Given the following code containing errors, provide Common Weakness Enumeration (CWE) identifiers and corresponding messages in JSON format. Each identified weakness should have a unique entry in the JSON array.
    Code: int vc_allocate(unsigned int currcons)	/* return 0 on success */
{
	struct vt_notifier_param param;
	struct vc_data *vc;

	WARN_CONSOLE_UNLOCKED();

	if (currcons >= MAX_NR_CONSOLES)
		return -ENXIO;

	if (vc_cons[currcons].d)
		return 0;

	/* due to the granularity of kmalloc, we waste some memory here */
	/* the alloc is done in two steps, to optimize the common situation
	   of a 25x80 console (structsize=216, screenbuf_size=4000) */
	/* although the numbers above are not valid since long ago, the
	   point is still up-to-date and the comment still has its value
	   even if only as a historical artifact.  --mj, July 1998 */
	param.vc = vc = kzalloc(sizeof(struct vc_data), GFP_KERNEL);
	if (!vc)
		return -ENOMEM;

	vc_cons[currcons].d = vc;
	tty_port_init(&vc->port);
	INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);

	visual_init(vc, currcons, 1);

	if (!*vc->vc_uni_pagedir_loc)
		con_set_default_unimap(vc);

	vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL);
	if (!vc->vc_screenbuf)
		goto err_free;

	/* If no drivers have overridden us and the user didn't pass a
	   boot option, default to displaying the cursor */
	if (global_cursor_default == -1)
		global_cursor_default = 1;

	vc_init(vc, vc->vc_rows, vc->vc_cols, 1);
	vcs_make_sysfs(currcons);
	atomic_notifier_call_chain(&vt_notifier_list, VT_ALLOCATE, &param);

	return 0;
err_free:
	visual_deinit(vc);
	kfree(vc);
	vc_cons[currcons].d = NULL;
	return -ENOMEM;
} ; Sample JSON Format Confermily Expected output: "examples" => "cwe": "xxx"; "message": "xxx"
    
 'cwe': ['CWE-416', 'CWE-362'], 'message': 'vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console

The VT_DISALLOCATE ioctl can free a virtual console while tty_release()
is still running, causing a use-after-free in con_shutdown().  This
occurs because VT_DISALLOCATE considers a virtual console's
'struct vc_data' to be unused as soon as the corresponding tty's
refcount hits 0.  But actually it may be still being closed.

Fix this by making vc_data be reference-counted via the embedded
'struct tty_port'.  A newly allocated virtual console has refcount 1.
Opening it for the first time increments the refcount to 2.  Closing it
for the last time decrements the refcount (in tty_operations::cleanup()
so that it happens late enough), as does VT_DISALLOCATE.

Reproducer:
	#include <fcntl.h>
	#include <linux/vt.h>
	#include <sys/ioctl.h>
	#include <unistd.h>

	int main()
	{
		if (fork()) {
			for (;;)
				close(open("/dev/tty5", O_RDWR));
		} else {
			int fd = open("/dev/tty10", O_RDWR);

			for (;;)
				ioctl(fd, VT_DISALLOCATE, 5);
		}
	}

KASAN report:
	BUG: KASAN: use-after-free in con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278
	Write of size 8 at addr ffff88806a4ec108 by task syz_vt/129

	CPU: 0 PID: 129 Comm: syz_vt Not tainted 5.6.0-rc2 #11
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014
	Call Trace:
	 [...]
	 con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278
	 release_tty+0xa8/0x410 drivers/tty/tty_io.c:1514
	 tty_release_struct+0x34/0x50 drivers/tty/tty_io.c:1629
	 tty_release+0x984/0xed0 drivers/tty/tty_io.c:1789
	 [...]

	Allocated by task 129:
	 [...]
	 kzalloc include/linux/slab.h:669 [inline]
	 vc_allocate drivers/tty/vt/vt.c:1085 [inline]
	 vc_allocate+0x1ac/0x680 drivers/tty/vt/vt.c:1066
	 con_install+0x4d/0x3f0 drivers/tty/vt/vt.c:3229
	 tty_driver_install_tty drivers/tty/tty_io.c:1228 [inline]
	 tty_init_dev+0x94/0x350 drivers/tty/tty_io.c:1341
	 tty_open_by_driver drivers/tty/tty_io.c:1987 [inline]
	 tty_open+0x3ca/0xb30 drivers/tty/tty_io.c:2035
	 [...]

	Freed by task 130:
	 [...]
	 kfree+0xbf/0x1e0 mm/slab.c:3757
	 vt_disallocate drivers/tty/vt/vt_ioctl.c:300 [inline]
	 vt_ioctl+0x16dc/0x1e30 drivers/tty/vt/vt_ioctl.c:818
	 tty_ioctl+0x9db/0x11b0 drivers/tty/tty_io.c:2660
	 [...]

Fixes: 4001d7b7fc27 ("vt: push down the tty lock so we can see what is left to tackle")
Cc: <stable@vger.kernel.org> # v3.4+
Reported-by: syzbot+522643ab5729b0421998@syzkaller.appspotmail.com
Acked-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200322034305.210082-2-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>'