diff mbox

[REVIEW,16/22] signal/sh: Use force_sig_fault where appropriate

Message ID 20180420143811.9994-16-ebiederm@xmission.com
State New, archived
Headers show

Commit Message

Eric W. Biederman April 20, 2018, 2:38 p.m. UTC
Filling in struct siginfo before calling force_sig_info a tedious and
error prone process, where once in a great while the wrong fields
are filled out, and siginfo has been inconsistently cleared.

Simplify this process by using the helper force_sig_fault.  Which
takes as a parameters all of the information it needs, ensures
all of the fiddly bits of filling in struct siginfo are done properly
and then calls force_sig_info.

In short about a 5 line reduction in code for every time force_sig_info
is called, which makes the calling function clearer.

Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: linux-sh@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 arch/sh/kernel/traps_32.c | 19 +++++--------------
 arch/sh/math-emu/math.c   |  9 ++-------
 arch/sh/mm/fault.c        | 10 +---------
 3 files changed, 8 insertions(+), 30 deletions(-)

Comments

Rich Felker April 20, 2018, 2:55 p.m. UTC | #1
On Fri, Apr 20, 2018 at 09:38:05AM -0500, Eric W. Biederman wrote:
> Filling in struct siginfo before calling force_sig_info a tedious and
> error prone process, where once in a great while the wrong fields
> are filled out, and siginfo has been inconsistently cleared.
> 
> Simplify this process by using the helper force_sig_fault.  Which
> takes as a parameters all of the information it needs, ensures
> all of the fiddly bits of filling in struct siginfo are done properly
> and then calls force_sig_info.
> 
> In short about a 5 line reduction in code for every time force_sig_info
> is called, which makes the calling function clearer.
> 
> Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
> Cc: Rich Felker <dalias@libc.org>
> Cc: linux-sh@vger.kernel.org
> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
> ---
>  arch/sh/kernel/traps_32.c | 19 +++++--------------
>  arch/sh/math-emu/math.c   |  9 ++-------
>  arch/sh/mm/fault.c        | 10 +---------
>  3 files changed, 8 insertions(+), 30 deletions(-)
> 
> diff --git a/arch/sh/kernel/traps_32.c b/arch/sh/kernel/traps_32.c
> index e85e59c3d6df..660a4bc17698 100644
> --- a/arch/sh/kernel/traps_32.c
> +++ b/arch/sh/kernel/traps_32.c
> @@ -477,7 +477,6 @@ asmlinkage void do_address_error(struct pt_regs *regs,
>  {
>  	unsigned long error_code = 0;
>  	mm_segment_t oldfs;
> -	siginfo_t info;
>  	insn_size_t instruction;
>  	int tmp;
>  
> @@ -537,12 +536,7 @@ 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;
> -		info.si_addr = (void __user *)address;
> -		force_sig_info(SIGBUS, &info, current);
> +		force_sig_fault(SIGBUS, si_code, (void __user *)address, current);
>  	} else {
>  		inc_unaligned_kernel_access();
>  
> @@ -599,20 +593,17 @@ int is_dsp_inst(struct pt_regs *regs)
>  #ifdef CONFIG_CPU_SH2A
>  asmlinkage void do_divide_error(unsigned long r4)
>  {
> -	siginfo_t info;
> +	int code;
>  
> -	clear_siginfo(&info);
>  	switch (r4) {
>  	case TRAP_DIVZERO_ERROR:
> -		info.si_code = FPE_INTDIV;
> +		code = FPE_INTDIV;
>  		break;
>  	case TRAP_DIVOVF_ERROR:
> -		info.si_code = FPE_INTOVF;
> +		code = FPE_INTOVF;
>  		break;
>  	}
> -
> -	info.si_signo = SIGFPE;
> -	force_sig_info(info.si_signo, &info, current);
> +	force_sig_fault(SIGFPE, code, NULL, current);
>  }
>  #endif
>  
> diff --git a/arch/sh/math-emu/math.c b/arch/sh/math-emu/math.c
> index d6d2213df078..a0fa8fc88739 100644
> --- a/arch/sh/math-emu/math.c
> +++ b/arch/sh/math-emu/math.c
> @@ -507,7 +507,6 @@ static int ieee_fpe_handler(struct pt_regs *regs)
>  	unsigned short insn = *(unsigned short *)regs->pc;
>  	unsigned short finsn;
>  	unsigned long nextpc;
> -	siginfo_t info;
>  	int nib[4] = {
>  		(insn >> 12) & 0xf,
>  		(insn >> 8) & 0xf,
> @@ -560,12 +559,8 @@ 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;
> -			info.si_addr = (void __user *)regs->pc;
> -			force_sig_info(SIGFPE, &info, tsk);
> +			force_sig_fault(SIGFPE, FPE_FLTINV,
> +					(void __user *)regs->pc, tsk);
>  		}
>  
>  		regs->pc = nextpc;
> diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c
> index 4c98b6f20e02..b8e7bb84b6b1 100644
> --- a/arch/sh/mm/fault.c
> +++ b/arch/sh/mm/fault.c
> @@ -42,15 +42,7 @@ static void
>  force_sig_info_fault(int si_signo, int si_code, unsigned long address,
>  		     struct task_struct *tsk)
>  {
> -	siginfo_t info;
> -
> -	clear_siginfo(&info);
> -	info.si_signo	= si_signo;
> -	info.si_errno	= 0;
> -	info.si_code	= si_code;
> -	info.si_addr	= (void __user *)address;
> -
> -	force_sig_info(si_signo, &info, tsk);
> +	force_sig_fault(si_signo, si_code, (void __user *)address, tsk);
>  }
>  
>  /*
> -- 
> 2.14.1

Acked-by: Rich Felker <dalias@libc.org>
--
To unsubscribe from this list: send the line "unsubscribe linux-sh" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Geert Uytterhoeven May 28, 2018, 9:19 a.m. UTC | #2
On Fri, Apr 20, 2018 at 4:55 PM, Rich Felker <dalias@libc.org> wrote:
> On Fri, Apr 20, 2018 at 09:38:05AM -0500, Eric W. Biederman wrote:
>> Filling in struct siginfo before calling force_sig_info a tedious and
>> error prone process, where once in a great while the wrong fields
>> are filled out, and siginfo has been inconsistently cleared.
>>
>> Simplify this process by using the helper force_sig_fault.  Which
>> takes as a parameters all of the information it needs, ensures
>> all of the fiddly bits of filling in struct siginfo are done properly
>> and then calls force_sig_info.
>>
>> In short about a 5 line reduction in code for every time force_sig_info
>> is called, which makes the calling function clearer.
>>
>> Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
>> Cc: Rich Felker <dalias@libc.org>
>> Cc: linux-sh@vger.kernel.org
>> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

>> --- a/arch/sh/kernel/traps_32.c
>> +++ b/arch/sh/kernel/traps_32.c

>> @@ -599,20 +593,17 @@ int is_dsp_inst(struct pt_regs *regs)
>>  #ifdef CONFIG_CPU_SH2A
>>  asmlinkage void do_divide_error(unsigned long r4)
>>  {
>> -     siginfo_t info;
>> +     int code;
>>
>> -     clear_siginfo(&info);
>>       switch (r4) {
>>       case TRAP_DIVZERO_ERROR:
>> -             info.si_code = FPE_INTDIV;
>> +             code = FPE_INTDIV;
>>               break;
>>       case TRAP_DIVOVF_ERROR:
>> -             info.si_code = FPE_INTOVF;
>> +             code = FPE_INTOVF;
>>               break;
>>       }
>> -
>> -     info.si_signo = SIGFPE;
>> -     force_sig_info(info.si_signo, &info, current);
>> +     force_sig_fault(SIGFPE, code, NULL, current);

/kisskb/src/arch/sh/kernel/traps_32.c:606:17: error: 'code' may be
used uninitialized in this function [-Werror=uninitialized]

http://kisskb.ellerman.id.au/kisskb/buildresult/13366052/
http://kisskb.ellerman.id.au/kisskb/buildresult/13366048/
http://kisskb.ellerman.id.au/kisskb/buildresult/13366072/

>>  }

> Acked-by: Rich Felker <dalias@libc.org>


Gr{oetje,eeting}s,

                        Geert
diff mbox

Patch

diff --git a/arch/sh/kernel/traps_32.c b/arch/sh/kernel/traps_32.c
index e85e59c3d6df..660a4bc17698 100644
--- a/arch/sh/kernel/traps_32.c
+++ b/arch/sh/kernel/traps_32.c
@@ -477,7 +477,6 @@  asmlinkage void do_address_error(struct pt_regs *regs,
 {
 	unsigned long error_code = 0;
 	mm_segment_t oldfs;
-	siginfo_t info;
 	insn_size_t instruction;
 	int tmp;
 
@@ -537,12 +536,7 @@  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;
-		info.si_addr = (void __user *)address;
-		force_sig_info(SIGBUS, &info, current);
+		force_sig_fault(SIGBUS, si_code, (void __user *)address, current);
 	} else {
 		inc_unaligned_kernel_access();
 
@@ -599,20 +593,17 @@  int is_dsp_inst(struct pt_regs *regs)
 #ifdef CONFIG_CPU_SH2A
 asmlinkage void do_divide_error(unsigned long r4)
 {
-	siginfo_t info;
+	int code;
 
-	clear_siginfo(&info);
 	switch (r4) {
 	case TRAP_DIVZERO_ERROR:
-		info.si_code = FPE_INTDIV;
+		code = FPE_INTDIV;
 		break;
 	case TRAP_DIVOVF_ERROR:
-		info.si_code = FPE_INTOVF;
+		code = FPE_INTOVF;
 		break;
 	}
-
-	info.si_signo = SIGFPE;
-	force_sig_info(info.si_signo, &info, current);
+	force_sig_fault(SIGFPE, code, NULL, current);
 }
 #endif
 
diff --git a/arch/sh/math-emu/math.c b/arch/sh/math-emu/math.c
index d6d2213df078..a0fa8fc88739 100644
--- a/arch/sh/math-emu/math.c
+++ b/arch/sh/math-emu/math.c
@@ -507,7 +507,6 @@  static int ieee_fpe_handler(struct pt_regs *regs)
 	unsigned short insn = *(unsigned short *)regs->pc;
 	unsigned short finsn;
 	unsigned long nextpc;
-	siginfo_t info;
 	int nib[4] = {
 		(insn >> 12) & 0xf,
 		(insn >> 8) & 0xf,
@@ -560,12 +559,8 @@  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;
-			info.si_addr = (void __user *)regs->pc;
-			force_sig_info(SIGFPE, &info, tsk);
+			force_sig_fault(SIGFPE, FPE_FLTINV,
+					(void __user *)regs->pc, tsk);
 		}
 
 		regs->pc = nextpc;
diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c
index 4c98b6f20e02..b8e7bb84b6b1 100644
--- a/arch/sh/mm/fault.c
+++ b/arch/sh/mm/fault.c
@@ -42,15 +42,7 @@  static void
 force_sig_info_fault(int si_signo, int si_code, unsigned long address,
 		     struct task_struct *tsk)
 {
-	siginfo_t info;
-
-	clear_siginfo(&info);
-	info.si_signo	= si_signo;
-	info.si_errno	= 0;
-	info.si_code	= si_code;
-	info.si_addr	= (void __user *)address;
-
-	force_sig_info(si_signo, &info, tsk);
+	force_sig_fault(si_signo, si_code, (void __user *)address, tsk);
 }
 
 /*