From 6fa998e83ef9bcc479b0fa088de262a73e139bf8 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Fri, 21 Sep 2018 17:24:40 +0200
Subject: signal/arm64: Push siginfo generation into arm64_notify_die

Instead of generating a struct siginfo before calling arm64_notify_die
pass the signal number, tne sicode and the fault address into
arm64_notify_die and have it call force_sig_fault instead of
force_sig_info to let the generic code generate the struct siginfo.

This keeps code passing just the needed information into
siginfo generating code, making it easier to see what
is happening and harder to get wrong.  Further by letting
the generic code handle the generation of struct siginfo
it reduces the number of sites generating struct siginfo
making it possible to review them and verify that all
of the fiddly details for a structure passed to userspace
are handled properly.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/arm64/mm/fault.c | 41 ++++++++++-------------------------------
 1 file changed, 10 insertions(+), 31 deletions(-)

(limited to 'arch/arm64/mm/fault.c')

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 50b30ff30de4..86fe70d8722f 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -625,8 +625,8 @@ static int do_bad(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 
 static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 {
-	struct siginfo info;
 	const struct fault_info *inf;
+	void __user *siaddr;
 
 	inf = esr_to_fault_info(esr);
 
@@ -645,15 +645,11 @@ 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;
 	if (esr & ESR_ELx_FnV)
-		info.si_addr = NULL;
+		siaddr = NULL;
 	else
-		info.si_addr  = (void __user *)addr;
-	arm64_notify_die(inf->name, regs, &info, esr);
+		siaddr  = (void __user *)addr;
+	arm64_notify_die(inf->name, regs, inf->sig, inf->code, siaddr, esr);
 
 	return 0;
 }
@@ -734,7 +730,6 @@ asmlinkage void __exception do_mem_abort(unsigned long addr, unsigned int esr,
 					 struct pt_regs *regs)
 {
 	const struct fault_info *inf = esr_to_fault_info(esr);
-	struct siginfo info;
 
 	if (!inf->fn(addr, esr, regs))
 		return;
@@ -745,12 +740,8 @@ 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;
-	info.si_addr  = (void __user *)addr;
-	arm64_notify_die(inf->name, regs, &info, esr);
+	arm64_notify_die(inf->name, regs,
+			 inf->sig, inf->code, (void __user *)addr, esr);
 }
 
 asmlinkage void __exception do_el0_irq_bp_hardening(void)
@@ -780,20 +771,14 @@ asmlinkage void __exception do_sp_pc_abort(unsigned long addr,
 					   unsigned int esr,
 					   struct pt_regs *regs)
 {
-	struct siginfo info;
-
 	if (user_mode(regs)) {
 		if (instruction_pointer(regs) > TASK_SIZE)
 			arm64_apply_bp_hardening();
 		local_irq_enable();
 	}
 
-	clear_siginfo(&info);
-	info.si_signo = SIGBUS;
-	info.si_errno = 0;
-	info.si_code  = BUS_ADRALN;
-	info.si_addr  = (void __user *)addr;
-	arm64_notify_die("SP/PC alignment exception", regs, &info, esr);
+	arm64_notify_die("SP/PC alignment exception", regs,
+			 SIGBUS, BUS_ADRALN, (void __user *)addr, esr);
 }
 
 int __init early_brk64(unsigned long addr, unsigned int esr,
@@ -847,14 +832,8 @@ 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;
-		info.si_addr  = (void __user *)addr;
-		arm64_notify_die(inf->name, regs, &info, esr);
+		arm64_notify_die(inf->name, regs,
+				 inf->sig, inf->code, (void __user *)addr, esr);
 		rv = 0;
 	}
 
-- 
cgit v1.2.3


From 24b8f79dd8e036da618d158b4c0295208d478c5c Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Sat, 22 Sep 2018 00:38:41 +0200
Subject: signal/arm64: Remove unneeded tsk parameter from arm64_force_sig_info

Every caller passes in current for tsk so there is no need to pass
tsk.  Instead make tsk a local variable initialized to current.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/arm64/include/asm/traps.h     | 3 +--
 arch/arm64/kernel/debug-monitors.c | 2 +-
 arch/arm64/kernel/ptrace.c         | 2 +-
 arch/arm64/kernel/traps.c          | 8 ++++----
 arch/arm64/mm/fault.c              | 2 +-
 5 files changed, 8 insertions(+), 9 deletions(-)

(limited to 'arch/arm64/mm/fault.c')

diff --git a/arch/arm64/include/asm/traps.h b/arch/arm64/include/asm/traps.h
index c320f3bf6c57..cd3a2ca9c179 100644
--- a/arch/arm64/include/asm/traps.h
+++ b/arch/arm64/include/asm/traps.h
@@ -37,8 +37,7 @@ void register_undef_hook(struct undef_hook *hook);
 void unregister_undef_hook(struct undef_hook *hook);
 void force_signal_inject(int signal, int code, unsigned long address);
 void arm64_notify_segfault(unsigned long addr);
-void arm64_force_sig_info(struct siginfo *info, const char *str,
-			  struct task_struct *tsk);
+void arm64_force_sig_info(struct siginfo *info, const char *str);
 
 /*
  * Move regs->pc to next instruction and do necessary setup before it
diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index 06ca574495af..e0d9502be5bf 100644
--- a/arch/arm64/kernel/debug-monitors.c
+++ b/arch/arm64/kernel/debug-monitors.c
@@ -224,7 +224,7 @@ static void send_user_sigtrap(int si_code)
 	if (interrupts_enabled(regs))
 		local_irq_enable();
 
-	arm64_force_sig_info(&info, "User debug trap", current);
+	arm64_force_sig_info(&info, "User debug trap");
 }
 
 static int single_step_handler(unsigned long addr, unsigned int esr,
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 6219486fa25f..20b68cb31ecb 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -211,7 +211,7 @@ static void ptrace_hbptriggered(struct perf_event *bp,
 		force_sig_ptrace_errno_trap(si_errno, (void __user *)bkpt->trigger);
 	}
 #endif
-	arm64_force_sig_info(&info, "Hardware breakpoint trap (ptrace)", current);
+	arm64_force_sig_info(&info, "Hardware breakpoint trap (ptrace)");
 }
 
 /*
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 459eb6fb7158..24035d124608 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -231,9 +231,9 @@ static bool show_unhandled_signals_ratelimited(void)
 	return show_unhandled_signals && __ratelimit(&rs);
 }
 
-void arm64_force_sig_info(struct siginfo *info, const char *str,
-			  struct task_struct *tsk)
+void arm64_force_sig_info(struct siginfo *info, const char *str)
 {
+	struct task_struct *tsk = current;
 	unsigned int esr = tsk->thread.fault_code;
 	struct pt_regs *regs = task_pt_regs(tsk);
 
@@ -273,7 +273,7 @@ void arm64_notify_die(const char *str, struct pt_regs *regs,
 		info.si_code  = sicode;
 		info.si_addr  = addr;
 
-		arm64_force_sig_info(&info, str, current);
+		arm64_force_sig_info(&info, str);
 	} else {
 		die(str, regs, err);
 	}
@@ -630,7 +630,7 @@ asmlinkage void bad_el0_sync(struct pt_regs *regs, int reason, unsigned int esr)
 	current->thread.fault_address = 0;
 	current->thread.fault_code = esr;
 
-	arm64_force_sig_info(&info, "Bad EL0 synchronous exception", current);
+	arm64_force_sig_info(&info, "Bad EL0 synchronous exception");
 }
 
 #ifdef CONFIG_VMAP_STACK
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 86fe70d8722f..f42aff0e90ad 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -352,7 +352,7 @@ static void __do_user_fault(struct siginfo *info, unsigned int esr)
 	}
 
 	current->thread.fault_code = esr;
-	arm64_force_sig_info(info, esr_to_fault_info(esr)->name, current);
+	arm64_force_sig_info(info, esr_to_fault_info(esr)->name);
 }
 
 static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *regs)
-- 
cgit v1.2.3


From f29ad209e428f5bc596de39dd9b8d73db5739920 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Sat, 22 Sep 2018 09:37:55 +0200
Subject: signal/arm64: Factor set_thread_esr out of __do_user_fault

This pepares for sending signals with something other than
arm64_force_sig_info.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/arm64/mm/fault.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

(limited to 'arch/arm64/mm/fault.c')

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index f42aff0e90ad..654a861c4bd0 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -297,9 +297,9 @@ static void __do_kernel_fault(unsigned long addr, unsigned int esr,
 	die_kernel_fault(msg, addr, esr, regs);
 }
 
-static void __do_user_fault(struct siginfo *info, unsigned int esr)
+static void set_thread_esr(unsigned long address, unsigned int esr)
 {
-	current->thread.fault_address = (unsigned long)info->si_addr;
+	current->thread.fault_address = address;
 
 	/*
 	 * If the faulting address is in the kernel, we must sanitize the ESR.
@@ -352,6 +352,11 @@ static void __do_user_fault(struct siginfo *info, unsigned int esr)
 	}
 
 	current->thread.fault_code = esr;
+}
+
+static void __do_user_fault(struct siginfo *info, unsigned int esr)
+{
+	set_thread_esr((unsigned long)info->si_addr, esr);
 	arm64_force_sig_info(info, esr_to_fault_info(esr)->name);
 }
 
-- 
cgit v1.2.3


From 9ea3a9743cac4fd2e296223ae6a95bf11d7365d0 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Sat, 22 Sep 2018 09:46:39 +0200
Subject: signal/arm64: Consolidate the two hwpoison cases in do_page_fault

These two cases are practically the same and use siginfo differently
from the other signals sent from do_page_fault.  So consolidate them
to make future changes easier.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/arm64/mm/fault.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

(limited to 'arch/arm64/mm/fault.c')

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 654a861c4bd0..0ddc8c6ba53b 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -577,16 +577,16 @@ retry:
 		 */
 		si.si_signo	= SIGBUS;
 		si.si_code	= BUS_ADRERR;
-	} else if (fault & VM_FAULT_HWPOISON_LARGE) {
-		unsigned int hindex = VM_FAULT_GET_HINDEX(fault);
+	} else if (fault & (VM_FAULT_HWPOISON_LARGE | VM_FAULT_HWPOISON)) {
+		unsigned int lsb;
+
+		lsb = PAGE_SHIFT;
+		if (fault & VM_FAULT_HWPOISON_LARGE)
+			lsb = hstate_index_to_shift(VM_FAULT_GET_HINDEX(fault));
 
 		si.si_signo	= SIGBUS;
 		si.si_code	= BUS_MCEERR_AR;
-		si.si_addr_lsb	= hstate_index_to_shift(hindex);
-	} else if (fault & VM_FAULT_HWPOISON) {
-		si.si_signo	= SIGBUS;
-		si.si_code	= BUS_MCEERR_AR;
-		si.si_addr_lsb	= PAGE_SHIFT;
+		si.si_addr_lsb	= lsb;
 	} else {
 		/*
 		 * Something tried to access memory that isn't in our memory
-- 
cgit v1.2.3


From aefab2b4c01ee67f2b60e400e46bad63d29c2603 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Sat, 22 Sep 2018 09:54:33 +0200
Subject: signal/arm64: For clarity separate the 3 signal sending cases in
 do_page_fault

It gets easy to confuse what is going on when some code is shared and some not
so stop sharing the trivial bits of signal generation to make future updates
easier to understand.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/arm64/mm/fault.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

(limited to 'arch/arm64/mm/fault.c')

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 0ddc8c6ba53b..14d6ff895139 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -567,16 +567,16 @@ retry:
 		return 0;
 	}
 
-	clear_siginfo(&si);
-	si.si_addr = (void __user *)addr;
-
 	if (fault & VM_FAULT_SIGBUS) {
 		/*
 		 * We had some memory, but were unable to successfully fix up
 		 * this page fault.
 		 */
+		clear_siginfo(&si);
 		si.si_signo	= SIGBUS;
 		si.si_code	= BUS_ADRERR;
+		si.si_addr = (void __user *)addr;
+		__do_user_fault(&si, esr);
 	} else if (fault & (VM_FAULT_HWPOISON_LARGE | VM_FAULT_HWPOISON)) {
 		unsigned int lsb;
 
@@ -584,20 +584,25 @@ retry:
 		if (fault & VM_FAULT_HWPOISON_LARGE)
 			lsb = hstate_index_to_shift(VM_FAULT_GET_HINDEX(fault));
 
+		clear_siginfo(&si);
 		si.si_signo	= SIGBUS;
 		si.si_code	= BUS_MCEERR_AR;
+		si.si_addr = (void __user *)addr;
 		si.si_addr_lsb	= lsb;
+		__do_user_fault(&si, esr);
 	} else {
 		/*
 		 * Something tried to access memory that isn't in our memory
 		 * map.
 		 */
+		clear_siginfo(&si);
 		si.si_signo	= SIGSEGV;
 		si.si_code	= fault == VM_FAULT_BADACCESS ?
 				  SEGV_ACCERR : SEGV_MAPERR;
+		si.si_addr = (void __user *)addr;
+		__do_user_fault(&si, esr);
 	}
 
-	__do_user_fault(&si, esr);
 	return 0;
 
 no_context:
-- 
cgit v1.2.3


From effb093ad28b69230aad222650ec954a21c06ede Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Sat, 22 Sep 2018 10:05:41 +0200
Subject: signal/arm64: Expand __do_user_fault and remove it

Not all of the signals passed to __do_user_fault can be handled
the same way so expand the now tiny __do_user_fault in it's callers
and remove it.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/arm64/mm/fault.c | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

(limited to 'arch/arm64/mm/fault.c')

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 14d6ff895139..7df3d8b561c2 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -354,12 +354,6 @@ static void set_thread_esr(unsigned long address, unsigned int esr)
 	current->thread.fault_code = esr;
 }
 
-static void __do_user_fault(struct siginfo *info, unsigned int esr)
-{
-	set_thread_esr((unsigned long)info->si_addr, esr);
-	arm64_force_sig_info(info, esr_to_fault_info(esr)->name);
-}
-
 static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 {
 	/*
@@ -375,7 +369,8 @@ static void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *re
 		si.si_code	= inf->code;
 		si.si_addr	= (void __user *)addr;
 
-		__do_user_fault(&si, esr);
+		set_thread_esr(addr, esr);
+		arm64_force_sig_info(&si, inf->name);
 	} else {
 		__do_kernel_fault(addr, esr, regs);
 	}
@@ -576,7 +571,8 @@ retry:
 		si.si_signo	= SIGBUS;
 		si.si_code	= BUS_ADRERR;
 		si.si_addr = (void __user *)addr;
-		__do_user_fault(&si, esr);
+		set_thread_esr(addr, esr);
+		arm64_force_sig_info(&si, esr_to_fault_info(esr)->name);
 	} else if (fault & (VM_FAULT_HWPOISON_LARGE | VM_FAULT_HWPOISON)) {
 		unsigned int lsb;
 
@@ -589,7 +585,8 @@ retry:
 		si.si_code	= BUS_MCEERR_AR;
 		si.si_addr = (void __user *)addr;
 		si.si_addr_lsb	= lsb;
-		__do_user_fault(&si, esr);
+		set_thread_esr(addr, esr);
+		arm64_force_sig_info(&si, esr_to_fault_info(esr)->name);
 	} else {
 		/*
 		 * Something tried to access memory that isn't in our memory
@@ -600,7 +597,8 @@ retry:
 		si.si_code	= fault == VM_FAULT_BADACCESS ?
 				  SEGV_ACCERR : SEGV_MAPERR;
 		si.si_addr = (void __user *)addr;
-		__do_user_fault(&si, esr);
+		set_thread_esr(addr, esr);
+		arm64_force_sig_info(&si, esr_to_fault_info(esr)->name);
 	}
 
 	return 0;
-- 
cgit v1.2.3


From 2d2837fab5fadaf6942e834c2cbe8c9e594917c1 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Sat, 22 Sep 2018 10:16:42 +0200
Subject: signal/arm64: Only perform one esr_to_fault_info call in
 do_page_fault

As this work is truly common between all of the signal sending cases
there is no need to repeat it between the different cases.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
---
 arch/arm64/mm/fault.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

(limited to 'arch/arm64/mm/fault.c')

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 7df3d8b561c2..ab85533e2255 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -424,6 +424,7 @@ static bool is_el0_instruction_abort(unsigned int esr)
 static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
 				   struct pt_regs *regs)
 {
+	const struct fault_info *inf;
 	struct task_struct *tsk;
 	struct mm_struct *mm;
 	struct siginfo si;
@@ -562,6 +563,7 @@ retry:
 		return 0;
 	}
 
+	inf = esr_to_fault_info(esr);
 	if (fault & VM_FAULT_SIGBUS) {
 		/*
 		 * We had some memory, but were unable to successfully fix up
@@ -572,7 +574,7 @@ retry:
 		si.si_code	= BUS_ADRERR;
 		si.si_addr = (void __user *)addr;
 		set_thread_esr(addr, esr);
-		arm64_force_sig_info(&si, esr_to_fault_info(esr)->name);
+		arm64_force_sig_info(&si, inf->name);
 	} else if (fault & (VM_FAULT_HWPOISON_LARGE | VM_FAULT_HWPOISON)) {
 		unsigned int lsb;
 
@@ -586,7 +588,7 @@ retry:
 		si.si_addr = (void __user *)addr;
 		si.si_addr_lsb	= lsb;
 		set_thread_esr(addr, esr);
-		arm64_force_sig_info(&si, esr_to_fault_info(esr)->name);
+		arm64_force_sig_info(&si, inf->name);
 	} else {
 		/*
 		 * Something tried to access memory that isn't in our memory
@@ -598,7 +600,7 @@ retry:
 				  SEGV_ACCERR : SEGV_MAPERR;
 		si.si_addr = (void __user *)addr;
 		set_thread_esr(addr, esr);
-		arm64_force_sig_info(&si, esr_to_fault_info(esr)->name);
+		arm64_force_sig_info(&si, inf->name);
 	}
 
 	return 0;
-- 
cgit v1.2.3


From 559d8d91a89cc2a0190781a5b5ce3faeaef7920f Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Sat, 22 Sep 2018 10:18:42 +0200
Subject: signal/arm64: Only call set_thread_esr once in do_page_fault

This code is truly common between the signal sending cases so share it.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
---
 arch/arm64/mm/fault.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

(limited to 'arch/arm64/mm/fault.c')

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index ab85533e2255..959c4a565c8e 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -564,6 +564,7 @@ retry:
 	}
 
 	inf = esr_to_fault_info(esr);
+	set_thread_esr(addr, esr);
 	if (fault & VM_FAULT_SIGBUS) {
 		/*
 		 * We had some memory, but were unable to successfully fix up
@@ -573,7 +574,6 @@ retry:
 		si.si_signo	= SIGBUS;
 		si.si_code	= BUS_ADRERR;
 		si.si_addr = (void __user *)addr;
-		set_thread_esr(addr, esr);
 		arm64_force_sig_info(&si, inf->name);
 	} else if (fault & (VM_FAULT_HWPOISON_LARGE | VM_FAULT_HWPOISON)) {
 		unsigned int lsb;
@@ -587,7 +587,6 @@ retry:
 		si.si_code	= BUS_MCEERR_AR;
 		si.si_addr = (void __user *)addr;
 		si.si_addr_lsb	= lsb;
-		set_thread_esr(addr, esr);
 		arm64_force_sig_info(&si, inf->name);
 	} else {
 		/*
@@ -599,7 +598,6 @@ retry:
 		si.si_code	= fault == VM_FAULT_BADACCESS ?
 				  SEGV_ACCERR : SEGV_MAPERR;
 		si.si_addr = (void __user *)addr;
-		set_thread_esr(addr, esr);
 		arm64_force_sig_info(&si, inf->name);
 	}
 
-- 
cgit v1.2.3


From feca355b3d8eba3a2cbca63c97a59a14681983f7 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Sat, 22 Sep 2018 10:26:57 +0200
Subject: signal/arm64: Add and use arm64_force_sig_fault where appropriate

Wrap force_sig_fault with a helper that calls arm64_show_signal
and call arm64_force_sig_fault where appropraite.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
---
 arch/arm64/include/asm/traps.h     |  1 +
 arch/arm64/kernel/debug-monitors.c | 11 +++--------
 arch/arm64/kernel/ptrace.c         | 11 +++--------
 arch/arm64/kernel/traps.c          | 27 ++++++++++-----------------
 arch/arm64/mm/fault.c              | 26 ++++++++------------------
 5 files changed, 25 insertions(+), 51 deletions(-)

(limited to 'arch/arm64/mm/fault.c')

diff --git a/arch/arm64/include/asm/traps.h b/arch/arm64/include/asm/traps.h
index cd3a2ca9c179..08e99901edbc 100644
--- a/arch/arm64/include/asm/traps.h
+++ b/arch/arm64/include/asm/traps.h
@@ -37,6 +37,7 @@ void register_undef_hook(struct undef_hook *hook);
 void unregister_undef_hook(struct undef_hook *hook);
 void force_signal_inject(int signal, int code, unsigned long address);
 void arm64_notify_segfault(unsigned long addr);
+void arm64_force_sig_fault(int signo, int code, void __user *addr, const char *str);
 void arm64_force_sig_info(struct siginfo *info, const char *str);
 
 /*
diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index e0d9502be5bf..d7bb6aefae0a 100644
--- a/arch/arm64/kernel/debug-monitors.c
+++ b/arch/arm64/kernel/debug-monitors.c
@@ -210,13 +210,6 @@ NOKPROBE_SYMBOL(call_step_hook);
 static void send_user_sigtrap(int si_code)
 {
 	struct pt_regs *regs = current_pt_regs();
-	siginfo_t info;
-
-	clear_siginfo(&info);
-	info.si_signo	= SIGTRAP;
-	info.si_errno	= 0;
-	info.si_code	= si_code;
-	info.si_addr	= (void __user *)instruction_pointer(regs);
 
 	if (WARN_ON(!user_mode(regs)))
 		return;
@@ -224,7 +217,9 @@ static void send_user_sigtrap(int si_code)
 	if (interrupts_enabled(regs))
 		local_irq_enable();
 
-	arm64_force_sig_info(&info, "User debug trap");
+	arm64_force_sig_fault(SIGTRAP, si_code,
+			     (void __user *)instruction_pointer(regs),
+			     "User debug trap");
 }
 
 static int single_step_handler(unsigned long addr, unsigned int esr,
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 20b68cb31ecb..7ab75e78aa08 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -182,13 +182,6 @@ static void ptrace_hbptriggered(struct perf_event *bp,
 				struct pt_regs *regs)
 {
 	struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp);
-	siginfo_t info;
-
-	clear_siginfo(&info);
-	info.si_signo	= SIGTRAP;
-	info.si_errno	= 0;
-	info.si_code	= TRAP_HWBKPT;
-	info.si_addr	= (void __user *)(bkpt->trigger);
 
 #ifdef CONFIG_COMPAT
 	if (is_compat_task()) {
@@ -211,7 +204,9 @@ static void ptrace_hbptriggered(struct perf_event *bp,
 		force_sig_ptrace_errno_trap(si_errno, (void __user *)bkpt->trigger);
 	}
 #endif
-	arm64_force_sig_info(&info, "Hardware breakpoint trap (ptrace)");
+	arm64_force_sig_fault(SIGTRAP, TRAP_HWBKPT,
+			      (void __user *)(bkpt->trigger),
+			      "Hardware breakpoint trap (ptrace)");
 }
 
 /*
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index daee8c2ca561..37a3309863e0 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -248,6 +248,13 @@ static void arm64_show_signal(int signo, const char *str)
 	__show_regs(regs);
 }
 
+void arm64_force_sig_fault(int signo, int code, void __user *addr,
+			   const char *str)
+{
+	arm64_show_signal(signo, str);
+	force_sig_fault(signo, code, addr, current);
+}
+
 void arm64_force_sig_info(struct siginfo *info, const char *str)
 {
 	arm64_show_signal(info->si_signo, str);
@@ -259,19 +266,11 @@ void arm64_notify_die(const char *str, struct pt_regs *regs,
 		      int err)
 {
 	if (user_mode(regs)) {
-		struct siginfo info;
-
 		WARN_ON(regs != current_pt_regs());
 		current->thread.fault_address = 0;
 		current->thread.fault_code = err;
 
-		clear_siginfo(&info);
-		info.si_signo = signo;
-		info.si_errno = 0;
-		info.si_code  = sicode;
-		info.si_addr  = addr;
-
-		arm64_force_sig_info(&info, str);
+		arm64_force_sig_fault(signo, sicode, addr, str);
 	} else {
 		die(str, regs, err);
 	}
@@ -616,19 +615,13 @@ asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr)
  */
 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;
-	info.si_addr  = pc;
-
 	current->thread.fault_address = 0;
 	current->thread.fault_code = esr;
 
-	arm64_force_sig_info(&info, "Bad EL0 synchronous exception");
+	arm64_force_sig_fault(SIGILL, ILL_ILLOPC, pc,
+			      "Bad EL0 synchronous exception");
 }
 
 #ifdef CONFIG_VMAP_STACK
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 959c4a565c8e..66c295019a9a 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -362,15 +362,10 @@ 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;
-
-		clear_siginfo(&si);
-		si.si_signo	= inf->sig;
-		si.si_code	= inf->code;
-		si.si_addr	= (void __user *)addr;
 
 		set_thread_esr(addr, esr);
-		arm64_force_sig_info(&si, inf->name);
+		arm64_force_sig_fault(inf->sig, inf->code, (void __user *)addr,
+				      inf->name);
 	} else {
 		__do_kernel_fault(addr, esr, regs);
 	}
@@ -570,11 +565,8 @@ retry:
 		 * We had some memory, but were unable to successfully fix up
 		 * this page fault.
 		 */
-		clear_siginfo(&si);
-		si.si_signo	= SIGBUS;
-		si.si_code	= BUS_ADRERR;
-		si.si_addr = (void __user *)addr;
-		arm64_force_sig_info(&si, inf->name);
+		arm64_force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)addr,
+				      inf->name);
 	} else if (fault & (VM_FAULT_HWPOISON_LARGE | VM_FAULT_HWPOISON)) {
 		unsigned int lsb;
 
@@ -593,12 +585,10 @@ retry:
 		 * Something tried to access memory that isn't in our memory
 		 * map.
 		 */
-		clear_siginfo(&si);
-		si.si_signo	= SIGSEGV;
-		si.si_code	= fault == VM_FAULT_BADACCESS ?
-				  SEGV_ACCERR : SEGV_MAPERR;
-		si.si_addr = (void __user *)addr;
-		arm64_force_sig_info(&si, inf->name);
+		arm64_force_sig_fault(SIGSEGV,
+				      fault == VM_FAULT_BADACCESS ? SEGV_ACCERR : SEGV_MAPERR,
+				      (void __user *)addr,
+				      inf->name);
 	}
 
 	return 0;
-- 
cgit v1.2.3


From b4d5557caa07a01796ca8a2d756eeaa5308f6876 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Sat, 22 Sep 2018 10:37:15 +0200
Subject: signal/arm64: Add and use arm64_force_sig_mceerr as appropriate

Add arm64_force_sig_mceerr for consistency with arm64_force_sig_fault,
and use it in the one location that can take advantage of it.

This removes the fiddly filling out of siginfo before sending a signal
reporting an memory error to userspace.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/arm64/include/asm/traps.h | 1 +
 arch/arm64/kernel/traps.c      | 7 +++++++
 arch/arm64/mm/fault.c          | 9 ++-------
 3 files changed, 10 insertions(+), 7 deletions(-)

(limited to 'arch/arm64/mm/fault.c')

diff --git a/arch/arm64/include/asm/traps.h b/arch/arm64/include/asm/traps.h
index 08e99901edbc..193f0b0e8ee3 100644
--- a/arch/arm64/include/asm/traps.h
+++ b/arch/arm64/include/asm/traps.h
@@ -38,6 +38,7 @@ void unregister_undef_hook(struct undef_hook *hook);
 void force_signal_inject(int signal, int code, unsigned long address);
 void arm64_notify_segfault(unsigned long addr);
 void arm64_force_sig_fault(int signo, int code, void __user *addr, const char *str);
+void arm64_force_sig_mceerr(int code, void __user *addr, short lsb, const char *str);
 void arm64_force_sig_info(struct siginfo *info, const char *str);
 
 /*
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 37a3309863e0..baa96dfffeec 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -255,6 +255,13 @@ void arm64_force_sig_fault(int signo, int code, void __user *addr,
 	force_sig_fault(signo, code, addr, current);
 }
 
+void arm64_force_sig_mceerr(int code, void __user *addr, short lsb,
+			    const char *str)
+{
+	arm64_show_signal(SIGBUS, str);
+	force_sig_mceerr(code, addr, lsb, current);
+}
+
 void arm64_force_sig_info(struct siginfo *info, const char *str)
 {
 	arm64_show_signal(info->si_signo, str);
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 66c295019a9a..f0ccb209d181 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -422,7 +422,6 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
 	const struct fault_info *inf;
 	struct task_struct *tsk;
 	struct mm_struct *mm;
-	struct siginfo si;
 	vm_fault_t fault, major = 0;
 	unsigned long vm_flags = VM_READ | VM_WRITE;
 	unsigned int mm_flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
@@ -574,12 +573,8 @@ retry:
 		if (fault & VM_FAULT_HWPOISON_LARGE)
 			lsb = hstate_index_to_shift(VM_FAULT_GET_HINDEX(fault));
 
-		clear_siginfo(&si);
-		si.si_signo	= SIGBUS;
-		si.si_code	= BUS_MCEERR_AR;
-		si.si_addr = (void __user *)addr;
-		si.si_addr_lsb	= lsb;
-		arm64_force_sig_info(&si, inf->name);
+		arm64_force_sig_mceerr(BUS_MCEERR_AR, (void __user *)addr, lsb,
+				       inf->name);
 	} else {
 		/*
 		 * Something tried to access memory that isn't in our memory
-- 
cgit v1.2.3