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From: "Jiri Slaby (SUSE)" <jirislaby@kernel.org>
To: gregkh@linuxfoundation.org
Cc: linux-serial@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	"Jiri Slaby (SUSE)" <jirislaby@kernel.org>
Subject: [PATCH 25/45] tty: vt: sanitize consw::con_putcs() parameters
Date: Thu, 18 Jan 2024 08:57:36 +0100
Message-ID: <20240118075756.10541-26-jirislaby@kernel.org>
In-Reply-To: <20240118075756.10541-1-jirislaby@kernel.org>
References: <20240118075756.10541-1-jirislaby@kernel.org>
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Similar to con_putc() in the previous patch:
* make the pointer to charattr a pointer to u16, and
* make x, y, and count unsigned as they are strictly non-negative.

And again, document that hook.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
---
 drivers/video/console/dummycon.c    | 10 +++++-----
 drivers/video/console/mdacon.c      |  4 ++--
 drivers/video/console/newport_con.c |  9 +++++----
 drivers/video/console/sticon.c      |  4 ++--
 drivers/video/console/vgacon.c      |  4 ++--
 drivers/video/fbdev/core/fbcon.c    |  4 ++--
 include/linux/console.h             |  6 ++++--
 7 files changed, 22 insertions(+), 19 deletions(-)

diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c
index 1874beed0325..188d9f3e201c 100644
--- a/drivers/video/console/dummycon.c
+++ b/drivers/video/console/dummycon.c
@@ -59,10 +59,10 @@ static void dummycon_putc(struct vc_data *vc, u16 c, unsigned int y,
 	raw_notifier_call_chain(&dummycon_output_nh, 0, NULL);
 }
 
-static void dummycon_putcs(struct vc_data *vc, const unsigned short *s,
-			   int count, int ypos, int xpos)
+static void dummycon_putcs(struct vc_data *vc, const u16 *s, unsigned int count,
+			   unsigned int ypos, unsigned int xpos)
 {
-	int i;
+	unsigned int i;
 
 	if (!dummycon_putc_called) {
 		/* Ignore erases */
@@ -87,8 +87,8 @@ static int dummycon_blank(struct vc_data *vc, int blank, int mode_switch)
 #else
 static void dummycon_putc(struct vc_data *vc, u16 c, unsigned int y,
 			  unsigned int x) { }
-static void dummycon_putcs(struct vc_data *vc, const unsigned short *s,
-			   int count, int ypos, int xpos) { }
+static void dummycon_putcs(struct vc_data *vc, const u16 *s, unsigned int count,
+			   unsigned int ypos, unsigned int xpos) { }
 static int dummycon_blank(struct vc_data *vc, int blank, int mode_switch)
 {
 	return 0;
diff --git a/drivers/video/console/mdacon.c b/drivers/video/console/mdacon.c
index 01e779943c00..b8822b615b2f 100644
--- a/drivers/video/console/mdacon.c
+++ b/drivers/video/console/mdacon.c
@@ -427,8 +427,8 @@ static inline u16 *mda_addr(unsigned int x, unsigned int y)
 	return mda_vram_base + y * mda_num_columns + x;
 }
 
-static void mdacon_putcs(struct vc_data *c, const unsigned short *s,
-		         int count, int y, int x)
+static void mdacon_putcs(struct vc_data *c, const u16 *s, unsigned int count,
+			 unsigned int y, unsigned int x)
 {
 	u16 *dest = mda_addr(x, y);
 
diff --git a/drivers/video/console/newport_con.c b/drivers/video/console/newport_con.c
index 9b5c0118873e..5e65ee0b7c07 100644
--- a/drivers/video/console/newport_con.c
+++ b/drivers/video/console/newport_con.c
@@ -396,12 +396,13 @@ static void newport_putc(struct vc_data *vc, u16 charattr, unsigned int ypos,
 	RENDER(npregs, p);
 }
 
-static void newport_putcs(struct vc_data *vc, const unsigned short *s,
-			  int count, int ypos, int xpos)
+static void newport_putcs(struct vc_data *vc, const u16 *s,
+			  unsigned int count, unsigned int ypos,
+			  unsigned int xpos)
 {
-	int i;
-	int charattr;
 	unsigned char *p;
+	unsigned int i;
+	u16 charattr;
 
 	charattr = (scr_readw(s) >> 8) & 0xff;
 
diff --git a/drivers/video/console/sticon.c b/drivers/video/console/sticon.c
index 2f87b5909d0d..906da1fde7c8 100644
--- a/drivers/video/console/sticon.c
+++ b/drivers/video/console/sticon.c
@@ -71,8 +71,8 @@ static const char *sticon_startup(void)
     return "STI console";
 }
 
-static void sticon_putcs(struct vc_data *conp, const unsigned short *s,
-			 int count, int ypos, int xpos)
+static void sticon_putcs(struct vc_data *conp, const u16 *s, unsigned int count,
+			 unsigned int ypos, unsigned int xpos)
 {
     if (vga_is_gfx || console_blanked)
 	    return;
diff --git a/drivers/video/console/vgacon.c b/drivers/video/console/vgacon.c
index 2cb75be74c38..558076462b0d 100644
--- a/drivers/video/console/vgacon.c
+++ b/drivers/video/console/vgacon.c
@@ -1193,8 +1193,8 @@ static bool vgacon_scroll(struct vc_data *c, unsigned int t, unsigned int b,
 
 static void vgacon_clear(struct vc_data *vc, unsigned int sy, unsigned int sx,
 			 unsigned int width) { }
-static void vgacon_putcs(struct vc_data *vc, const unsigned short *s,
-			 int count, int ypos, int xpos) { }
+static void vgacon_putcs(struct vc_data *vc, const u16 *s, unsigned int count,
+			 unsigned int ypos, unsigned int xpos) { }
 
 const struct consw vga_con = {
 	.owner = THIS_MODULE,
diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
index 38de0f8723aa..7a7b2ac0d7a9 100644
--- a/drivers/video/fbdev/core/fbcon.c
+++ b/drivers/video/fbdev/core/fbcon.c
@@ -1279,8 +1279,8 @@ static void fbcon_clear(struct vc_data *vc, unsigned int sy, unsigned int sx,
 	__fbcon_clear(vc, sy, sx, 1, width);
 }
 
-static void fbcon_putcs(struct vc_data *vc, const unsigned short *s,
-			int count, int ypos, int xpos)
+static void fbcon_putcs(struct vc_data *vc, const u16 *s, unsigned int count,
+			unsigned int ypos, unsigned int xpos)
 {
 	struct fb_info *info = fbcon_info_from_console(vc->vc_num);
 	struct fbcon_display *p = &fb_display[vc->vc_num];
diff --git a/include/linux/console.h b/include/linux/console.h
index 92d57e5b3009..82d55764a66f 100644
--- a/include/linux/console.h
+++ b/include/linux/console.h
@@ -41,6 +41,7 @@ enum vc_intensity;
  * @con_clear:  erase @count characters at [@x, @y] on @vc. @count >= 1.
  * @con_putc:   emit one character with attributes @ca to [@x, @y] on @vc.
  *		(optional -- @con_putcs would be called instead)
+ * @con_putcs:  emit @count characters with attributes @s to [@x, @y] on @vc.
  * @con_scroll: move lines from @top to @bottom in direction @dir by @lines.
  *		Return true if no generic handling should be done.
  *		Invoked by csi_M and printing to the console.
@@ -57,8 +58,9 @@ struct consw {
 			     unsigned int x, unsigned int count);
 	void	(*con_putc)(struct vc_data *vc, u16 ca, unsigned int y,
 			    unsigned int x);
-	void	(*con_putcs)(struct vc_data *vc, const unsigned short *s,
-			int count, int ypos, int xpos);
+	void	(*con_putcs)(struct vc_data *vc, const u16 *s,
+			     unsigned int count, unsigned int ypos,
+			     unsigned int xpos);
 	void	(*con_cursor)(struct vc_data *vc, int mode);
 	bool	(*con_scroll)(struct vc_data *vc, unsigned int top,
 			unsigned int bottom, enum con_scroll dir,
-- 
2.43.0