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	 11a921909f
			
		
	
	
		11a921909f
		
	
	
	
	
		
			
			This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) Remove the sentinel from ctl_table arrays. Reduce by one the values used to compare the size of the adjusted arrays. Signed-off-by: Joel Granados <j.granados@samsung.com>
		
			
				
	
	
		
			53 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			53 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0 */
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| #ifndef LINUX_PID_SYSCTL_H
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| #define LINUX_PID_SYSCTL_H
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| 
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| #include <linux/pid_namespace.h>
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| 
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| #if defined(CONFIG_SYSCTL) && defined(CONFIG_MEMFD_CREATE)
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| static int pid_mfd_noexec_dointvec_minmax(struct ctl_table *table,
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| 	int write, void *buf, size_t *lenp, loff_t *ppos)
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| {
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| 	struct pid_namespace *ns = task_active_pid_ns(current);
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| 	struct ctl_table table_copy;
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| 	int err, scope, parent_scope;
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| 
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| 	if (write && !ns_capable(ns->user_ns, CAP_SYS_ADMIN))
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| 		return -EPERM;
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| 
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| 	table_copy = *table;
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| 
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| 	/* You cannot set a lower enforcement value than your parent. */
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| 	parent_scope = pidns_memfd_noexec_scope(ns->parent);
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| 	/* Equivalent to pidns_memfd_noexec_scope(ns). */
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| 	scope = max(READ_ONCE(ns->memfd_noexec_scope), parent_scope);
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| 
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| 	table_copy.data = &scope;
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| 	table_copy.extra1 = &parent_scope;
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| 
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| 	err = proc_dointvec_minmax(&table_copy, write, buf, lenp, ppos);
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| 	if (!err && write)
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| 		WRITE_ONCE(ns->memfd_noexec_scope, scope);
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| 	return err;
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| }
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| 
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| static struct ctl_table pid_ns_ctl_table_vm[] = {
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| 	{
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| 		.procname	= "memfd_noexec",
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| 		.data		= &init_pid_ns.memfd_noexec_scope,
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| 		.maxlen		= sizeof(init_pid_ns.memfd_noexec_scope),
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| 		.mode		= 0644,
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| 		.proc_handler	= pid_mfd_noexec_dointvec_minmax,
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| 		.extra1		= SYSCTL_ZERO,
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| 		.extra2		= SYSCTL_TWO,
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| 	},
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| };
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| static inline void register_pid_ns_sysctl_table_vm(void)
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| {
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| 	register_sysctl("vm", pid_ns_ctl_table_vm);
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| }
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| #else
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| static inline void register_pid_ns_sysctl_table_vm(void) {}
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| #endif
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| 
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| #endif /* LINUX_PID_SYSCTL_H */
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