--- /dev/null
+From ff2047fb755d4415ec3c70ac799889371151796d Mon Sep 17 00:00:00 2001
+From: Jiri Slaby <jslaby@suse.cz>
+Date: Tue, 5 Jan 2021 13:02:35 +0100
+Subject: vt: drop old FONT ioctls
+
+From: Jiri Slaby <jslaby@suse.cz>
+
+commit ff2047fb755d4415ec3c70ac799889371151796d upstream.
+
+Drop support for these ioctls:
+* PIO_FONT, PIO_FONTX
+* GIO_FONT, GIO_FONTX
+* PIO_FONTRESET
+
+As was demonstrated by commit 90bfdeef83f1 (tty: make FONTX ioctl use
+the tty pointer they were actually passed), these ioctls are not used
+from userspace, as:
+1) they used to be broken (set up font on current console, not the open
+ one) and racy (before the commit above)
+2) KDFONTOP ioctl is used for years instead
+
+Note that PIO_FONTRESET is defunct on most systems as VGA_CONSOLE is set
+on them for ages. That turns on BROKEN_GRAPHICS_PROGRAMS which makes
+PIO_FONTRESET just return an error.
+
+We are removing KD_FONT_FLAG_OLD here as it was used only by these
+removed ioctls. kd.h header exists both in kernel and uapi headers, so
+we can remove the kernel one completely. Everyone includeing kd.h will
+now automatically get the uapi one.
+
+There are now unused definitions of the ioctl numbers and "struct
+consolefontdesc" in kd.h, but as it is a uapi header, I am not touching
+these.
+
+Signed-off-by: Jiri Slaby <jslaby@suse.cz>
+Link: https://lore.kernel.org/r/20210105120239.28031-8-jslaby@suse.cz
+Cc: guodaxing <guodaxing@huawei.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/tty/vt/vt.c | 39 -----------
+ drivers/tty/vt/vt_ioctl.c | 151 ----------------------------------------------
+ include/linux/kd.h | 8 --
+ 3 files changed, 3 insertions(+), 195 deletions(-)
+ delete mode 100644 include/linux/kd.h
+
+--- a/drivers/tty/vt/vt.c
++++ b/drivers/tty/vt/vt.c
+@@ -4625,16 +4625,8 @@ static int con_font_get(struct vc_data *
+
+ if (op->data && font.charcount > op->charcount)
+ rc = -ENOSPC;
+- if (!(op->flags & KD_FONT_FLAG_OLD)) {
+- if (font.width > op->width || font.height > op->height)
+- rc = -ENOSPC;
+- } else {
+- if (font.width != 8)
+- rc = -EIO;
+- else if ((op->height && font.height > op->height) ||
+- font.height > 32)
+- rc = -ENOSPC;
+- }
++ if (font.width > op->width || font.height > op->height)
++ rc = -ENOSPC;
+ if (rc)
+ goto out;
+
+@@ -4662,7 +4654,7 @@ static int con_font_set(struct vc_data *
+ return -EINVAL;
+ if (op->charcount > 512)
+ return -EINVAL;
+- if (op->width <= 0 || op->width > 32 || op->height > 32)
++ if (op->width <= 0 || op->width > 32 || !op->height || op->height > 32)
+ return -EINVAL;
+ size = (op->width+7)/8 * 32 * op->charcount;
+ if (size > max_font_size)
+@@ -4672,31 +4664,6 @@ static int con_font_set(struct vc_data *
+ if (IS_ERR(font.data))
+ return PTR_ERR(font.data);
+
+- if (!op->height) { /* Need to guess font height [compat] */
+- int h, i;
+- u8 *charmap = font.data;
+-
+- /*
+- * If from KDFONTOP ioctl, don't allow things which can be done
+- * in userland,so that we can get rid of this soon
+- */
+- if (!(op->flags & KD_FONT_FLAG_OLD)) {
+- kfree(font.data);
+- return -EINVAL;
+- }
+-
+- for (h = 32; h > 0; h--)
+- for (i = 0; i < op->charcount; i++)
+- if (charmap[32*i+h-1])
+- goto nonzero;
+-
+- kfree(font.data);
+- return -EINVAL;
+-
+- nonzero:
+- op->height = h;
+- }
+-
+ font.charcount = op->charcount;
+ font.width = op->width;
+ font.height = op->height;
+--- a/drivers/tty/vt/vt_ioctl.c
++++ b/drivers/tty/vt/vt_ioctl.c
+@@ -486,70 +486,6 @@ static int vt_k_ioctl(struct tty_struct
+ return 0;
+ }
+
+-static inline int do_fontx_ioctl(struct vc_data *vc, int cmd,
+- struct consolefontdesc __user *user_cfd,
+- struct console_font_op *op)
+-{
+- struct consolefontdesc cfdarg;
+- int i;
+-
+- if (copy_from_user(&cfdarg, user_cfd, sizeof(struct consolefontdesc)))
+- return -EFAULT;
+-
+- switch (cmd) {
+- case PIO_FONTX:
+- op->op = KD_FONT_OP_SET;
+- op->flags = KD_FONT_FLAG_OLD;
+- op->width = 8;
+- op->height = cfdarg.charheight;
+- op->charcount = cfdarg.charcount;
+- op->data = cfdarg.chardata;
+- return con_font_op(vc, op);
+-
+- case GIO_FONTX:
+- op->op = KD_FONT_OP_GET;
+- op->flags = KD_FONT_FLAG_OLD;
+- op->width = 8;
+- op->height = cfdarg.charheight;
+- op->charcount = cfdarg.charcount;
+- op->data = cfdarg.chardata;
+- i = con_font_op(vc, op);
+- if (i)
+- return i;
+- cfdarg.charheight = op->height;
+- cfdarg.charcount = op->charcount;
+- if (copy_to_user(user_cfd, &cfdarg, sizeof(struct consolefontdesc)))
+- return -EFAULT;
+- return 0;
+- }
+- return -EINVAL;
+-}
+-
+-static int vt_io_fontreset(struct vc_data *vc, struct console_font_op *op)
+-{
+- int ret;
+-
+- if (__is_defined(BROKEN_GRAPHICS_PROGRAMS)) {
+- /*
+- * With BROKEN_GRAPHICS_PROGRAMS defined, the default font is
+- * not saved.
+- */
+- return -ENOSYS;
+- }
+-
+- op->op = KD_FONT_OP_SET_DEFAULT;
+- op->data = NULL;
+- ret = con_font_op(vc, op);
+- if (ret)
+- return ret;
+-
+- console_lock();
+- con_set_default_unimap(vc);
+- console_unlock();
+-
+- return 0;
+-}
+-
+ static inline int do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud,
+ bool perm, struct vc_data *vc)
+ {
+@@ -574,29 +510,7 @@ static inline int do_unimap_ioctl(int cm
+ static int vt_io_ioctl(struct vc_data *vc, unsigned int cmd, void __user *up,
+ bool perm)
+ {
+- struct console_font_op op; /* used in multiple places here */
+-
+ switch (cmd) {
+- case PIO_FONT:
+- if (!perm)
+- return -EPERM;
+- op.op = KD_FONT_OP_SET;
+- op.flags = KD_FONT_FLAG_OLD | KD_FONT_FLAG_DONT_RECALC; /* Compatibility */
+- op.width = 8;
+- op.height = 0;
+- op.charcount = 256;
+- op.data = up;
+- return con_font_op(vc, &op);
+-
+- case GIO_FONT:
+- op.op = KD_FONT_OP_GET;
+- op.flags = KD_FONT_FLAG_OLD;
+- op.width = 8;
+- op.height = 32;
+- op.charcount = 256;
+- op.data = up;
+- return con_font_op(vc, &op);
+-
+ case PIO_CMAP:
+ if (!perm)
+ return -EPERM;
+@@ -605,20 +519,6 @@ static int vt_io_ioctl(struct vc_data *v
+ case GIO_CMAP:
+ return con_get_cmap(up);
+
+- case PIO_FONTX:
+- if (!perm)
+- return -EPERM;
+-
+- fallthrough;
+- case GIO_FONTX:
+- return do_fontx_ioctl(vc, cmd, up, &op);
+-
+- case PIO_FONTRESET:
+- if (!perm)
+- return -EPERM;
+-
+- return vt_io_fontreset(vc, &op);
+-
+ case PIO_SCRNMAP:
+ if (!perm)
+ return -EPERM;
+@@ -1099,54 +999,6 @@ void vc_SAK(struct work_struct *work)
+
+ #ifdef CONFIG_COMPAT
+
+-struct compat_consolefontdesc {
+- unsigned short charcount; /* characters in font (256 or 512) */
+- unsigned short charheight; /* scan lines per character (1-32) */
+- compat_caddr_t chardata; /* font data in expanded form */
+-};
+-
+-static inline int
+-compat_fontx_ioctl(struct vc_data *vc, int cmd,
+- struct compat_consolefontdesc __user *user_cfd,
+- int perm, struct console_font_op *op)
+-{
+- struct compat_consolefontdesc cfdarg;
+- int i;
+-
+- if (copy_from_user(&cfdarg, user_cfd, sizeof(struct compat_consolefontdesc)))
+- return -EFAULT;
+-
+- switch (cmd) {
+- case PIO_FONTX:
+- if (!perm)
+- return -EPERM;
+- op->op = KD_FONT_OP_SET;
+- op->flags = KD_FONT_FLAG_OLD;
+- op->width = 8;
+- op->height = cfdarg.charheight;
+- op->charcount = cfdarg.charcount;
+- op->data = compat_ptr(cfdarg.chardata);
+- return con_font_op(vc, op);
+-
+- case GIO_FONTX:
+- op->op = KD_FONT_OP_GET;
+- op->flags = KD_FONT_FLAG_OLD;
+- op->width = 8;
+- op->height = cfdarg.charheight;
+- op->charcount = cfdarg.charcount;
+- op->data = compat_ptr(cfdarg.chardata);
+- i = con_font_op(vc, op);
+- if (i)
+- return i;
+- cfdarg.charheight = op->height;
+- cfdarg.charcount = op->charcount;
+- if (copy_to_user(user_cfd, &cfdarg, sizeof(struct compat_consolefontdesc)))
+- return -EFAULT;
+- return 0;
+- }
+- return -EINVAL;
+-}
+-
+ struct compat_console_font_op {
+ compat_uint_t op; /* operation code KD_FONT_OP_* */
+ compat_uint_t flags; /* KD_FONT_FLAG_* */
+@@ -1223,9 +1075,6 @@ long vt_compat_ioctl(struct tty_struct *
+ /*
+ * these need special handlers for incompatible data structures
+ */
+- case PIO_FONTX:
+- case GIO_FONTX:
+- return compat_fontx_ioctl(vc, cmd, up, perm, &op);
+
+ case KDFONTOP:
+ return compat_kdfontop_ioctl(up, perm, &op, vc);
+--- a/include/linux/kd.h
++++ /dev/null
+@@ -1,8 +0,0 @@
+-/* SPDX-License-Identifier: GPL-2.0 */
+-#ifndef _LINUX_KD_H
+-#define _LINUX_KD_H
+-
+-#include <uapi/linux/kd.h>
+-
+-#define KD_FONT_FLAG_OLD 0x80000000 /* Invoked via old interface [compat] */
+-#endif /* _LINUX_KD_H */
projects / thirdparty / kernel / stable-queue.git / commitdiff
