Re: [PATCH 1/2] security/selinux: fix /proc/sys/ labeling

[ebiederm@xmission.com (Eric W. Biederman)]

Lucian Adrian Grijincu <lucian.grijincu@gmail.com> writes:

> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> index e276eb4..5231b95 100644
> --- a/security/selinux/hooks.c
> +++ b/security/selinux/hooks.c
> @@ -43,7 +43,6 @@
>  #include <linux/fdtable.h>
>  #include <linux/namei.h>
>  #include <linux/mount.h>
> -#include <linux/proc_fs.h>
>  #include <linux/netfilter_ipv4.h>
>  #include <linux/netfilter_ipv6.h>
>  #include <linux/tty.h>
> @@ -70,7 +69,6 @@
>  #include <net/ipv6.h>
>  #include <linux/hugetlb.h>
>  #include <linux/personality.h>
> -#include <linux/sysctl.h>
>  #include <linux/audit.h>
>  #include <linux/string.h>
>  #include <linux/selinux.h>
> @@ -1120,39 +1118,35 @@ static inline u16 socket_type_to_security_class(int family, int type, int protoc
>  }
>  
>  #ifdef CONFIG_PROC_FS
> -static int selinux_proc_get_sid(struct proc_dir_entry *de,
> +static int selinux_proc_get_sid(struct dentry *dentry,
>  				u16 tclass,
>  				u32 *sid)
>  {
> -	int buflen, rc;
> -	char *buffer, *path, *end;
> +	int rc;
> +	char *buffer, *path;
>  
>  	buffer = (char *)__get_free_page(GFP_KERNEL);
>  	if (!buffer)
>  		return -ENOMEM;
>  
> -	buflen = PAGE_SIZE;
> -	end = buffer+buflen;
> -	*--end = '\0';
> -	buflen--;
> -	path = end-1;
> -	*path = '/';
> -	while (de && de != de->parent) {
> -		buflen -= de->namelen + 1;
> -		if (buflen < 0)
> -			break;
> -		end -= de->namelen;
> -		memcpy(end, de->name, de->namelen);
> -		*--end = '/';
> -		path = end;
> -		de = de->parent;
> +	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);

What kernel has a dentry_path_raw?  Perhaps you mean __dentry_path?

> +	if (IS_ERR(path))
> +		rc = PTR_ERR(path);
> +	else {
> +		/* each process gets a /proc/PID/ entry. Strip off the
> +		 * PID part to get a valid selinux labeling.
> +		 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
> +		while (path[1] >= '0' && path[1] <= '9') {
> +			path[1] = '/';
> +			path++;
> +		}
> +		rc = security_genfs_sid("proc", path, tclass, sid);
>  	}
> -	rc = security_genfs_sid("proc", path, tclass, sid);
>  	free_page((unsigned long)buffer);
>  	return rc;
>  }
>  #else

Eric