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			36 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
			
		
		
	
	
			36 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
| From d52bcb0a807dde87057f330dbe95aa6d221a4b85 Mon Sep 17 00:00:00 2001
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| From: =?utf-8?q?Arve=20Hj=C3=B8nnev=C3=A5g?= <arve@android.com>
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| Date: Mon, 9 Apr 2007 17:13:02 +0700
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| Subject: [PATCH 060/134] [ARM] Add code to prevent system calls from being restarted muliple times before returning from the kernel.
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| 
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| Fixes crashes with thumb syscalls.
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| ---
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|  arch/arm/kernel/signal.c |    9 +++++++++
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|  1 files changed, 9 insertions(+), 0 deletions(-)
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| 
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| --- a/arch/arm/kernel/signal.c
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| +++ b/arch/arm/kernel/signal.c
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| @@ -499,6 +499,14 @@ setup_rt_frame(int usig, struct k_sigact
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|  
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|  static inline void restart_syscall(struct pt_regs *regs)
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|  {
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| +	if (regs->ARM_ORIG_r0 == -ERESTARTNOHAND ||
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| +	    regs->ARM_ORIG_r0 == -ERESTARTSYS ||
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| +	    regs->ARM_ORIG_r0 == -ERESTARTNOINTR ||
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| +	    regs->ARM_ORIG_r0 == -ERESTART_RESTARTBLOCK) {
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| +		/* the syscall cannot be safely restarted, return -EINTR instead */
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| +		regs->ARM_r0 = -EINTR;
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| +		return;
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| +	}
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|  	regs->ARM_r0 = regs->ARM_ORIG_r0;
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|  	regs->ARM_pc -= thumb_mode(regs) ? 2 : 4;
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|  }
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| @@ -631,6 +639,7 @@ static void do_signal(struct pt_regs *re
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|  	 */
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|  	if (syscall) {
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|  		if (regs->ARM_r0 == -ERESTART_RESTARTBLOCK) {
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| +			regs->ARM_r0 = -EAGAIN; /* prevent multiple restarts */
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|  			if (thumb_mode(regs)) {
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|  				regs->ARM_r7 = __NR_restart_syscall - __NR_SYSCALL_BASE;
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|  				regs->ARM_pc -= 2;
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