From: Alan Cox <alan@linux.intel.com>
Date: Mon, 12 Jan 2015 11:05:53 +0000 (+0000)
Subject: ioctl: implement the superuser bit
X-Git-Url: https://git.ndcode.org/public/gitweb.cgi?a=commitdiff_plain;h=f87907537f9caed21520ff95971739e853861cda;p=FUZIX.git

ioctl: implement the superuser bit

We need to check this at the syscall level so we can allow it to be invoked
internally without security restrictions but directly with
---

diff --git a/Kernel/syscall_fs.c b/Kernel/syscall_fs.c
index 6ce0d2e2..3a175cae 100644
--- a/Kernel/syscall_fs.c
+++ b/Kernel/syscall_fs.c
@@ -257,23 +257,26 @@ int16_t _ioctl(void)
 	uint16_t dev;
 
 	if ((ino = getinode(fd)) == NULLINODE)
-		return (-1);
+		return -1;
 
 	if (!(isdevice(ino))) {
 		udata.u_error = ENOTTY;
-		return (-1);
+		return -1;
 	}
 
+	if ((request & IOCTL_SUPER) && esuper())
+	        return -1;
+
 	if (!(getperm(ino) & OTH_WR)) {
 		udata.u_error = EPERM;
-		return (-1);
+		return -1;
 	}
 
 	dev = ino->c_node.i_addr[0];
 
 	/* top bit of request is reserved for kernel originated magic */
 	if (d_ioctl(dev, request & 0x7FFF, data))
-		return (-1);
+		return -1;
 	return (0);
 }