Commit 2fe16088 authored by Jiri Slaby (SUSE)'s avatar Jiri Slaby (SUSE) Committed by Greg Kroah-Hartman
Browse files

tty/vt: use guard()s in con_font_set/get() and con_{set,get}_unimap() 

Having all the new guards, use them in the 8250_rsa code. This improves
readability, makes error handling easier, and marks locked portions of
code explicit.

The new __free()-annotated declarations are moved to the allocation points
as is preferred:
https://lore.kernel.org/all/CAHk-=wjvh_LUpa=864joG2JJXs3+viO-kLzLidR2JLyMr4MNwA@mail.gmail.com/



Except font_data in con_font_get(). The scope in there would not match
the expected lifetime. But the declaration is moved closer.

Signed-off-by: default avatar"Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20250814072456.182853-15-jirislaby@kernel.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 54faf047

drivers/tty/vt/consolemap.c

+38 −46
Original line number Diff line number Diff line
@@ -637,32 +637,28 @@ static struct uni_pagedict *con_unshare_unimap(struct vc_data *vc, 


int con_set_unimap(struct vc_data *vc, ushort ct, struct unipair __user *list)

{

	int err = 0, err1;

	struct uni_pagedict *dict;

	struct unipair *unilist, *plist;

	struct unipair *plist;

	int err = 0;



	if (!ct)

		return 0;



	unilist = vmemdup_array_user(list, ct, sizeof(*unilist));

	struct unipair *unilist __free(kvfree) = vmemdup_array_user(list, ct, sizeof(*unilist));

	if (IS_ERR(unilist))

		return PTR_ERR(unilist);



	console_lock();

	guard(console_lock)();



	/* Save original vc_unipagdir_loc in case we allocate a new one */

	dict = *vc->uni_pagedict_loc;

	if (!dict) {

		err = -EINVAL;

		goto out_unlock;

	}

	if (!dict)

		return -EINVAL;



	if (dict->refcount > 1) {

		dict = con_unshare_unimap(vc, dict);

		if (IS_ERR(dict)) {

			err = PTR_ERR(dict);

			goto out_unlock;

		}

		if (IS_ERR(dict))

			return PTR_ERR(dict);

	} else if (dict == dflt) {

		dflt = NULL;

	}
@@ -671,7 +667,7 @@ int con_set_unimap(struct vc_data *vc, ushort ct, struct unipair __user *list) 
	 * Insert user specified unicode pairs into new table.

	 */

	for (plist = unilist; ct; ct--, plist++) {

		err1 = con_insert_unipair(dict, plist->unicode, plist->fontpos);

		int err1 = con_insert_unipair(dict, plist->unicode, plist->fontpos);

		if (err1)

			err = err1;

	}
@@ -680,15 +676,12 @@ int con_set_unimap(struct vc_data *vc, ushort ct, struct unipair __user *list) 
	 * Merge with fontmaps of any other virtual consoles.

	 */

	if (con_unify_unimap(vc, dict))

		goto out_unlock;

		return err;



	for (enum translation_map m = FIRST_MAP; m <= LAST_MAP; m++)

		set_inverse_transl(vc, dict, m);

	set_inverse_trans_unicode(dict);



out_unlock:

	console_unlock();

	kvfree(unilist);

	return err;

}
@@ -787,20 +780,17 @@ int con_get_unimap(struct vc_data *vc, ushort ct, ushort __user *uct, 
{

	ushort ect;

	struct uni_pagedict *dict;

	struct unipair *unilist;

	unsigned int d, r, g;

	int ret = 0;



	unilist = kvmalloc_array(ct, sizeof(*unilist), GFP_KERNEL);

	struct unipair *unilist __free(kvfree) = kvmalloc_array(ct, sizeof(*unilist), GFP_KERNEL);

	if (!unilist)

		return -ENOMEM;



	console_lock();



	scoped_guard(console_lock) {

		ect = 0;

		dict = *vc->uni_pagedict_loc;

		if (!dict)

		goto unlock;

			break;



		for (d = 0; d < UNI_DIRS; d++) {

			u16 **dir = dict->uni_pgdir[d];
@@ -823,14 +813,16 @@ int con_get_unimap(struct vc_data *vc, ushort ct, ushort __user *uct, 
				}

			}

		}

unlock:

	console_unlock();

	}



	if (copy_to_user(list, unilist, min(ect, ct) * sizeof(*unilist)))

		ret = -EFAULT;

		return -EFAULT;

	if (put_user(ect, uct))

		ret = -EFAULT;

	kvfree(unilist);

	return ret ? ret : (ect <= ct) ? 0 : -ENOMEM;

		return -EFAULT;

	if (ect > ct)

		return -ENOMEM;



	return 0;

}



/*

drivers/tty/vt/vt.c

+40 −49
Original line number Diff line number Diff line
@@ -4801,57 +4801,51 @@ void reset_palette(struct vc_data *vc) 
static int con_font_get(struct vc_data *vc, struct console_font_op *op)

{

	struct console_font font;

	int rc = -EINVAL;

	int c;

	unsigned int vpitch = op->op == KD_FONT_OP_GET_TALL ? op->height : 32;



	if (vpitch > max_font_height)

		return -EINVAL;



	void *font_data __free(kvfree) = NULL;

	if (op->data) {

		font.data = kvzalloc(max_font_size, GFP_KERNEL);

		font.data = font_data = kvzalloc(max_font_size, GFP_KERNEL);

		if (!font.data)

			return -ENOMEM;

	} else

		font.data = NULL;



	console_lock();

	scoped_guard(console_lock) {

		if (vc->vc_mode != KD_TEXT)

		rc = -EINVAL;

	else if (vc->vc_sw->con_font_get)

		rc = vc->vc_sw->con_font_get(vc, &font, vpitch);

	else

		rc = -ENOSYS;

	console_unlock();

			return -EINVAL;

		if (!vc->vc_sw->con_font_get)

			return -ENOSYS;



	if (rc)

		goto out;

		int ret = vc->vc_sw->con_font_get(vc, &font, vpitch);

		if (ret)

			return ret;

	}



	c = (font.width+7)/8 * vpitch * font.charcount;



	if (op->data && font.charcount > op->charcount)

		rc = -ENOSPC;

		return -ENOSPC;

	if (font.width > op->width || font.height > op->height)

		rc = -ENOSPC;

	if (rc)

		goto out;

		return -ENOSPC;



	op->height = font.height;

	op->width = font.width;

	op->charcount = font.charcount;



	if (op->data && copy_to_user(op->data, font.data, c))

		rc = -EFAULT;

		return -EFAULT;



out:

	kvfree(font.data);

	return rc;

	return 0;

}



static int con_font_set(struct vc_data *vc, const struct console_font_op *op)

{

	struct console_font font;

	int rc = -EINVAL;

	int size;

	unsigned int vpitch = op->op == KD_FONT_OP_SET_TALL ? op->height : 32;
@@ -4870,7 +4864,7 @@ static int con_font_set(struct vc_data *vc, const struct console_font_op *op) 
	if (size > max_font_size)

		return -ENOSPC;



	font.data = memdup_user(op->data, size);

	void *font_data __free(kfree) = font.data = memdup_user(op->data, size);

	if (IS_ERR(font.data))

		return PTR_ERR(font.data);
@@ -4878,18 +4872,17 @@ static int con_font_set(struct vc_data *vc, const struct console_font_op *op) 
	font.width = op->width;

	font.height = op->height;



	console_lock();

	guard(console_lock)();



	if (vc->vc_mode != KD_TEXT)

		rc = -EINVAL;

	else if (vc->vc_sw->con_font_set) {

		return -EINVAL;

	if (!vc->vc_sw->con_font_set)

		return -ENOSYS;



	if (vc_is_sel(vc))

		clear_selection();

		rc = vc->vc_sw->con_font_set(vc, &font, vpitch, op->flags);

	} else

		rc = -ENOSYS;

	console_unlock();

	kfree(font.data);

	return rc;



	return vc->vc_sw->con_font_set(vc, &font, vpitch, op->flags);

}



static int con_font_default(struct vc_data *vc, struct console_font_op *op)
@@ -4897,8 +4890,6 @@ static int con_font_default(struct vc_data *vc, struct console_font_op *op) 
	struct console_font font = {.width = op->width, .height = op->height};

	char name[MAX_FONT_NAME];

	char *s = name;

	int rc;





	if (!op->data)

		s = NULL;
@@ -4907,23 +4898,23 @@ static int con_font_default(struct vc_data *vc, struct console_font_op *op) 
	else

		name[MAX_FONT_NAME - 1] = 0;



	console_lock();

	if (vc->vc_mode != KD_TEXT) {

		console_unlock();

	scoped_guard(console_lock) {

		if (vc->vc_mode != KD_TEXT)

			return -EINVAL;

	}

	if (vc->vc_sw->con_font_default) {

		if (!vc->vc_sw->con_font_default)

			return -ENOSYS;



		if (vc_is_sel(vc))

			clear_selection();

		rc = vc->vc_sw->con_font_default(vc, &font, s);

	} else

		rc = -ENOSYS;

	console_unlock();

	if (!rc) {

		int ret = vc->vc_sw->con_font_default(vc, &font, s);

		if (ret)

			return ret;

	}



	op->width = font.width;

	op->height = font.height;

	}

	return rc;



	return 0;

}



int con_font_op(struct vc_data *vc, struct console_font_op *op)