[REVIEW][PATCH 0/4] signal/arm: siginfo cleanups

[REVIEW][PATCH 0/4] signal/arm: siginfo cleanups

[Eric W. Biederman]

This is the latest and hopefully round of siginfo cleanups for arm.
This replaces the use of siginal sending functions that take siginfo
with siginfo sending functions that take the values that go in siginfo
and this is harder to get wrong, and frequently results in cleaner code.

I don't think I have made made any mistakes in this coversion but if
people can look the code over and see if they can spot anything I would
appreciate it.

Eric W. Biederman (4):
      signal/arm: Push siginfo generation into arm_notify_die
      signal/arm: Use force_sig_fault where appropriate
      signal/arm: Use send_sig_fault where appropriate
      signal/arm/kvm: Use send_sig_mceerr

 arch/arm/include/asm/bug.h    |  4 +--
 arch/arm/kernel/ptrace.c      | 11 ++------
 arch/arm/kernel/swp_emulate.c | 16 +++++------
 arch/arm/kernel/traps.c       | 63 ++++++++++++-------------------------------
 arch/arm/mm/alignment.c       | 10 +------
 arch/arm/mm/fault.c           | 28 ++++---------------
 arch/arm/vfp/vfpmodule.c      | 11 +++-----
 virt/kvm/arm/mmu.c            | 14 +++-------
 8 files changed, 41 insertions(+), 116 deletions(-)

Eric

[REVIEW][PATCH 1/4] signal/arm: Push siginfo generation into arm_notify_die

[Eric W. Biederman]

In arm_notify_die call force_sig_fault to let the generic
code handle siginfo generation.

This removes some boiler plate making the code easier to
maintain in the long run.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/arm/include/asm/bug.h    |  4 +--
 arch/arm/kernel/swp_emulate.c | 16 ++++-----
 arch/arm/kernel/traps.c       | 63 ++++++++++-------------------------
 arch/arm/mm/fault.c           | 18 +++-------
 4 files changed, 30 insertions(+), 71 deletions(-)

diff --git a/arch/arm/include/asm/bug.h b/arch/arm/include/asm/bug.h
index 237aa52d8733..36c951dd23b8 100644
--- a/arch/arm/include/asm/bug.h
+++ b/arch/arm/include/asm/bug.h
@@ -62,8 +62,8 @@ do {								\
 struct pt_regs;
 void die(const char *msg, struct pt_regs *regs, int err);
 
-struct siginfo;
-void arm_notify_die(const char *str, struct pt_regs *regs, struct siginfo *info,
+void arm_notify_die(const char *str, struct pt_regs *regs,
+		int signo, int si_code, void __user *addr,
 		unsigned long err, unsigned long trap);
 
 #ifdef CONFIG_ARM_LPAE
diff --git a/arch/arm/kernel/swp_emulate.c b/arch/arm/kernel/swp_emulate.c
index 80517f293eb9..a188d5e8ab7f 100644
--- a/arch/arm/kernel/swp_emulate.c
+++ b/arch/arm/kernel/swp_emulate.c
@@ -98,22 +98,20 @@ static int proc_status_show(struct seq_file *m, void *v)
  */
 static void set_segfault(struct pt_regs *regs, unsigned long addr)
 {
-	siginfo_t info;
+	int si_code;
 
-	clear_siginfo(&info);
 	down_read(&current->mm->mmap_sem);
 	if (find_vma(current->mm, addr) == NULL)
-		info.si_code = SEGV_MAPERR;
+		si_code = SEGV_MAPERR;
 	else
-		info.si_code = SEGV_ACCERR;
+		si_code = SEGV_ACCERR;
 	up_read(&current->mm->mmap_sem);
 
-	info.si_signo = SIGSEGV;
-	info.si_errno = 0;
-	info.si_addr  = (void *) instruction_pointer(regs);
-
 	pr_debug("SWP{B} emulation: access caused memory abort!\n");
-	arm_notify_die("Illegal memory access", regs, &info, 0, 0);
+	arm_notify_die("Illegal memory access", regs,
+		       SIGSEGV, si_code,
+		       (void __user *)instruction_pointer(regs),
+		       0, 0);
 
 	abtcounter++;
 }
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
index badf02ca3693..2d668cff8ef4 100644
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -365,13 +365,14 @@ void die(const char *str, struct pt_regs *regs, int err)
 }
 
 void arm_notify_die(const char *str, struct pt_regs *regs,
-		struct siginfo *info, unsigned long err, unsigned long trap)
+		int signo, int si_code, void __user *addr,
+		unsigned long err, unsigned long trap)
 {
 	if (user_mode(regs)) {
 		current->thread.error_code = err;
 		current->thread.trap_no = trap;
 
-		force_sig_info(info->si_signo, info, current);
+		force_sig_fault(signo, si_code, addr, current);
 	} else {
 		die(str, regs, err);
 	}
@@ -438,10 +439,8 @@ int call_undef_hook(struct pt_regs *regs, unsigned int instr)
 asmlinkage void do_undefinstr(struct pt_regs *regs)
 {
 	unsigned int instr;
-	siginfo_t info;
 	void __user *pc;
 
-	clear_siginfo(&info);
 	pc = (void __user *)instruction_pointer(regs);
 
 	if (processor_mode(regs) == SVC_MODE) {
@@ -485,13 +484,8 @@ asmlinkage void do_undefinstr(struct pt_regs *regs)
 		dump_instr(KERN_INFO, regs);
 	}
 #endif
-
-	info.si_signo = SIGILL;
-	info.si_errno = 0;
-	info.si_code  = ILL_ILLOPC;
-	info.si_addr  = pc;
-
-	arm_notify_die("Oops - undefined instruction", regs, &info, 0, 6);
+	arm_notify_die("Oops - undefined instruction", regs,
+		       SIGILL, ILL_ILLOPC, pc, 0, 6);
 }
 NOKPROBE_SYMBOL(do_undefinstr)
 
@@ -539,9 +533,6 @@ asmlinkage void bad_mode(struct pt_regs *regs, int reason)
 
 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;
@@ -555,13 +546,10 @@ static int bad_syscall(int n, struct pt_regs *regs)
 	}
 #endif
 
-	info.si_signo = SIGILL;
-	info.si_errno = 0;
-	info.si_code  = ILL_ILLTRP;
-	info.si_addr  = (void __user *)instruction_pointer(regs) -
-			 (thumb_mode(regs) ? 2 : 4);
-
-	arm_notify_die("Oops - bad syscall", regs, &info, n, 0);
+	arm_notify_die("Oops - bad syscall", regs, SIGILL, ILL_ILLTRP,
+		       (void __user *)instruction_pointer(regs) -
+			 (thumb_mode(regs) ? 2 : 4),
+		       n, 0);
 
 	return regs->ARM_r0;
 }
@@ -607,20 +595,13 @@ do_cache_op(unsigned long start, unsigned long end, int flags)
 #define NR(x) ((__ARM_NR_##x) - __ARM_NR_BASE)
 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);
 
 	switch (no & 0xffff) {
 	case 0: /* branch through 0 */
-		info.si_signo = SIGSEGV;
-		info.si_errno = 0;
-		info.si_code  = SEGV_MAPERR;
-		info.si_addr  = NULL;
-
-		arm_notify_die("branch through zero", regs, &info, 0, 0);
+		arm_notify_die("branch through zero", regs,
+			       SIGSEGV, SEGV_MAPERR, NULL, 0, 0);
 		return 0;
 
 	case NR(breakpoint): /* SWI BREAK_POINT */
@@ -688,13 +669,10 @@ asmlinkage int arm_syscall(int no, struct pt_regs *regs)
 		}
 	}
 #endif
-	info.si_signo = SIGILL;
-	info.si_errno = 0;
-	info.si_code  = ILL_ILLTRP;
-	info.si_addr  = (void __user *)instruction_pointer(regs) -
-			 (thumb_mode(regs) ? 2 : 4);
-
-	arm_notify_die("Oops - bad syscall(2)", regs, &info, no, 0);
+	arm_notify_die("Oops - bad syscall(2)", regs, SIGILL, ILL_ILLTRP,
+		       (void __user *)instruction_pointer(regs) -
+			 (thumb_mode(regs) ? 2 : 4),
+		       no, 0);
 	return 0;
 }
 
@@ -744,9 +722,6 @@ asmlinkage void
 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) {
@@ -757,12 +732,8 @@ baddataabort(int code, unsigned long instr, struct pt_regs *regs)
 	}
 #endif
 
-	info.si_signo = SIGILL;
-	info.si_errno = 0;
-	info.si_code  = ILL_ILLOPC;
-	info.si_addr  = (void __user *)addr;
-
-	arm_notify_die("unknown data abort code", regs, &info, instr, 0);
+	arm_notify_die("unknown data abort code", regs,
+		       SIGILL, ILL_ILLOPC, (void __user *)addr, instr, 0);
 }
 
 void __readwrite_bug(const char *fn)
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 3232afb6fdc0..544d2c8c2775 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -554,7 +554,6 @@ asmlinkage void
 do_DataAbort(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 {
 	const struct fsr_info *inf = fsr_info + fsr_fs(fsr);
-	struct siginfo info;
 
 	if (!inf->fn(addr, fsr & ~FSR_LNX_PF, regs))
 		return;
@@ -563,12 +562,8 @@ 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;
-	info.si_addr  = (void __user *)addr;
-	arm_notify_die("", regs, &info, fsr, 0);
+	arm_notify_die("", regs, inf->sig, inf->code, (void __user *)addr,
+		       fsr, 0);
 }
 
 void __init
@@ -588,7 +583,6 @@ asmlinkage void
 do_PrefetchAbort(unsigned long addr, unsigned int ifsr, struct pt_regs *regs)
 {
 	const struct fsr_info *inf = ifsr_info + fsr_fs(ifsr);
-	struct siginfo info;
 
 	if (!inf->fn(addr, ifsr | FSR_LNX_PF, regs))
 		return;
@@ -596,12 +590,8 @@ 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;
-	info.si_addr  = (void __user *)addr;
-	arm_notify_die("", regs, &info, ifsr, 0);
+	arm_notify_die("", regs, inf->sig, inf->code, (void __user *)addr,
+		       ifsr, 0);
 }
 
 /*
-- 
2.17.1

[REVIEW][PATCH 2/4] signal/arm: Use force_sig_fault where appropriate

[Eric W. Biederman]

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/arm/kernel/ptrace.c | 11 ++---------
 arch/arm/mm/alignment.c  | 10 +---------
 arch/arm/mm/fault.c      | 10 +---------
 3 files changed, 4 insertions(+), 27 deletions(-)

diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index 36718a424358..6fa5b6387556 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -203,15 +203,8 @@ void ptrace_disable(struct task_struct *child)
  */
 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;
-	info.si_addr  = (void __user *)instruction_pointer(regs);
-
-	force_sig_info(SIGTRAP, &info, tsk);
+	force_sig_fault(SIGTRAP, TRAP_BRKPT,
+			(void __user *)instruction_pointer(regs), tsk);
 }
 
 static int break_trap(struct pt_regs *regs, unsigned int instr)
diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c
index bd2c739d8083..b54f8f8def36 100644
--- a/arch/arm/mm/alignment.c
+++ b/arch/arm/mm/alignment.c
@@ -948,15 +948,7 @@ do_alignment(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
 		goto fixup;
 
 	if (ai_usermode & UM_SIGNAL) {
-		siginfo_t si;
-
-		clear_siginfo(&si);
-		si.si_signo = SIGBUS;
-		si.si_errno = 0;
-		si.si_code = BUS_ADRALN;
-		si.si_addr = (void __user *)addr;
-
-		force_sig_info(si.si_signo, &si, current);
+		force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *)addr, current);
 	} else {
 		/*
 		 * We're about to disable the alignment trap and return to
diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index 544d2c8c2775..f4ea4c62c613 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -161,13 +161,9 @@ __do_user_fault(struct task_struct *tsk, unsigned long addr,
 		unsigned int fsr, unsigned int sig, int code,
 		struct pt_regs *regs)
 {
-	struct siginfo si;
-
 	if (addr > TASK_SIZE)
 		harden_branch_predictor();
 
-	clear_siginfo(&si);
-
 #ifdef CONFIG_DEBUG_USER
 	if (((user_debug & UDBG_SEGV) && (sig == SIGSEGV)) ||
 	    ((user_debug & UDBG_BUS)  && (sig == SIGBUS))) {
@@ -181,11 +177,7 @@ __do_user_fault(struct task_struct *tsk, unsigned long addr,
 	tsk->thread.address = addr;
 	tsk->thread.error_code = fsr;
 	tsk->thread.trap_no = 14;
-	si.si_signo = sig;
-	si.si_errno = 0;
-	si.si_code = code;
-	si.si_addr = (void __user *)addr;
-	force_sig_info(sig, &si, tsk);
+	force_sig_fault(sig, code, (void __user *)addr, tsk);
 }
 
 void do_bad_area(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
-- 
2.17.1

[REVIEW][PATCH 3/4] signal/arm: Use send_sig_fault where appropriate

[Eric W. Biederman]

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/arm/vfp/vfpmodule.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c
index dc7e6b50ef67..aa96cc5c9fe9 100644
--- a/arch/arm/vfp/vfpmodule.c
+++ b/arch/arm/vfp/vfpmodule.c
@@ -216,13 +216,6 @@ static struct notifier_block vfp_notifier_block = {
  */
 static void vfp_raise_sigfpe(unsigned int sicode, struct pt_regs *regs)
 {
-	siginfo_t info;
-
-	clear_siginfo(&info);
-	info.si_signo = SIGFPE;
-	info.si_code = sicode;
-	info.si_addr = (void __user *)(instruction_pointer(regs) - 4);
-
 	/*
 	 * This is the same as NWFPE, because it's not clear what
 	 * this is used for
@@ -230,7 +223,9 @@ static void vfp_raise_sigfpe(unsigned int sicode, struct pt_regs *regs)
 	current->thread.error_code = 0;
 	current->thread.trap_no = 6;
 
-	send_sig_info(SIGFPE, &info, current);
+	send_sig_fault(SIGFPE, sicode,
+		       (void __user *)(instruction_pointer(regs) - 4),
+		       current);
 }
 
 static void vfp_panic(char *reason, u32 inst)
-- 
2.17.1

[REVIEW][PATCH 4/4] signal/arm/kvm: Use send_sig_mceerr

[Eric W. Biederman]

This simplifies the code making it clearer what is going on, and
making the siginfo generation easier to maintain.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 virt/kvm/arm/mmu.c | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index 91aaf73b00df..39c0405f2021 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -1450,20 +1450,14 @@ static void invalidate_icache_guest_page(kvm_pfn_t pfn, unsigned long size)
 static void kvm_send_hwpoison_signal(unsigned long address,
 				     struct vm_area_struct *vma)
 {
-	siginfo_t info;
-
-	clear_siginfo(&info);
-	info.si_signo   = SIGBUS;
-	info.si_errno   = 0;
-	info.si_code    = BUS_MCEERR_AR;
-	info.si_addr    = (void __user *)address;
+	short lsb;
 
 	if (is_vm_hugetlb_page(vma))
-		info.si_addr_lsb = huge_page_shift(hstate_vma(vma));
+		lsb = huge_page_shift(hstate_vma(vma));
 	else
-		info.si_addr_lsb = PAGE_SHIFT;
+		lsb = PAGE_SHIFT;
 
-	send_sig_info(SIGBUS, &info, current);
+	send_sig_mceerr(BUS_MCEERR_AR, (void __user *)address, lsb, current);
 }
 
 static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
-- 
2.17.1

[REVIEW][PATCH 1/3] signal/ia64: Use the generic force_sigsegv in setup_frame

[Eric W. Biederman]

The ia64 handling of failure to setup a signal frame has been trying
to set overlapping fields in struct siginfo since 2.3.43.  The si_pid
and si_uid fields are stomped when the si_addr field is set.  The
si_code of SI_KERNEL indicates that si_pid and si_uid should be valid,
and that si_addr does not exist.

Being at odds with the definition of SI_KERNEL and with nothing to
indicate that this was a signal frame setup failure there is no way
for userspace to know that si_addr was filled out instead.

In practice failure to setup a signal frame is rare, and si_pid and
si_uid are always set to 0 when si_code is SI_KERNEL so I expect no
one has looked closely enough before to see this weirdness.  Further
the only difference between force_sigsegv_info and the generic
force_sigsegv other than the return code is that force_sigsegv_info
stomps the si_uid and si_pid fields.

Remove the bug and simplify the code by using force_sigsegv in this
case just like other architectures.

Fixes: 2.3.43
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/ia64/kernel/signal.c | 50 ++++++++++-----------------------------
 1 file changed, 12 insertions(+), 38 deletions(-)

diff --git a/arch/ia64/kernel/signal.c b/arch/ia64/kernel/signal.c
index d1234a5ba4c5..01fc133b2e4c 100644
--- a/arch/ia64/kernel/signal.c
+++ b/arch/ia64/kernel/signal.c
@@ -231,37 +231,6 @@ rbs_on_sig_stack (unsigned long bsp)
 	return (bsp - current->sas_ss_sp < current->sas_ss_size);
 }
 
-static long
-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
-		 * certainly overkill, but this isn't a
-		 * performance-critical path and I'd rather play it safe
-		 * here than having to debug a nasty race if and when
-		 * something changes in kernel/signal.c that would make it
-		 * no longer safe to modify sa_handler without holding the
-		 * lock.
-		 */
-		spin_lock_irqsave(&current->sighand->siglock, flags);
-		current->sighand->action[sig - 1].sa.sa_handler = SIG_DFL;
-		spin_unlock_irqrestore(&current->sighand->siglock, flags);
-	}
-	si.si_signo = SIGSEGV;
-	si.si_errno = 0;
-	si.si_code = SI_KERNEL;
-	si.si_pid = task_pid_vnr(current);
-	si.si_uid = from_kuid_munged(current_user_ns(), current_uid());
-	si.si_addr = addr;
-	force_sig_info(SIGSEGV, &si, current);
-	return 1;
-}
-
 static long
 setup_frame(struct ksignal *ksig, sigset_t *set, struct sigscratch *scr)
 {
@@ -295,15 +264,18 @@ setup_frame(struct ksignal *ksig, sigset_t *set, struct sigscratch *scr)
 			 * instead so we will die with SIGSEGV.
 			 */
 			check_sp = (new_sp - sizeof(*frame)) & -STACK_ALIGN;
-			if (!likely(on_sig_stack(check_sp)))
-				return force_sigsegv_info(ksig->sig, (void __user *)
-							  check_sp);
+			if (!likely(on_sig_stack(check_sp))) {
+				force_sigsegv(ksig->sig, current);
+				return 1;
+			}
 		}
 	}
 	frame = (void __user *) ((new_sp - sizeof(*frame)) & -STACK_ALIGN);
 
-	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
-		return force_sigsegv_info(ksig->sig, frame);
+	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) {
+		force_sigsegv(ksig->sig, current);
+		return 1;
+	}
 
 	err  = __put_user(ksig->sig, &frame->arg0);
 	err |= __put_user(&frame->info, &frame->arg1);
@@ -317,8 +289,10 @@ setup_frame(struct ksignal *ksig, sigset_t *set, struct sigscratch *scr)
 	err |= __save_altstack(&frame->sc.sc_stack, scr->pt.r12);
 	err |= setup_sigcontext(&frame->sc, set, scr);
 
-	if (unlikely(err))
-		return force_sigsegv_info(ksig->sig, frame);
+	if (unlikely(err)) {
+		force_sigsegv(ksig->sig, current);
+		return 1;
+	}
 
 	scr->pt.r12 = (unsigned long) frame - 16;	/* new stack pointer */
 	scr->pt.ar_fpsr = FPSR_DEFAULT;			/* reset fpsr for signal handler */
-- 
2.17.1

[REVIEW][PATCH 2/3] signal/ia64: Use the force_sig(SIGSEGV,...) in ia64_rt_sigreturn

[Eric W. Biederman]

The ia64 handling of failure to return from a signal frame has been trying
to set overlapping fields in struct siginfo since 2.3.43.  The si_code
corresponds to the fields that were stomped (not the field that is
actually written), so I can not imagine a piece of userspace code
making sense of the signal frame if it looks closely.

In practice failure to return from a signal frame is a rare event that
almost never happens.  Someone using an alternate signal stack to
recover and looking in detail is even more rare.  So I presume no one
has ever noticed and reported this ia64 nonsense.

Sort this out by causing ia64 to use force_sig(SIGSEGV) like other architectures.

Fixes: 2.3.43
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/ia64/kernel/signal.c | 10 +---------
 1 file changed, 1 insertion(+), 9 deletions(-)

diff --git a/arch/ia64/kernel/signal.c b/arch/ia64/kernel/signal.c
index 01fc133b2e4c..9a960829a01d 100644
--- a/arch/ia64/kernel/signal.c
+++ b/arch/ia64/kernel/signal.c
@@ -110,7 +110,6 @@ ia64_rt_sigreturn (struct sigscratch *scr)
 {
 	extern char ia64_strace_leave_kernel, ia64_leave_kernel;
 	struct sigcontext __user *sc;
-	struct siginfo si;
 	sigset_t set;
 	long retval;
 
@@ -153,14 +152,7 @@ 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;
-	si.si_pid = task_pid_vnr(current);
-	si.si_uid = from_kuid_munged(current_user_ns(), current_uid());
-	si.si_addr = sc;
-	force_sig_info(SIGSEGV, &si, current);
+	force_sig(SIGSEGV, current);
 	return retval;
 }
 
-- 
2.17.1

[REVIEW][PATCH 3/3] signal/ia64: Use force_sig_fault where appropriate

[Eric W. Biederman]

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/ia64/kernel/brl_emu.c   |  31 ++------
 arch/ia64/kernel/traps.c     | 144 ++++++++++-------------------------
 arch/ia64/kernel/unaligned.c |  12 +--
 arch/ia64/mm/fault.c         |  12 +--
 4 files changed, 49 insertions(+), 150 deletions(-)

diff --git a/arch/ia64/kernel/brl_emu.c b/arch/ia64/kernel/brl_emu.c
index a61f6c6a36f8..c0239bf77a09 100644
--- a/arch/ia64/kernel/brl_emu.c
+++ b/arch/ia64/kernel/brl_emu.c
@@ -58,11 +58,9 @@ ia64_emulate_brl (struct pt_regs *regs, unsigned long ar_ec)
 	unsigned long bundle[2];
 	unsigned long opcode, btype, qp, offset, cpl;
 	unsigned long next_ip;
-	struct siginfo siginfo;
 	struct illegal_op_return rv;
 	long tmp_taken, unimplemented_address;
 
-	clear_siginfo(&siginfo);
 	rv.fkt = (unsigned long) -1;
 
 	/*
@@ -198,39 +196,22 @@ ia64_emulate_brl (struct pt_regs *regs, unsigned long ar_ec)
 		 *  The target address contains unimplemented bits.
 		 */
 		printk(KERN_DEBUG "Woah! Unimplemented Instruction Address Trap!\n");
-		siginfo.si_signo = SIGILL;
-		siginfo.si_errno = 0;
-		siginfo.si_flags = 0;
-		siginfo.si_isr = 0;
-		siginfo.si_imm = 0;
-		siginfo.si_code = ILL_BADIADDR;
-		force_sig_info(SIGILL, &siginfo, current);
+		force_sig_fault(SIGILL, ILL_BADIADDR, (void __user *)NULL,
+				0, 0, 0, current);
 	} else if (ia64_psr(regs)->tb) {
 		/*
 		 *  Branch Tracing is enabled.
 		 *  Force a taken branch signal.
 		 */
-		siginfo.si_signo = SIGTRAP;
-		siginfo.si_errno = 0;
-		siginfo.si_code = TRAP_BRANCH;
-		siginfo.si_flags = 0;
-		siginfo.si_isr = 0;
-		siginfo.si_addr = 0;
-		siginfo.si_imm = 0;
-		force_sig_info(SIGTRAP, &siginfo, current);
+		force_sig_fault(SIGTRAP, TRAP_BRANCH, (void __user *)NULL,
+				0, 0, 0, current);
 	} else if (ia64_psr(regs)->ss) {
 		/*
 		 *  Single Step is enabled.
 		 *  Force a trace signal.
 		 */
-		siginfo.si_signo = SIGTRAP;
-		siginfo.si_errno = 0;
-		siginfo.si_code = TRAP_TRACE;
-		siginfo.si_flags = 0;
-		siginfo.si_isr = 0;
-		siginfo.si_addr = 0;
-		siginfo.si_imm = 0;
-		force_sig_info(SIGTRAP, &siginfo, current);
+		force_sig_fault(SIGTRAP, TRAP_TRACE, (void __user *)NULL,
+				0, 0, 0, current);
 	}
 	return rv;
 }
diff --git a/arch/ia64/kernel/traps.c b/arch/ia64/kernel/traps.c
index c6f4932073a1..85d8616ac4f6 100644
--- a/arch/ia64/kernel/traps.c
+++ b/arch/ia64/kernel/traps.c
@@ -100,16 +100,8 @@ die_if_kernel (char *str, struct pt_regs *regs, long err)
 void
 __kprobes ia64_bad_break (unsigned long break_num, struct pt_regs *regs)
 {
-	siginfo_t siginfo;
 	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 */
-	siginfo.si_isr = 0;
-
 	switch (break_num) {
 	      case 0: /* unknown error (used by GCC for __builtin_abort()) */
 		if (notify_die(DIE_BREAK, "break 0", regs, break_num, TRAP_BRKPT, SIGTRAP)
@@ -182,10 +174,9 @@ __kprobes ia64_bad_break (unsigned long break_num, struct pt_regs *regs)
 			sig = SIGTRAP; code = TRAP_BRKPT;
 		}
 	}
-	siginfo.si_signo = sig;
-	siginfo.si_errno = 0;
-	siginfo.si_code = code;
-	force_sig_info(sig, &siginfo, current);
+	force_sig_fault(sig, code,
+			(void __user *) (regs->cr_iip + ia64_psr(regs)->ri),
+			break_num, 0 /* clear __ISR_VALID */, 0, current);
 }
 
 /*
@@ -344,30 +335,25 @@ 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? */
+			int si_code;
+
 			if (exception & 2) {
 				ia64_increment_ip(regs);
 			}
-			clear_siginfo(&siginfo);
-			siginfo.si_signo = SIGFPE;
-			siginfo.si_errno = 0;
-			siginfo.si_code = FPE_FLTUNK;	/* default code */
-			siginfo.si_addr = (void __user *) (regs->cr_iip + ia64_psr(regs)->ri);
+			si_code = FPE_FLTUNK;	/* default code */
 			if (isr & 0x11) {
-				siginfo.si_code = FPE_FLTINV;
+				si_code = FPE_FLTINV;
 			} else if (isr & 0x22) {
 				/* denormal operand gets the same si_code as underflow 
 				* see arch/i386/kernel/traps.c:math_error()  */
-				siginfo.si_code = FPE_FLTUND;
+				si_code = FPE_FLTUND;
 			} else if (isr & 0x44) {
-				siginfo.si_code = FPE_FLTDIV;
+				si_code = FPE_FLTDIV;
 			}
-			siginfo.si_isr = isr;
-			siginfo.si_flags = __ISR_VALID;
-			siginfo.si_imm = 0;
-			force_sig_info(SIGFPE, &siginfo, current);
+			force_sig_fault(SIGFPE, si_code,
+					(void __user *) (regs->cr_iip + ia64_psr(regs)->ri),
+					0, __ISR_VALID, isr, current);
 		}
 	} else {
 		if (exception == -1) {
@@ -375,24 +361,19 @@ handle_fpu_swa (int fp_fault, struct pt_regs *regs, unsigned long isr)
 			return -1;
 		} else if (exception != 0) {
 			/* raise exception */
-			struct siginfo siginfo;
+			int si_code;
 
-			clear_siginfo(&siginfo);
-			siginfo.si_signo = SIGFPE;
-			siginfo.si_errno = 0;
-			siginfo.si_code = FPE_FLTUNK;	/* default code */
-			siginfo.si_addr = (void __user *) (regs->cr_iip + ia64_psr(regs)->ri);
+			si_code = FPE_FLTUNK;	/* default code */
 			if (isr & 0x880) {
-				siginfo.si_code = FPE_FLTOVF;
+				si_code = FPE_FLTOVF;
 			} else if (isr & 0x1100) {
-				siginfo.si_code = FPE_FLTUND;
+				si_code = FPE_FLTUND;
 			} else if (isr & 0x2200) {
-				siginfo.si_code = FPE_FLTRES;
+				si_code = FPE_FLTRES;
 			}
-			siginfo.si_isr = isr;
-			siginfo.si_flags = __ISR_VALID;
-			siginfo.si_imm = 0;
-			force_sig_info(SIGFPE, &siginfo, current);
+			force_sig_fault(SIGFPE, si_code,
+					(void __user *) (regs->cr_iip + ia64_psr(regs)->ri),
+					0, __ISR_VALID, isr, current);
 		}
 	}
 	return 0;
@@ -408,7 +389,6 @@ ia64_illegal_op_fault (unsigned long ec, long arg1, long arg2, long arg3,
 		       struct pt_regs regs)
 {
 	struct illegal_op_return rv;
-	struct siginfo si;
 	char buf[128];
 
 #ifdef CONFIG_IA64_BRL_EMU
@@ -426,11 +406,9 @@ ia64_illegal_op_fault (unsigned long ec, long arg1, long arg2, long arg3,
 	if (die_if_kernel(buf, &regs, 0))
 		return rv;
 
-	clear_siginfo(&si);
-	si.si_signo = SIGILL;
-	si.si_code = ILL_ILLOPC;
-	si.si_addr = (void __user *) (regs.cr_iip + ia64_psr(&regs)->ri);
-	force_sig_info(SIGILL, &si, current);
+	force_sig_fault(SIGILL, ILL_ILLOPC,
+			(void __user *) (regs.cr_iip + ia64_psr(&regs)->ri),
+			0, 0, 0, current);
 	return rv;
 }
 
@@ -441,7 +419,7 @@ ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa,
 {
 	unsigned long code, error = isr, iip;
 	char buf[128];
-	int result, sig;
+	int result, sig, si_code;
 	static const char *reason[] = {
 		"IA-64 Illegal Operation fault",
 		"IA-64 Privileged Operation fault",
@@ -490,7 +468,6 @@ 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) {
@@ -505,15 +482,8 @@ 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;
-			siginfo.si_addr = addr;
-			siginfo.si_imm = vector;
-			siginfo.si_flags = __ISR_VALID;
-			siginfo.si_isr = isr;
-			force_sig_info(sig, &siginfo, current);
+			force_sig_fault(sig, code, addr,
+					vector, __ISR_VALID, isr, current);
 			return;
 		} else if (ia64_done_with_exception(&regs))
 			return;
@@ -522,17 +492,8 @@ 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;
-			siginfo.si_addr = (void __user *) iip;
-			siginfo.si_imm = vector;
-			siginfo.si_flags = __ISR_VALID;
-			siginfo.si_isr = isr;
-			force_sig_info(SIGILL, &siginfo, current);
+			force_sig_fault(SIGILL, ILL_ILLOPN, (void __user *) iip,
+					vector, __ISR_VALID, isr, current);
 			return;
 		}
 		sprintf(buf, "Unsupported data reference");
@@ -541,10 +502,6 @@ 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[];
 			/*
@@ -568,7 +525,7 @@ ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa,
 		switch (vector) {
 		      default:
 		      case 29:
-			siginfo.si_code = TRAP_HWBKPT;
+			si_code = TRAP_HWBKPT;
 #ifdef CONFIG_ITANIUM
 			/*
 			 * Erratum 10 (IFA may contain incorrect address) now has
@@ -578,37 +535,22 @@ ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa,
 			  ifa = regs.cr_iip;
 #endif
 			break;
-		      case 35: siginfo.si_code = TRAP_BRANCH; ifa = 0; break;
-		      case 36: siginfo.si_code = TRAP_TRACE; ifa = 0; break;
+		      case 35: si_code = TRAP_BRANCH; ifa = 0; break;
+		      case 36: si_code = TRAP_TRACE; ifa = 0; break;
 		}
-		if (notify_die(DIE_FAULT, "ia64_fault", &regs, vector, siginfo.si_code, SIGTRAP)
+		if (notify_die(DIE_FAULT, "ia64_fault", &regs, vector, si_code, SIGTRAP)
 			       	== NOTIFY_STOP)
 			return;
-		siginfo.si_signo = SIGTRAP;
-		siginfo.si_errno = 0;
-		siginfo.si_addr  = (void __user *) ifa;
-		siginfo.si_imm   = 0;
-		siginfo.si_flags = __ISR_VALID;
-		siginfo.si_isr   = isr;
-		force_sig_info(SIGTRAP, &siginfo, current);
+		force_sig_fault(SIGTRAP, si_code, (void __user *) ifa,
+				0, __ISR_VALID, isr, 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;
-			siginfo.si_addr = (void __user *) iip;
-			siginfo.si_flags = __ISR_VALID;
-			siginfo.si_isr = isr;
-			siginfo.si_imm = 0;
-			force_sig_info(SIGFPE, &siginfo, current);
+			force_sig_fault(SIGFPE, FPE_FLTINV, (void __user *) iip,
+					0, __ISR_VALID, isr, current);
 		}
 		return;
 
@@ -634,17 +576,9 @@ 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;
-				siginfo.si_flags = 0;
-				siginfo.si_isr = 0;
-				siginfo.si_imm = 0;
-				siginfo.si_addr = (void __user *) iip;
-				force_sig_info(SIGILL, &siginfo, current);
+				force_sig_fault(SIGILL, ILL_BADIADDR,
+						(void __user *) iip,
+						0, 0, 0, current);
 				return;
 			}
 			sprintf(buf, "Unimplemented Instruction Address fault");
diff --git a/arch/ia64/kernel/unaligned.c b/arch/ia64/kernel/unaligned.c
index e309f9859acc..a167a3824b35 100644
--- a/arch/ia64/kernel/unaligned.c
+++ b/arch/ia64/kernel/unaligned.c
@@ -1298,7 +1298,6 @@ ia64_handle_unaligned (unsigned long ifa, struct pt_regs *regs)
 	mm_segment_t old_fs = get_fs();
 	unsigned long bundle[2];
 	unsigned long opcode;
-	struct siginfo si;
 	const struct exception_table_entry *eh = NULL;
 	union {
 		unsigned long l;
@@ -1537,14 +1536,7 @@ 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;
-	si.si_addr = (void __user *) ifa;
-	si.si_flags = 0;
-	si.si_isr = 0;
-	si.si_imm = 0;
-	force_sig_info(SIGBUS, &si, current);
+	force_sig_fault(SIGBUS, BUS_ADRALN, (void __user *) ifa,
+			0, 0, 0, current);
 	goto done;
 }
diff --git a/arch/ia64/mm/fault.c b/arch/ia64/mm/fault.c
index a9d55ad8d67b..5baeb022f474 100644
--- a/arch/ia64/mm/fault.c
+++ b/arch/ia64/mm/fault.c
@@ -248,16 +248,8 @@ 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;
-		si.si_addr = (void __user *) address;
-		si.si_isr = isr;
-		si.si_flags = __ISR_VALID;
-		force_sig_info(signal, &si, current);
+		force_sig_fault(signal, code, (void __user *) address,
+				0, __ISR_VALID, isr, current);
 		return;
 	}
 
-- 
2.17.1