[PATCH RESEND] selinux: use isdigit() in selinux_genfs_get_sid()

[Thorsten Blum <blum@kernel.org>]

Use isdigit() to replace the open-coded implementation.

Acked-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Thorsten Blum <blum@kernel.org>
---
 security/selinux/hooks.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 9950f89dfaa2..a6ef4083e671 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -31,6 +31,7 @@
 #include <linux/lsm_hooks.h>
 #include <linux/xattr.h>
 #include <linux/capability.h>
+#include <linux/ctype.h>
 #include <linux/unistd.h>
 #include <linux/mm.h>
 #include <linux/mman.h>
@@ -1357,7 +1358,7 @@ static int selinux_genfs_get_sid(struct dentry *dentry,
 			/* 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') {
+			while (isdigit(path[1])) {
 				path[1] = '/';
 				path++;
 			}