 		regs->tpc &= 0xffffffff;
 		regs->tnpc &= 0xffffffff;
 	}
+	clear_siginfo(&info);
 	info.si_signo = SIGFPE;
 	info.si_errno = 0;
 	info.si_code = FPE_INTDIV;
@@ -2666,6 +2676,7 @@ void do_illegal_instruction(struct pt_regs *regs)
 			}
 		}
 	}
+	clear_siginfo(&info);
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code = ILL_ILLOPC;
@@ -2692,6 +2703,7 @@ void mem_address_unaligned(struct pt_regs *regs, unsigned long sfar, unsigned lo
 	if (is_no_fault_exception(regs))
 		return;
 
+	clear_siginfo(&info);
 	info.si_signo = SIGBUS;
 	info.si_errno = 0;
 	info.si_code = BUS_ADRALN;
@@ -2717,6 +2729,7 @@ void sun4v_do_mna(struct pt_regs *regs, unsigned long addr, unsigned long type_c
 	if (is_no_fault_exception(regs))
 		return;
 
+	clear_siginfo(&info);
 	info.si_signo = SIGBUS;
 	info.si_errno = 0;
 	info.si_code = BUS_ADRALN;
@@ -2785,6 +2798,7 @@ void do_privop(struct pt_regs *regs)
 		regs->tpc &= 0xffffffff;
 		regs->tnpc &= 0xffffffff;
 	}
+	clear_siginfo(&info);
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code = ILL_PRVOPC;
diff --git a/arch/sparc/kernel/unaligned_32.c b/arch/sparc/kernel/unaligned_32.c
index 7642d7e4f0d9..0e4cf7217413 100644
--- a/arch/sparc/kernel/unaligned_32.c
+++ b/arch/sparc/kernel/unaligned_32.c
@@ -313,6 +313,7 @@ static void user_mna_trap_fault(struct pt_regs *regs, unsigned int insn)
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_signo = SIGBUS;
 	info.si_errno = 0;
 	info.si_code = BUS_ADRALN;
diff --git a/arch/sparc/mm/fault_32.c b/arch/sparc/mm/fault_32.c
index a8103a84b4ac..2deb586665b9 100644
--- a/arch/sparc/mm/fault_32.c
+++ b/arch/sparc/mm/fault_32.c
@@ -129,6 +129,7 @@ static void __do_fault_siginfo(int code, int sig, struct pt_regs *regs,
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_signo = sig;
 	info.si_code = code;
 	info.si_errno = 0;
diff --git a/arch/sparc/mm/fault_64.c b/arch/sparc/mm/fault_64.c
index 41363f46797b..46ccff95d10e 100644
--- a/arch/sparc/mm/fault_64.c
+++ b/arch/sparc/mm/fault_64.c
@@ -172,6 +172,7 @@ static void do_fault_siginfo(int code, int sig, struct pt_regs *regs,
 	unsigned long addr;
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_code = code;
 	info.si_signo = sig;
 	info.si_errno = 0;
diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c
index b2b02df9896e..d4d38520c4c6 100644
--- a/arch/um/kernel/trap.c
+++ b/arch/um/kernel/trap.c
@@ -164,6 +164,7 @@ static void bad_segv(struct faultinfo fi, unsigned long ip)
 {
 	struct siginfo si;
 
+	clear_siginfo(&si);
 	si.si_signo = SIGSEGV;
 	si.si_code = SEGV_ACCERR;
 	si.si_addr = (void __user *) FAULT_ADDRESS(fi);
@@ -220,6 +221,7 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user,
 	int is_write = FAULT_WRITE(fi);
 	unsigned long address = FAULT_ADDRESS(fi);
 
+	clear_siginfo(&si);
 	if (!is_user && regs)
 		current->thread.segv_regs = container_of(regs, struct pt_regs, regs);
 
diff --git a/arch/unicore32/kernel/fpu-ucf64.c b/arch/unicore32/kernel/fpu-ucf64.c
index 12c8c9527b8e..d785955e1c29 100644
--- a/arch/unicore32/kernel/fpu-ucf64.c
+++ b/arch/unicore32/kernel/fpu-ucf64.c
@@ -56,7 +56,7 @@ void ucf64_raise_sigfpe(unsigned int sicode, struct pt_regs *regs)
 {
 	siginfo_t info;
 
-	memset(&info, 0, sizeof(info));
+	clear_siginfo(&info);
 
 	info.si_signo = SIGFPE;
 	info.si_code = sicode;
diff --git a/arch/unicore32/mm/fault.c b/arch/unicore32/mm/fault.c
index bbefcc46a45e..381473412937 100644
--- a/arch/unicore32/mm/fault.c
+++ b/arch/unicore32/mm/fault.c
@@ -125,6 +125,7 @@ static void __do_user_fault(struct task_struct *tsk, unsigned long addr,
 	tsk->thread.address = addr;
 	tsk->thread.error_code = fsr;
 	tsk->thread.trap_no = 14;
+	clear_siginfo(&si);
 	si.si_signo = sig;
 	si.si_errno = 0;
 	si.si_code = code;
@@ -472,6 +473,7 @@ asmlinkage void do_DataAbort(unsigned long addr, unsigned int fsr,
 	printk(KERN_ALERT "Unhandled fault: %s (0x%03x) at 0x%08lx\n",
 	       inf->name, fsr, addr);
 
+	clear_siginfo(&info);
 	info.si_signo = inf->sig;
 	info.si_errno = 0;
 	info.si_code = inf->code;
@@ -491,6 +493,7 @@ asmlinkage void do_PrefetchAbort(unsigned long addr,
 	printk(KERN_ALERT "Unhandled prefetch abort: %s (0x%03x) at 0x%08lx\n",
 	       inf->name, ifsr, addr);
 
+	clear_siginfo(&info);
 	info.si_signo = inf->sig;
 	info.si_errno = 0;
 	info.si_code = inf->code;
diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c
index 70b7845434cb..7782cdbcd67d 100644
--- a/arch/x86/entry/vsyscall/vsyscall_64.c
+++ b/arch/x86/entry/vsyscall/vsyscall_64.c
@@ -107,7 +107,7 @@ static bool write_ok_or_segv(unsigned long ptr, size_t size)
 		thread->cr2		= ptr;
 		thread->trap_nr		= X86_TRAP_PF;
 
-		memset(&info, 0, sizeof(info));
+		clear_siginfo(&info);
 		info.si_signo		= SIGSEGV;
 		info.si_errno		= 0;
 		info.si_code		= SEGV_MAPERR;
diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index ed5c4cdf0a34..e2ee403865eb 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -1377,7 +1377,6 @@ static void fill_sigtrap_info(struct task_struct *tsk,
 	tsk->thread.trap_nr = X86_TRAP_DB;
 	tsk->thread.error_code = error_code;
 
-	memset(info, 0, sizeof(*info));
 	info->si_signo = SIGTRAP;
 	info->si_code = si_code;
 	info->si_addr = user_mode(regs) ? (void __user *)regs->ip : NULL;
@@ -1395,6 +1394,7 @@ void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
 {
 	struct siginfo info;
 
+	clear_siginfo(&info);
 	fill_sigtrap_info(tsk, regs, error_code, si_code, &info);
 	/* Send us the fake SIGTRAP */
 	force_sig_info(SIGTRAP, &info, tsk);
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 03f3d7695dac..a535dd64de63 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -299,6 +299,7 @@ static void do_error_trap(struct pt_regs *regs, long error_code, char *str,
 	if (notify_die(DIE_TRAP, str, regs, error_code, trapnr, signr) !=
 			NOTIFY_STOP) {
 		cond_local_irq_enable(regs);
+		clear_siginfo(&info);
 		do_trap(trapnr, signr, str, regs, error_code,
 			fill_trap_info(regs, signr, trapnr, &info));
 	}
@@ -854,6 +855,7 @@ static void math_error(struct pt_regs *regs, int error_code, int trapnr)
 
 	task->thread.trap_nr	= trapnr;
 	task->thread.error_code = error_code;
+	clear_siginfo(&info);
 	info.si_signo		= SIGFPE;
 	info.si_errno		= 0;
 	info.si_addr		= (void __user *)uprobe_get_trap_addr(regs);
@@ -929,6 +931,7 @@ dotraplinkage void do_iret_error(struct pt_regs *regs, long error_code)
 	RCU_LOCKDEP_WARN(!rcu_is_watching(), "entry code didn't wake RCU");
 	local_irq_enable();
 
+	clear_siginfo(&info);
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code = ILL_BADSTK;
diff --git a/arch/x86/kernel/umip.c b/arch/x86/kernel/umip.c
index f44ce0fb3583..ff20b35e98dd 100644
--- a/arch/x86/kernel/umip.c
+++ b/arch/x86/kernel/umip.c
@@ -278,6 +278,7 @@ static void force_sig_info_umip_fault(void __user *addr, struct pt_regs *regs)
 	tsk->thread.error_code	= X86_PF_USER | X86_PF_WRITE;
 	tsk->thread.trap_nr	= X86_TRAP_PF;
 
+	clear_siginfo(&info);
 	info.si_signo	= SIGSEGV;
 	info.si_errno	= 0;
 	info.si_code	= SEGV_MAPERR;
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 8494dbae41b9..d634f0332c0f 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -3007,6 +3007,7 @@ static void kvm_send_hwpoison_signal(unsigned long address, struct task_struct *
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_signo	= SIGBUS;
 	info.si_errno	= 0;
 	info.si_code	= BUS_MCEERR_AR;
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 73bd8c95ac71..2a5a2920203d 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -209,6 +209,7 @@ force_sig_info_fault(int si_signo, int si_code, unsigned long address,
 	unsigned lsb = 0;
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_signo	= si_signo;
 	info.si_errno	= 0;
 	info.si_code	= si_code;
diff --git a/arch/xtensa/kernel/traps.c b/arch/xtensa/kernel/traps.c
index 32c5207f1226..51771929f341 100644
--- a/arch/xtensa/kernel/traps.c
+++ b/arch/xtensa/kernel/traps.c
@@ -334,6 +334,7 @@ do_unaligned_user (struct pt_regs *regs)
 			    "(pid = %d, pc = %#010lx)\n",
 			    regs->excvaddr, current->comm,
 			    task_pid_nr(current), regs->pc);
+	clear_siginfo(&info);
 	info.si_signo = SIGBUS;
 	info.si_errno = 0;
 	info.si_code = BUS_ADRALN;
diff --git a/arch/xtensa/mm/fault.c b/arch/xtensa/mm/fault.c
index 8b9b6f44bb06..f9323a3e61ce 100644
--- a/arch/xtensa/mm/fault.c
+++ b/arch/xtensa/mm/fault.c
@@ -45,6 +45,7 @@ void do_page_fault(struct pt_regs *regs)
 	int fault;
 	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
 
+	clear_siginfo(&info);
 	info.si_code = SEGV_MAPERR;
 
 	/* We fault-in kernel-space virtual memory on-demand. The
diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
index 919b2a0b0307..037bf0ef1ae9 100644
--- a/include/linux/ptrace.h
+++ b/include/linux/ptrace.h
@@ -345,7 +345,6 @@ extern void user_single_step_siginfo(struct task_struct *tsk,
 static inline void user_single_step_siginfo(struct task_struct *tsk,
 				struct pt_regs *regs, siginfo_t *info)
 {
-	memset(info, 0, sizeof(*info));
 	info->si_signo = SIGTRAP;
 }
 #endif
diff --git a/include/linux/tracehook.h b/include/linux/tracehook.h
index 26c152122a42..4a8841963c2e 100644
--- a/include/linux/tracehook.h
+++ b/include/linux/tracehook.h
@@ -124,6 +124,7 @@ static inline void tracehook_report_syscall_exit(struct pt_regs *regs, int step)
 {
 	if (step) {
 		siginfo_t info;
+		clear_siginfo(&info);
 		user_single_step_siginfo(current, regs, &info);
 		force_sig_info(SIGTRAP, &info, current);
 		return;
diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index 7f6a944db23d..8d90de213ce9 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -1401,6 +1401,7 @@ static void kvm_send_hwpoison_signal(unsigned long address,
 {
 	siginfo_t info;
 
+	clear_siginfo(&info);
 	info.si_signo   = SIGBUS;
 	info.si_errno   = 0;
 	info.si_code    = BUS_MCEERR_AR;
-- 
2.14.1

[REVIEW][PATCH 07/17] signal: Reduce copy_siginfo_to_user to just copy_to_user

[Eric W. Biederman]

Now that every instance of struct siginfo is now initialized it is no
longer necessary to copy struct siginfo piece by piece to userspace
but instead the entire structure can be copied.

As well as making the code simpler and more efficient this means that
copy_sinfo_to_user no longer cares which union member of struct
siginfo is in use.

In practice this means that all 32bit architectures that define
FPE_FIXME will handle properly send SI_USER when kill(SIGFPE) is sent.
While still performing their historic architectural brokenness when 0
is used a floating pointer signal.  This matches the current behavior
of 64bit architectures that define FPE_FIXME who get lucky and an
overloaded SI_USER has continuted to work through copy_siginfo_to_user
because the 8 byte si_addr occupies the same bytes in struct siginfo
as the 4 byte si_pid and the 4 byte si_uid.

Problematic architectures still need to fix their ABI so that signalfd
and 32bit compat code will work properly.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 kernel/signal.c | 84 ++-------------------------------------------------------
 1 file changed, 2 insertions(+), 82 deletions(-)

diff --git a/kernel/signal.c b/kernel/signal.c
index d4ccea599692..d56f4d496c89 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2850,89 +2850,9 @@ enum siginfo_layout siginfo_layout(int sig, int si_code)
 
 int copy_siginfo_to_user(siginfo_t __user *to, const siginfo_t *from)
 {
-	int err;
-
-	if (!access_ok (VERIFY_WRITE, to, sizeof(siginfo_t)))
+	if (copy_to_user(to, from , sizeof(struct siginfo)))
 		return -EFAULT;
-	if (from->si_code < 0)
-		return __copy_to_user(to, from, sizeof(siginfo_t))
-			? -EFAULT : 0;
-	/*
-	 * If you change siginfo_t structure, please be sure
-	 * this code is fixed accordingly.
-	 * Please remember to update the signalfd_copyinfo() function
-	 * inside fs/signalfd.c too, in case siginfo_t changes.
-	 * It should never copy any pad contained in the structure
-	 * to avoid security leaks, but must copy the generic
-	 * 3 ints plus the relevant union member.
-	 */
-	err = __put_user(from->si_signo, &to->si_signo);
-	err |= __put_user(from->si_errno, &to->si_errno);
-	err |= __put_user(from->si_code, &to->si_code);
-	switch (siginfo_layout(from->si_signo, from->si_code)) {
-	case SIL_KILL:
-		err |= __put_user(from->si_pid, &to->si_pid);
-		err |= __put_user(from->si_uid, &to->si_uid);
-		break;
-	case SIL_TIMER:
-		/* Unreached SI_TIMER is negative */
-		break;
-	case SIL_POLL:
-		err |= __put_user(from->si_band, &to->si_band);
-		err |= __put_user(from->si_fd, &to->si_fd);
-		break;
-	case SIL_FAULT:
-		err |= __put_user(from->si_addr, &to->si_addr);
-#ifdef __ARCH_SI_TRAPNO
-		err |= __put_user(from->si_trapno, &to->si_trapno);
-#endif
-#ifdef __ia64__
-		err |= __put_user(from->si_imm, &to->si_imm);
-		err |= __put_user(from->si_flags, &to->si_flags);
-		err |= __put_user(from->si_isr, &to->si_isr);
-#endif
-		/*
-		 * Other callers might not initialize the si_lsb field,
-		 * so check explicitly for the right codes here.
-		 */
-#ifdef BUS_MCEERR_AR
-		if (from->si_signo == SIGBUS && from->si_code == BUS_MCEERR_AR)
-			err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb);
-#endif
-#ifdef BUS_MCEERR_AO
-		if (from->si_signo == SIGBUS && from->si_code == BUS_MCEERR_AO)
-			err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb);
-#endif
-#ifdef SEGV_BNDERR
-		if (from->si_signo == SIGSEGV && from->si_code == SEGV_BNDERR) {
-			err |= __put_user(from->si_lower, &to->si_lower);
-			err |= __put_user(from->si_upper, &to->si_upper);
-		}
-#endif
-#ifdef SEGV_PKUERR
-		if (from->si_signo == SIGSEGV && from->si_code == SEGV_PKUERR)
-			err |= __put_user(from->si_pkey, &to->si_pkey);
-#endif
-		break;
-	case SIL_CHLD:
-		err |= __put_user(from->si_pid, &to->si_pid);
-		err |= __put_user(from->si_uid, &to->si_uid);
-		err |= __put_user(from->si_status, &to->si_status);
-		err |= __put_user(from->si_utime, &to->si_utime);
-		err |= __put_user(from->si_stime, &to->si_stime);
-		break;
-	case SIL_RT:
-		err |= __put_user(from->si_pid, &to->si_pid);
-		err |= __put_user(from->si_uid, &to->si_uid);
-		err |= __put_user(from->si_ptr, &to->si_ptr);
-		break;
-	case SIL_SYS:
-		err |= __put_user(from->si_call_addr, &to->si_call_addr);
-		err |= __put_user(from->si_syscall, &to->si_syscall);
-		err |= __put_user(from->si_arch, &to->si_arch);
-		break;
-	}
-	return err;
+	return 0;
 }
 
 #ifdef CONFIG_COMPAT
-- 
2.14.1

[REVIEW][PATCH 08/17] signal: Stop special casing TRAP_FIXME and FPE_FIXME in siginfo_layout

[Eric W. Biederman]

After more experience with the cases where no one the si_code of 0
is used both as a signal specific si_code, and as SI_USER it appears
that no one cares about the signal specific si_code case and the
good solution is to just fix the architectures by using
a different si_code.

In none of the conversations has anyone even suggested that
anything depends on the signal specific redefinition of SI_USER.

There are at least test cases that care when si_code as 0 does
not work as si_user.

So make things simple and keep the generic code from introducing
problems by removing the special casing of TRAP_FIXME and FPE_FIXME.
This will ensure the generic case of sending a signal with
kill will always set SI_USER and work.

The architecture specific, and signal specific overloads that
set si_code to 0 will now have problems with signalfd and
the 32bit compat versions of siginfo copying.   At least
until they are fixed.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 kernel/signal.c | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/kernel/signal.c b/kernel/signal.c
index d56f4d496c89..fc82d2c0918f 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2835,15 +2835,6 @@ enum siginfo_layout siginfo_layout(int sig, int si_code)
 			layout = SIL_POLL;
 		else if (si_code < 0)
 			layout = SIL_RT;
-		/* Tests to support buggy kernel ABIs */
-#ifdef TRAP_FIXME
-		if ((sig == SIGTRAP) && (si_code == TRAP_FIXME))
-			layout = SIL_FAULT;
-#endif
-#ifdef FPE_FIXME
-		if ((sig == SIGFPE) && (si_code == FPE_FIXME))
-			layout = SIL_FAULT;
-#endif
 	}
 	return layout;
 }
-- 
2.14.1

[REVIEW][PATCH 09/17] signal: Remove SEGV_BNDERR ifdefs

[Eric W. Biederman]

After the last round of cleanups to siginfo.h SEGV_BNDERR is defined
on all architectures so testing to see if it is defined is unnecessary.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 kernel/signal.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/kernel/signal.c b/kernel/signal.c
index fc82d2c0918f..a6d55a6e9915 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1570,7 +1570,6 @@ int send_sig_mceerr(int code, void __user *addr, short lsb, struct task_struct *
 EXPORT_SYMBOL(send_sig_mceerr);
 #endif
 
-#ifdef SEGV_BNDERR
 int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper)
 {
 	struct siginfo info;
@@ -1584,7 +1583,6 @@ int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper)
 	info.si_upper = upper;
 	return force_sig_info(info.si_signo, &info, current);
 }
-#endif
 
 #ifdef SEGV_PKUERR
 int force_sig_pkuerr(void __user *addr, u32 pkey)
@@ -2890,13 +2888,11 @@ int __copy_siginfo_to_user32(struct compat_siginfo __user *to,
 		if ((from->si_signo == SIGBUS) && (from->si_code == BUS_MCEERR_AO))
 			new.si_addr_lsb = from->si_addr_lsb;
 #endif
-#ifdef SEGV_BNDERR
 		if ((from->si_signo == SIGSEGV) &&
 		    (from->si_code == SEGV_BNDERR)) {
 			new.si_lower = ptr_to_compat(from->si_lower);
 			new.si_upper = ptr_to_compat(from->si_upper);
 		}
-#endif
 #ifdef SEGV_PKUERR
 		if ((from->si_signo == SIGSEGV) &&
 		    (from->si_code == SEGV_PKUERR))
@@ -2976,12 +2972,10 @@ int copy_siginfo_from_user32(struct siginfo *to,
 		if ((from.si_signo == SIGBUS) && (from.si_code == BUS_MCEERR_AO))
 			to->si_addr_lsb = from.si_addr_lsb;
 #endif
-#ifdef SEGV_BNDERR
 		if ((from.si_signo == SIGSEGV) && (from.si_code == SEGV_BNDERR)) {
 			to->si_lower = compat_ptr(from.si_lower);
 			to->si_upper = compat_ptr(from.si_upper);
 		}
-#endif
 #ifdef SEGV_PKUERR
 		if ((from.si_signo == SIGSEGV) && (from.si_code == SEGV_PKUERR))
 			to->si_pkey = from.si_pkey;
-- 
2.14.1

[REVIEW][PATCH 10/17] signal: Remove ifdefs for BUS_MCEERR_AR and BUS_MCEERR_AO

[Eric W. Biederman]

With the recent architecture cleanups these si_codes are always
defined so there is no need to test for them.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 fs/signalfd.c   | 15 ++-------------
 kernel/signal.c | 24 ++++++++----------------
 2 files changed, 10 insertions(+), 29 deletions(-)

diff --git a/fs/signalfd.c b/fs/signalfd.c
index d2187a813376..ff302bf50be4 100644
--- a/fs/signalfd.c
+++ b/fs/signalfd.c
@@ -117,26 +117,15 @@ static int signalfd_copyinfo(struct signalfd_siginfo __user *uinfo,
 #ifdef __ARCH_SI_TRAPNO
 		err |= __put_user(kinfo->si_trapno, &uinfo->ssi_trapno);
 #endif
-#ifdef BUS_MCEERR_AO
 		/*
 		 * Other callers might not initialize the si_lsb field,
 		 * so check explicitly for the right codes here.
 		 */
 		if (kinfo->si_signo == SIGBUS &&
-		     kinfo->si_code == BUS_MCEERR_AO)
+		    ((kinfo->si_code == BUS_MCEERR_AR) ||
+		     (kinfo->si_code == BUS_MCEERR_AO)))
 			err |= __put_user((short) kinfo->si_addr_lsb,
 					  &uinfo->ssi_addr_lsb);
-#endif
-#ifdef BUS_MCEERR_AR
-		/*
-		 * Other callers might not initialize the si_lsb field,
-		 * so check explicitly for the right codes here.
-		 */
-		if (kinfo->si_signo == SIGBUS &&
-		    kinfo->si_code == BUS_MCEERR_AR)
-			err |= __put_user((short) kinfo->si_addr_lsb,
-					  &uinfo->ssi_addr_lsb);
-#endif
 		break;
 	case SIL_CHLD:
 		err |= __put_user(kinfo->si_pid, &uinfo->ssi_pid);
diff --git a/kernel/signal.c b/kernel/signal.c
index a6d55a6e9915..b87a9c21f698 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1539,7 +1539,6 @@ int send_sig_fault(int sig, int code, void __user *addr
 	return send_sig_info(info.si_signo, &info, t);
 }
 
-#if defined(BUS_MCEERR_AO) && defined(BUS_MCEERR_AR)
 int force_sig_mceerr(int code, void __user *addr, short lsb, struct task_struct *t)
 {
 	struct siginfo info;
@@ -1568,7 +1567,6 @@ int send_sig_mceerr(int code, void __user *addr, short lsb, struct task_struct *
 	return send_sig_info(info.si_signo, &info, t);
 }
 EXPORT_SYMBOL(send_sig_mceerr);
-#endif
 
 int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper)
 {
@@ -2880,14 +2878,11 @@ int __copy_siginfo_to_user32(struct compat_siginfo __user *to,
 #ifdef __ARCH_SI_TRAPNO
 		new.si_trapno = from->si_trapno;
 #endif
-#ifdef BUS_MCEERR_AR
-		if ((from->si_signo == SIGBUS) && (from->si_code == BUS_MCEERR_AR))
-			new.si_addr_lsb = from->si_addr_lsb;
-#endif
-#ifdef BUS_MCEERR_AO
-		if ((from->si_signo == SIGBUS) && (from->si_code == BUS_MCEERR_AO))
+		if ((from->si_signo == SIGBUS) &&
+		    ((from->si_code == BUS_MCEERR_AR) ||
+		     (from->si_code == BUS_MCEERR_AO)))
 			new.si_addr_lsb = from->si_addr_lsb;
-#endif
+
 		if ((from->si_signo == SIGSEGV) &&
 		    (from->si_code == SEGV_BNDERR)) {
 			new.si_lower = ptr_to_compat(from->si_lower);
@@ -2964,14 +2959,11 @@ int copy_siginfo_from_user32(struct siginfo *to,
 #ifdef __ARCH_SI_TRAPNO
 		to->si_trapno = from.si_trapno;
 #endif
-#ifdef BUS_MCEERR_AR
-		if ((from.si_signo == SIGBUS) && (from.si_code == BUS_MCEERR_AR))
+		if ((from.si_signo == SIGBUS) &&
+		    ((from.si_code == BUS_MCEERR_AR) ||
+		     (from.si_code == BUS_MCEERR_AO)))
 			to->si_addr_lsb = from.si_addr_lsb;
-#endif
-#ifdef BUS_MCEER_AO
-		if ((from.si_signo == SIGBUS) && (from.si_code == BUS_MCEERR_AO))
-			to->si_addr_lsb = from.si_addr_lsb;
-#endif
+
 		if ((from.si_signo == SIGSEGV) && (from.si_code == SEGV_BNDERR)) {
 			to->si_lower = compat_ptr(from.si_lower);
 			to->si_upper = compat_ptr(from.si_upper);
-- 
2.14.1

[REVIEW][PATCH 11/17] signal/alpha: Replace FPE_FIXME with FPE_FLTUNK

[Eric W. Biederman]

Using an si_code of 0 that aliases with SI_USER is clearly the wrong
thing todo, and causes problems in interesting ways.

The newly defined FPE_FLTUNK semantically appears to fit the bill so
use it instead.

Given recent experience in this area odds are it will not break
anything.  Fixing it removes a hazard to kernel maintenance.

Cc: Helge Deller <deller@gmx.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: linux-alpha@vger.kernel.org
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Fixes: 0a635c7a84cf ("Fill in siginfo_t.")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/alpha/include/uapi/asm/siginfo.h | 7 -------
 arch/alpha/kernel/osf_sys.c           | 2 +-
 arch/alpha/kernel/traps.c             | 2 +-
 3 files changed, 2 insertions(+), 9 deletions(-)

diff --git a/arch/alpha/include/uapi/asm/siginfo.h b/arch/alpha/include/uapi/asm/siginfo.h
index 0cf3b527b274..3ebbb1e17902 100644
--- a/arch/alpha/include/uapi/asm/siginfo.h
+++ b/arch/alpha/include/uapi/asm/siginfo.h
@@ -7,13 +7,6 @@
 
 #include <asm-generic/siginfo.h>
 
-/*
- * SIGFPE si_codes
- */
-#ifdef __KERNEL__
-#define FPE_FIXME	0	/* Broken dup of SI_USER */
-#endif /* __KERNEL__ */
-
 /*
  * SIGTRAP si_codes
  */
diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c
index f5f154942aab..bb3619118926 100644
--- a/arch/alpha/kernel/osf_sys.c
+++ b/arch/alpha/kernel/osf_sys.c
@@ -872,7 +872,7 @@ SYSCALL_DEFINE5(osf_setsysinfo, unsigned long, op, void __user *, buffer,
 		fex = (exc >> IEEE_STATUS_TO_EXCSUM_SHIFT) & swcr;
  		if (fex) {
 			siginfo_t info;
-			int si_code = FPE_FIXME;
+			int si_code = FPE_FLTUNK;
 
 			if (fex & IEEE_TRAP_ENABLE_DNO) si_code = FPE_FLTUND;
 			if (fex & IEEE_TRAP_ENABLE_INE) si_code = FPE_FLTRES;
diff --git a/arch/alpha/kernel/traps.c b/arch/alpha/kernel/traps.c
index 91636765dd6d..422b676b28f2 100644
--- a/arch/alpha/kernel/traps.c
+++ b/arch/alpha/kernel/traps.c
@@ -328,7 +328,7 @@ do_entIF(unsigned long type, struct pt_regs *regs)
 			break;
 		case GEN_ROPRAND:
 			signo = SIGFPE;
-			code = FPE_FIXME;
+			code = FPE_FLTUNK;
 			break;
 
 		case GEN_DECOVF:
-- 
2.14.1

[REVIEW][PATCH 12/17] signal/ia64: Replace FPE_FIXME with FPE_FLTUNK

[Eric W. Biederman]

Using an si_code of 0 that aliases with SI_USER is clearly the wrong
thing todo, and causes problems in interesting ways.

The newly defined FPE_FLTUNK semantically appears to fit the bill so
use it instead.

Given recent experience in this area odds are it will not
break anything.  Fixing it removes a hazard to kernel maintenance.

Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
Fixes: 987159266c45 ("Linux version 2.3.48")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/ia64/include/uapi/asm/siginfo.h | 7 -------
 arch/ia64/kernel/traps.c             | 4 ++--
 2 files changed, 2 insertions(+), 9 deletions(-)

diff --git a/arch/ia64/include/uapi/asm/siginfo.h b/arch/ia64/include/uapi/asm/siginfo.h
index 5aa454ed89db..52b5af424511 100644
--- a/arch/ia64/include/uapi/asm/siginfo.h
+++ b/arch/ia64/include/uapi/asm/siginfo.h
@@ -27,11 +27,4 @@
 #define __ISR_VALID_BIT	0
 #define __ISR_VALID	(1 << __ISR_VALID_BIT)
 
-/*
- * SIGFPE si_codes
- */
-#ifdef __KERNEL__
-#define FPE_FIXME	0	/* Broken dup of SI_USER */
-#endif /* __KERNEL__ */
-
 #endif /* _UAPI_ASM_IA64_SIGINFO_H */
diff --git a/arch/ia64/kernel/traps.c b/arch/ia64/kernel/traps.c
index 972873ed1ae5..c6f4932073a1 100644
--- a/arch/ia64/kernel/traps.c
+++ b/arch/ia64/kernel/traps.c
@@ -353,7 +353,7 @@ handle_fpu_swa (int fp_fault, struct pt_regs *regs, unsigned long isr)
 			clear_siginfo(&siginfo);
 			siginfo.si_signo = SIGFPE;
 			siginfo.si_errno = 0;
-			siginfo.si_code = FPE_FIXME;	/* default code */
+			siginfo.si_code = FPE_FLTUNK;	/* default code */
 			siginfo.si_addr = (void __user *) (regs->cr_iip + ia64_psr(regs)->ri);
 			if (isr & 0x11) {
 				siginfo.si_code = FPE_FLTINV;
@@ -380,7 +380,7 @@ handle_fpu_swa (int fp_fault, struct pt_regs *regs, unsigned long isr)
 			clear_siginfo(&siginfo);
 			siginfo.si_signo = SIGFPE;
 			siginfo.si_errno = 0;
-			siginfo.si_code = FPE_FIXME;	/* default code */
+			siginfo.si_code = FPE_FLTUNK;	/* default code */
 			siginfo.si_addr = (void __user *) (regs->cr_iip + ia64_psr(regs)->ri);
 			if (isr & 0x880) {
 				siginfo.si_code = FPE_FLTOVF;
-- 
2.14.1

[REVIEW][PATCH 13/17] signal/powerpc: Replace FPE_FIXME with FPE_FLTUNK

[Eric W. Biederman]

Using an si_code of 0 that aliases with SI_USER is clearly the
wrong thing todo, and causes problems in interesting ways.

The newly defined FPE_FLTUNK semantically appears to fit the
bill so use it instead.

Cc: Paul Mackerras <paulus@samba.org>
Cc: Kumar Gala <kumar.gala@freescale.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc:  linuxppc-dev@lists.ozlabs.org
Fixes: 9bad068c24d7 ("[PATCH] ppc32: support for e500 and 85xx")
Fixes: 0ed70f6105ef ("PPC32: Provide proper siginfo information on various exceptions.")
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/powerpc/include/uapi/asm/siginfo.h | 7 -------
 arch/powerpc/kernel/traps.c             | 6 +++---
 2 files changed, 3 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/include/uapi/asm/siginfo.h b/arch/powerpc/include/uapi/asm/siginfo.h
index 9f142451a01f..0437afc9ef3c 100644
--- a/arch/powerpc/include/uapi/asm/siginfo.h
+++ b/arch/powerpc/include/uapi/asm/siginfo.h
@@ -15,13 +15,6 @@
 
 #include <asm-generic/siginfo.h>
 
-/*
- * SIGFPE si_codes
- */
-#ifdef __KERNEL__
-#define FPE_FIXME	0	/* Broken dup of SI_USER */
-#endif /* __KERNEL__ */
-
 /*
  * SIGTRAP si_codes
  */
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 087855caf6a9..fdf9400beec8 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -1031,7 +1031,7 @@ static void emulate_single_step(struct pt_regs *regs)
 
 static inline int __parse_fpscr(unsigned long fpscr)
 {
-	int ret = FPE_FIXME;
+	int ret = FPE_FLTUNK;
 
 	/* Invalid operation */
 	if ((fpscr & FPSCR_VE) && (fpscr & FPSCR_VX))
@@ -1972,7 +1972,7 @@ void SPEFloatingPointException(struct pt_regs *regs)
 	extern int do_spe_mathemu(struct pt_regs *regs);
 	unsigned long spefscr;
 	int fpexc_mode;
-	int code = FPE_FIXME;
+	int code = FPE_FLTUNK;
 	int err;
 
 	flush_spe_to_thread(current);
@@ -2041,7 +2041,7 @@ void SPEFloatingPointRoundException(struct pt_regs *regs)
 		printk(KERN_ERR "unrecognized spe instruction "
 		       "in %s at %lx\n", current->comm, regs->nip);
 	} else {
-		_exception(SIGFPE, regs, FPE_FIXME, regs->nip);
+		_exception(SIGFPE, regs, FPE_FLTUNK, regs->nip);
 		return;
 	}
 }
-- 
2.14.1

[REVIEW][PATCH 14/17] signal/unicore32: Use FPE_FLTUNK instead of 0 in ucf64_raise_sigfpe

[Eric W. Biederman]

The si_code of 0 (aka SI_USER) has fields si_pid and si_uid not
si_addr so it so only by luck would the appropriate fields by copied
to userspace by copy_siginfo_to_user.

This is just broken and wrong.

Make it obvious what is happening by moving the si_code from a
parameter of the one call to ucf64_raise_sigfpe to a constant value
that info.si_code gets set to.

Explicitly set the si_code to FPE_FLTUNK the newly reserved floating
point si_code for an unknown floating point exception.

It looks like there is a fair chance that this is a code path that has
never been used in real life on unicore32.  The bad si_code and the
print statement that calls it an unhandled exception.  So I really
don't expect anyone will mind if this just gets fixed.

In similar situations on more popular architectures the conclusion was
just fix it.

Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Arnd Bergmann <arnd@arndb.de>
Fixes: d9bc15794d12 ("unicore32 additional architecture files: float point handling")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/unicore32/kernel/fpu-ucf64.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/unicore32/kernel/fpu-ucf64.c b/arch/unicore32/kernel/fpu-ucf64.c
index d785955e1c29..8594b168f25e 100644
--- a/arch/unicore32/kernel/fpu-ucf64.c
+++ b/arch/unicore32/kernel/fpu-ucf64.c
@@ -52,14 +52,14 @@
  * Raise a SIGFPE for the current process.
  * sicode describes the signal being raised.
  */
-void ucf64_raise_sigfpe(unsigned int sicode, struct pt_regs *regs)
+void ucf64_raise_sigfpe(struct pt_regs *regs)
 {
 	siginfo_t info;
 
 	clear_siginfo(&info);
 
 	info.si_signo = SIGFPE;
-	info.si_code = sicode;
+	info.si_code = FPE_FLTUNK;
 	info.si_addr = (void __user *)(instruction_pointer(regs) - 4);
 
 	/*
@@ -94,7 +94,7 @@ void ucf64_exchandler(u32 inst, u32 fpexc, struct pt_regs *regs)
 		pr_debug("UniCore-F64 FPSCR 0x%08x INST 0x%08x\n",
 				cff(FPSCR), inst);
 
-		ucf64_raise_sigfpe(0, regs);
+		ucf64_raise_sigfpe(regs);
 		return;
 	}
 
-- 
2.14.1

[REVIEW][PATCH 15/17] signal: Add TRAP_UNK si_code for undiagnosted trap exceptions

[Eric W. Biederman]

Both powerpc and alpha have cases where they wronly set si_code to 0
in combination with SIGTRAP and don't mean SI_USER.

About half the time this is because the architecture can not report
accurately what kind of trap exception triggered the trap exception.
The other half the time it looks like no one has bothered to
figure out an appropriate si_code.

For the cases where the architecture does not have enough information
or is too lazy to figure out exactly what kind of trap exception
it is define TRAP_UNK.

Cc: linux-api@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-alpha@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/x86/kernel/signal_compat.c    | 2 +-
 include/uapi/asm-generic/siginfo.h | 3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/signal_compat.c b/arch/x86/kernel/signal_compat.c
index 14c057f29979..9ccbf0576cd0 100644
--- a/arch/x86/kernel/signal_compat.c
+++ b/arch/x86/kernel/signal_compat.c
@@ -29,7 +29,7 @@ static inline void signal_compat_build_tests(void)
 	BUILD_BUG_ON(NSIGFPE  != 15);
 	BUILD_BUG_ON(NSIGSEGV != 7);
 	BUILD_BUG_ON(NSIGBUS  != 5);
-	BUILD_BUG_ON(NSIGTRAP != 4);
+	BUILD_BUG_ON(NSIGTRAP != 5);
 	BUILD_BUG_ON(NSIGCHLD != 6);
 	BUILD_BUG_ON(NSIGSYS  != 1);
 
diff --git a/include/uapi/asm-generic/siginfo.h b/include/uapi/asm-generic/siginfo.h
index 558b902f18d4..80e2a7227205 100644
--- a/include/uapi/asm-generic/siginfo.h
+++ b/include/uapi/asm-generic/siginfo.h
@@ -249,7 +249,8 @@ typedef struct siginfo {
 #define TRAP_TRACE	2	/* process trace trap */
 #define TRAP_BRANCH     3	/* process taken branch trap */
 #define TRAP_HWBKPT     4	/* hardware breakpoint/watchpoint */
-#define NSIGTRAP	4
+#define TRAP_UNK	5	/* undiagnosed trap */
+#define NSIGTRAP	5
 
 /*
  * There is an additional set of SIGTRAP si_codes used by ptrace
-- 
2.14.1

[REVIEW][PATCH 16/17] signal/alpha: Replace TRAP_FIXME with TRAP_UNK

[Eric W. Biederman]

Using an si_code of 0 that aliases with SI_USER is clearly the wrong
thing to do, and causes problems in interesting ways.

For it really is not clear to me if using TRAP_UNK bugcheck or
the default case of gentrap is really the best way to handle
things.  There is certainly enough information that that a more
specific si_code could potentially be used.  That said TRAP_UNK
is definitely an improvement over 0 as it removes the ambiguiuty
of what si_code of 0 with SIGTRAP means on alpha.

Recent history suggests no actually cares about crazy corner cases of
the kernel behavior like this so I don't expect any regressions from
changing this.  However if something does happen this change is easy
to revert.

Cc: Helge Deller <deller@gmx.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: linux-alpha@vger.kernel.org
Fixes: 0a635c7a84cf ("Fill in siginfo_t.")
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/alpha/include/uapi/asm/siginfo.h | 7 -------
 arch/alpha/kernel/traps.c             | 4 ++--
 2 files changed, 2 insertions(+), 9 deletions(-)

diff --git a/arch/alpha/include/uapi/asm/siginfo.h b/arch/alpha/include/uapi/asm/siginfo.h
index 3ebbb1e17902..db3f0138536f 100644
--- a/arch/alpha/include/uapi/asm/siginfo.h
+++ b/arch/alpha/include/uapi/asm/siginfo.h
@@ -7,11 +7,4 @@
 
 #include <asm-generic/siginfo.h>
 
-/*
- * SIGTRAP si_codes
- */
-#ifdef __KERNEL__
-#define TRAP_FIXME	0	/* Broken dup of SI_USER */
-#endif /* __KERNEL__ */
-
 #endif
diff --git a/arch/alpha/kernel/traps.c b/arch/alpha/kernel/traps.c
index 422b676b28f2..242c83d86ace 100644
--- a/arch/alpha/kernel/traps.c
+++ b/arch/alpha/kernel/traps.c
@@ -288,7 +288,7 @@ do_entIF(unsigned long type, struct pt_regs *regs)
 	      case 1: /* bugcheck */
 		info.si_signo = SIGTRAP;
 		info.si_errno = 0;
-		info.si_code = TRAP_FIXME;
+		info.si_code = TRAP_UNK;
 		info.si_addr = (void __user *) regs->pc;
 		info.si_trapno = 0;
 		send_sig_info(SIGTRAP, &info, current);
@@ -350,7 +350,7 @@ do_entIF(unsigned long type, struct pt_regs *regs)
 		case GEN_SUBRNG7:
 		default:
 			signo = SIGTRAP;
-			code = TRAP_FIXME;
+			code = TRAP_UNK;
 			break;
 		}
 
-- 
2.14.1

[REVIEW][PATCH 17/17] signal/powerpc: Replace TRAP_FIXME with TRAP_UNK

[Eric W. Biederman]

Using an si_code of 0 that aliases with SI_USER is clearly the wrong
thing todo, and causes problems in interesting ways.

For use in unknown_exception the recently defined TRAP_UNK
semantically is a perfect fit.  For use in RunModeException it looks
like something more specific than TRAP_UNK could be used.  No one has
bothered to find a better fit than the broken si_code of 0 in all of
these years and I don't see an obvious better fit so TRAP_UNK is
switching RunModeException to return TRAP_UNK is clearly an
improvement.

Recent history suggests no actually cares about crazy corner
cases of the kernel behavior like this so I don't expect any
regressions from changing this.  However if something does
happen this change is easy to revert.

Though I wonder if SIGKILL might not be a better fit.

Cc: Paul Mackerras <paulus@samba.org>
Cc: Kumar Gala <kumar.gala@freescale.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linuxppc-dev@lists.ozlabs.org
Fixes: 9bad068c24d7 ("[PATCH] ppc32: support for e500 and 85xx")
Fixes: 0ed70f6105ef ("PPC32: Provide proper siginfo information on various exceptions.")
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/powerpc/include/uapi/asm/siginfo.h | 8 --------
 arch/powerpc/kernel/traps.c             | 4 ++--
 2 files changed, 2 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/include/uapi/asm/siginfo.h b/arch/powerpc/include/uapi/asm/siginfo.h
index 0437afc9ef3c..1d51d9b88221 100644
--- a/arch/powerpc/include/uapi/asm/siginfo.h
+++ b/arch/powerpc/include/uapi/asm/siginfo.h
@@ -15,12 +15,4 @@
 
 #include <asm-generic/siginfo.h>
 
-/*
- * SIGTRAP si_codes
- */
-#ifdef __KERNEL__
-#define TRAP_FIXME	0	/* Broken dup of SI_USER */
-#endif /* __KERNEL__ */
-
-
 #endif	/* _ASM_POWERPC_SIGINFO_H */
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index fdf9400beec8..0e17dcb48720 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -969,7 +969,7 @@ void unknown_exception(struct pt_regs *regs)
 	printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
 	       regs->nip, regs->msr, regs->trap);
 
-	_exception(SIGTRAP, regs, TRAP_FIXME, 0);
+	_exception(SIGTRAP, regs, TRAP_UNK, 0);
 
 	exception_exit(prev_state);
 }
@@ -991,7 +991,7 @@ void instruction_breakpoint_exception(struct pt_regs *regs)
 
 void RunModeException(struct pt_regs *regs)
 {
-	_exception(SIGTRAP, regs, TRAP_FIXME, 0);
+	_exception(SIGTRAP, regs, TRAP_UNK, 0);
 }
 
 void single_step_exception(struct pt_regs *regs)
-- 
2.14.1

Re: [REVIEW][PATCH 05/17] signal/nds32: Use force_sig(SIGILL) in do_revisn

[Vincent Chen]

2018-04-20 9:03 GMT+08:00 Eric W. Biederman <ebiederm@xmission.com>:
> As originally committed do_revisn would deliver a siginfo for SIGILL
> with an si_code composed of random stack contents.  That makes no
> sense and is not something userspace can depend on.  So simplify
> the code and just use "force_sig(SIG_ILL, current)" instead.
>
> Fixes: 2923f5ea7738 ("nds32: Exception handling")
> Cc: Vincent Chen <vincentc@andestech.com>
> Cc: Greentime Hu <greentime@andestech.com>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
> ---
>  arch/nds32/kernel/traps.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c
> index 65961bf91d64..8e9a5b1f6234 100644
> --- a/arch/nds32/kernel/traps.c
> +++ b/arch/nds32/kernel/traps.c
> @@ -356,14 +356,11 @@ void do_dispatch_tlb_misc(unsigned long entry, unsigned long addr,
>
>  void do_revinsn(struct pt_regs *regs)
>  {
> -       siginfo_t si;
>         pr_emerg("Reserved Instruction\n");
>         show_regs(regs);
>         if (!user_mode(regs))
>                 do_exit(SIGILL);
> -       si.si_signo = SIGILL;
> -       si.si_errno = 0;
> -       force_sig_info(SIGILL, &si, current);
> +       force_sig(SIGILL, current);
>  }
>
>  #ifdef CONFIG_ALIGNMENT_TRAP
> --
> 2.14.1
>

You are right we do not store any valuable information in sigingo_t now.
However, We hope more information can be recorded by force_sig_fault()
as below instead of calling force_sig() directly.

-        force_sig(SIGILL, current);
+        force_sig_fault(SIGILL, ILL_ILLTRP,
+                        (void __user *)instruction_pointer(regs), current);

Thanks

Vincent Chen

Re: [REVIEW][PATCH 04/17] signal/nds32: Use force_sig in unhandled_interruption and unhandled_exceptions

[Vincent Chen]

2018-04-20 9:03 GMT+08:00 Eric W. Biederman <ebiederm@xmission.com>:
> Neither unhandled_interrupt nor unhandled_exceptions fills in any of the
> siginfo fields whend sending SIGKILL.  Further because it is SIGKILL
> even if all of the fields were filled out appropriately it would be impossible
> for the process to read any of the siginfo fields.  So simplfy things and
> just use force_sig instead of force_sig_info.
>
> Fixes: 2923f5ea7738 ("nds32: Exception handling")
> Cc: Vincent Chen <vincentc@andestech.com>
> Cc: Greentime Hu <greentime@andestech.com>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
> ---
>  arch/nds32/kernel/traps.c | 11 ++---------
>  1 file changed, 2 insertions(+), 9 deletions(-)
>
> diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c
> index 6e34eb9824a4..65961bf91d64 100644
> --- a/arch/nds32/kernel/traps.c
> +++ b/arch/nds32/kernel/traps.c
> @@ -318,29 +318,22 @@ void do_debug_trap(unsigned long entry, unsigned long addr,
>
>  void unhandled_interruption(struct pt_regs *regs)
>  {
> -       siginfo_t si;
>         pr_emerg("unhandled_interruption\n");
>         show_regs(regs);
>         if (!user_mode(regs))
>                 do_exit(SIGKILL);
> -       si.si_signo = SIGKILL;
> -       si.si_errno = 0;
> -       force_sig_info(SIGKILL, &si, current);
> +       force_sig(SIGKILL, current);
>  }
>
>  void unhandled_exceptions(unsigned long entry, unsigned long addr,
>                           unsigned long type, struct pt_regs *regs)
>  {
> -       siginfo_t si;
>         pr_emerg("Unhandled Exception: entry: %lx addr:%lx itype:%lx\n", entry,
>                  addr, type);
>         show_regs(regs);
>         if (!user_mode(regs))
>                 do_exit(SIGKILL);
> -       si.si_signo = SIGKILL;
> -       si.si_errno = 0;
> -       si.si_addr = (void *)addr;
> -       force_sig_info(SIGKILL, &si, current);
> +       force_sig(SIGKILL, current);
>  }
>
>  extern int do_page_fault(unsigned long entry, unsigned long addr,
> --
> 2.14.1
>

Acked-by Vincent Chen

[PATCH] signal/nds32: More information in do_revinsn

[Eric W. Biederman]

While reviewing f6ed1ecad56f ("signal/nds32: Use force_sig(SIGILL) in do_revisn")
Vincent Chen asked if it was possible to provide more information in do_revinsn
with force_sig_fault.

That seems reasonable and the appropirate si_code appears to be
ILL_ILLOPC (illegal opcode) as the printk indicates this code path
is triggered when a reserved instruction is exectured.

So update do_revinsn to use force_sig_fault(SIGILL, ILL_ILLOPC, ...).
Giving userspace a much better experience when soemone attempts
to execute a reserved instruction.

Cc: Greentime Hu <green.hu@gmail.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Suggested-by: Vincent Chen <deanbo422@gmail.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---

Vincent I have updated this from your suggestion to use
ILL_ILLOPC as that appears the more appropriate si_code.
Normally I expect you could just update your nds32 tree and
make this kind of change but since I am touching this code anyway I will
be happy to take this change along with the others.

Does this look good to you?

 arch/nds32/kernel/traps.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c
index a6205fd4db52..5c2f61835ab9 100644
--- a/arch/nds32/kernel/traps.c
+++ b/arch/nds32/kernel/traps.c
@@ -349,7 +349,8 @@ void do_revinsn(struct pt_regs *regs)
 	show_regs(regs);
 	if (!user_mode(regs))
 		do_exit(SIGILL);
-	force_sig(SIGILL, current);
+	force_sig_fault(SIGILL, ILL_ILLOPC,
+			(void __user *)instruction_pointer(regs), current);
 }
 
 #ifdef CONFIG_ALIGNMENT_TRAP
-- 
2.14.1

Re: [PATCH] signal/nds32: More information in do_revinsn

[Vincent Chen]

2018-04-26 0:13 GMT+08:00 Eric W. Biederman <ebiederm@xmission.com>:
>
> While reviewing f6ed1ecad56f ("signal/nds32: Use force_sig(SIGILL) in do_revisn")
> Vincent Chen asked if it was possible to provide more information in do_revinsn
> with force_sig_fault.
>
> That seems reasonable and the appropirate si_code appears to be
> ILL_ILLOPC (illegal opcode) as the printk indicates this code path
> is triggered when a reserved instruction is exectured.
>

I think error code is set as ILL_ILLOPC is a good choice for normal
reserved instruction
but it seems a little bit inappropriate for nds32. For nds32 reserved
exception, It is possibly
triggered by illegal opcode, operand and immediate. Unfortunately,
do_revisn() can not
identify the actual reason now. Therefore, I chose ILLTRAP to avoid
confusing user when
the reserved exception is cauesd by wrong immediate or operand.



> So update do_revinsn to use force_sig_fault(SIGILL, ILL_ILLOPC, ...).
> Giving userspace a much better experience when soemone attempts
> to execute a reserved instruction.
>
> Cc: Greentime Hu <green.hu@gmail.com>
> Cc: Vincent Chen <deanbo422@gmail.com>
> Suggested-by: Vincent Chen <deanbo422@gmail.com>
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
> ---
>
> Vincent I have updated this from your suggestion to use
> ILL_ILLOPC as that appears the more appropriate si_code.
> Normally I expect you could just update your nds32 tree and
> make this kind of change but since I am touching this code anyway I will
> be happy to take this change along with the others.
>
> Does this look good to you?
>

It is fine to commit this change along with the others.

Vincent Chen


>  arch/nds32/kernel/traps.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c
> index a6205fd4db52..5c2f61835ab9 100644
> --- a/arch/nds32/kernel/traps.c
> +++ b/arch/nds32/kernel/traps.c
> @@ -349,7 +349,8 @@ void do_revinsn(struct pt_regs *regs)
>         show_regs(regs);
>         if (!user_mode(regs))
>                 do_exit(SIGILL);
> -       force_sig(SIGILL, current);
> +       force_sig_fault(SIGILL, ILL_ILLOPC,
> +                       (void __user *)instruction_pointer(regs), current);
>  }
>
>  #ifdef CONFIG_ALIGNMENT_TRAP
> --
> 2.14.1
>