24 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			24 lines
		
	
	
		
			1.2 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| What:		/sys/fs/selinux/checkreqprot
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| Date:		April 2005 (predates git)
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| KernelVersion:	2.6.12-rc2 (predates git)
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| Contact:	selinux@vger.kernel.org
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| Description:
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| 
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| 	The selinuxfs "checkreqprot" node allows SELinux to be configured
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| 	to check the protection requested by userspace for mmap/mprotect
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| 	calls instead of the actual protection applied by the kernel.
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| 	This was a compatibility mechanism for legacy userspace and
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| 	for the READ_IMPLIES_EXEC personality flag.  However, if set to
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| 	1, it weakens security by allowing mappings to be made executable
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| 	without authorization by policy.  The default value of checkreqprot
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| 	at boot was changed starting in Linux v4.4 to 0 (i.e. check the
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| 	actual protection), and Android and Linux distributions have been
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| 	explicitly writing a "0" to /sys/fs/selinux/checkreqprot during
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| 	initialization for some time.  Support for setting checkreqprot to 1
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| 	will be	removed no sooner than June 2021, at which point the kernel
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| 	will always cease using checkreqprot internally and will always
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| 	check the actual protections being applied upon mmap/mprotect calls.
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| 	The checkreqprot selinuxfs node will remain for backward compatibility
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| 	but will discard writes of the "0" value and will reject writes of the
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| 	"1" value when this mechanism is removed.
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