forked from mirrors/linux
		
	Remove unnecessary ERR_PTR()/PTR_ERR() cast in proc_setup_thread_self(). Link: http://lkml.kernel.org/r/20190124030150.8472-2-cgxu519@gmx.com Signed-off-by: Chengguang Xu <cgxu519@gmx.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			73 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			73 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0
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#include <linux/cache.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/pid_namespace.h>
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#include "internal.h"
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/*
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 * /proc/thread_self:
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 */
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static const char *proc_thread_self_get_link(struct dentry *dentry,
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					     struct inode *inode,
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					     struct delayed_call *done)
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{
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	struct pid_namespace *ns = proc_pid_ns(inode);
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	pid_t tgid = task_tgid_nr_ns(current, ns);
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	pid_t pid = task_pid_nr_ns(current, ns);
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	char *name;
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	if (!pid)
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		return ERR_PTR(-ENOENT);
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	name = kmalloc(10 + 6 + 10 + 1, dentry ? GFP_KERNEL : GFP_ATOMIC);
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	if (unlikely(!name))
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		return dentry ? ERR_PTR(-ENOMEM) : ERR_PTR(-ECHILD);
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	sprintf(name, "%u/task/%u", tgid, pid);
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	set_delayed_call(done, kfree_link, name);
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	return name;
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}
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static const struct inode_operations proc_thread_self_inode_operations = {
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	.get_link	= proc_thread_self_get_link,
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};
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static unsigned thread_self_inum __ro_after_init;
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int proc_setup_thread_self(struct super_block *s)
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{
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	struct inode *root_inode = d_inode(s->s_root);
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	struct pid_namespace *ns = proc_pid_ns(root_inode);
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	struct dentry *thread_self;
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	int ret = -ENOMEM;
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	inode_lock(root_inode);
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	thread_self = d_alloc_name(s->s_root, "thread-self");
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	if (thread_self) {
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		struct inode *inode = new_inode_pseudo(s);
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		if (inode) {
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			inode->i_ino = thread_self_inum;
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			inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
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			inode->i_mode = S_IFLNK | S_IRWXUGO;
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			inode->i_uid = GLOBAL_ROOT_UID;
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			inode->i_gid = GLOBAL_ROOT_GID;
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			inode->i_op = &proc_thread_self_inode_operations;
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			d_add(thread_self, inode);
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			ret = 0;
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		} else {
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			dput(thread_self);
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		}
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	}
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	inode_unlock(root_inode);
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	if (ret)
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		pr_err("proc_fill_super: can't allocate /proc/thread_self\n");
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	else
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		ns->proc_thread_self = thread_self;
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	return ret;
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}
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void __init proc_thread_self_init(void)
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{
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	proc_alloc_inum(&thread_self_inum);
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}
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