This expands the no-op dummy functions into full prototypes to avoid indirect call mismatches when running under Control Flow Integrity checking, like with Clang's -fsanitize=cfi.
Co-Developed-by: Sami Tolvanen samitolvanen@google.com Signed-off-by: Sami Tolvanen samitolvanen@google.com Signed-off-by: Kees Cook keescook@chromium.org --- drivers/usb/misc/sisusbvga/sisusb_con.c | 67 +++++++++++++++++++++++++------- drivers/video/console/dummycon.c | 69 +++++++++++++++++++++++++-------- drivers/video/console/newport_con.c | 10 ++--- drivers/video/console/vgacon.c | 20 +++++----- drivers/video/fbdev/core/fbcon.c | 3 +- 5 files changed, 121 insertions(+), 48 deletions(-)
diff --git a/drivers/usb/misc/sisusbvga/sisusb_con.c b/drivers/usb/misc/sisusbvga/sisusb_con.c index 998df891bdde..a0d6e0af957c 100644 --- a/drivers/usb/misc/sisusbvga/sisusb_con.c +++ b/drivers/usb/misc/sisusbvga/sisusb_con.c @@ -1217,7 +1217,7 @@ sisusbcon_do_font_op(struct sisusb_usb_data *sisusb, int set, int slot, /* Interface routine */ static int sisusbcon_font_set(struct vc_data *c, struct console_font *font, - unsigned flags) + unsigned int flags) { struct sisusb_usb_data *sisusb; unsigned charcount = font->charcount; @@ -1338,28 +1338,65 @@ static void sisusbdummycon_init(struct vc_data *vc, int init) vc_resize(vc, 80, 25); }
-static int sisusbdummycon_dummy(void) +static void sisusbdummycon_deinit(struct vc_data *vc) { } +static void sisusbdummycon_clear(struct vc_data *vc, int sy, int sx, + int height, int width) { } +static void sisusbdummycon_putc(struct vc_data *vc, int c, int ypos, + int xpos) { } +static void sisusbdummycon_putcs(struct vc_data *vc, const unsigned short *s, + int count, int ypos, int xpos) { } +static void sisusbdummycon_cursor(struct vc_data *vc, int mode) { } + +static bool sisusbdummycon_scroll(struct vc_data *vc, unsigned int top, + unsigned int bottom, enum con_scroll dir, + unsigned int lines) { - return 0; + return false; }
-#define SISUSBCONDUMMY (void *)sisusbdummycon_dummy +static int sisusbdummycon_switch(struct vc_data *vc) +{ + return 0; +} + +static int sisusbdummycon_blank(struct vc_data *vc, int blank, int mode_switch) +{ + return 0; +} + +static int sisusbdummycon_font_set(struct vc_data *vc, + struct console_font *font, + unsigned int flags) +{ + return 0; +} + +static int sisusbdummycon_font_default(struct vc_data *vc, + struct console_font *font, char *name) +{ + return 0; +} + +static int sisusbdummycon_font_copy(struct vc_data *vc, int con) +{ + return 0; +}
static const struct consw sisusb_dummy_con = { .owner = THIS_MODULE, .con_startup = sisusbdummycon_startup, .con_init = sisusbdummycon_init, - .con_deinit = SISUSBCONDUMMY, - .con_clear = SISUSBCONDUMMY, - .con_putc = SISUSBCONDUMMY, - .con_putcs = SISUSBCONDUMMY, - .con_cursor = SISUSBCONDUMMY, - .con_scroll = SISUSBCONDUMMY, - .con_switch = SISUSBCONDUMMY, - .con_blank = SISUSBCONDUMMY, - .con_font_set = SISUSBCONDUMMY, - .con_font_default = SISUSBCONDUMMY, - .con_font_copy = SISUSBCONDUMMY, + .con_deinit = sisusbdummycon_deinit, + .con_clear = sisusbdummycon_clear, + .con_putc = sisusbdummycon_putc, + .con_putcs = sisusbdummycon_putcs, + .con_cursor = sisusbdummycon_cursor, + .con_scroll = sisusbdummycon_scroll, + .con_switch = sisusbdummycon_switch, + .con_blank = sisusbdummycon_blank, + .con_font_set = sisusbdummycon_font_set, + .con_font_default = sisusbdummycon_font_default, + .con_font_copy = sisusbdummycon_font_copy, };
int diff --git a/drivers/video/console/dummycon.c b/drivers/video/console/dummycon.c index b90ef96e43d6..f2eafe2ed980 100644 --- a/drivers/video/console/dummycon.c +++ b/drivers/video/console/dummycon.c @@ -41,12 +41,47 @@ static void dummycon_init(struct vc_data *vc, int init) vc_resize(vc, DUMMY_COLUMNS, DUMMY_ROWS); }
-static int dummycon_dummy(void) +static void dummycon_deinit(struct vc_data *vc) { } +static void dummycon_clear(struct vc_data *vc, int sy, int sx, int height, + int width) { } +static void dummycon_putc(struct vc_data *vc, int c, int ypos, int xpos) { } +static void dummycon_putcs(struct vc_data *vc, const unsigned short *s, + int count, int ypos, int xpos) { } +static void dummycon_cursor(struct vc_data *vc, int mode) { } + +static bool dummycon_scroll(struct vc_data *vc, unsigned int top, + unsigned int bottom, enum con_scroll dir, + unsigned int lines) +{ + return false; +} + +static int dummycon_switch(struct vc_data *vc) { - return 0; + return 0; }
-#define DUMMY (void *)dummycon_dummy +static int dummycon_blank(struct vc_data *vc, int blank, int mode_switch) +{ + return 0; +} + +static int dummycon_font_set(struct vc_data *vc, struct console_font *font, + unsigned int flags) +{ + return 0; +} + +static int dummycon_font_default(struct vc_data *vc, + struct console_font *font, char *name) +{ + return 0; +} + +static int dummycon_font_copy(struct vc_data *vc, int con) +{ + return 0; +}
/* * The console `switch' structure for the dummy console @@ -55,19 +90,19 @@ static int dummycon_dummy(void) */
const struct consw dummy_con = { - .owner = THIS_MODULE, - .con_startup = dummycon_startup, - .con_init = dummycon_init, - .con_deinit = DUMMY, - .con_clear = DUMMY, - .con_putc = DUMMY, - .con_putcs = DUMMY, - .con_cursor = DUMMY, - .con_scroll = DUMMY, - .con_switch = DUMMY, - .con_blank = DUMMY, - .con_font_set = DUMMY, - .con_font_default = DUMMY, - .con_font_copy = DUMMY, + .owner = THIS_MODULE, + .con_startup = dummycon_startup, + .con_init = dummycon_init, + .con_deinit = dummycon_deinit, + .con_clear = dummycon_clear, + .con_putc = dummycon_putc, + .con_putcs = dummycon_putcs, + .con_cursor = dummycon_cursor, + .con_scroll = dummycon_scroll, + .con_switch = dummycon_switch, + .con_blank = dummycon_blank, + .con_font_set = dummycon_font_set, + .con_font_default = dummycon_font_default, + .con_font_copy = dummycon_font_copy, }; EXPORT_SYMBOL_GPL(dummy_con); diff --git a/drivers/video/console/newport_con.c b/drivers/video/console/newport_con.c index 42d02a206059..6897bd0fc00e 100644 --- a/drivers/video/console/newport_con.c +++ b/drivers/video/console/newport_con.c @@ -673,14 +673,14 @@ static bool newport_scroll(struct vc_data *vc, unsigned int t, unsigned int b, return true; }
-static int newport_dummy(struct vc_data *c) +static int newport_set_origin(struct vc_data *vc) { return 0; }
-#define DUMMY (void *) newport_dummy +static void newport_save_screen(struct vc_data *vc) { }
-const struct consw newport_con = { +static const struct consw newport_con = { .owner = THIS_MODULE, .con_startup = newport_startup, .con_init = newport_init, @@ -694,8 +694,8 @@ const struct consw newport_con = { .con_blank = newport_blank, .con_font_set = newport_font_set, .con_font_default = newport_font_default, - .con_set_origin = DUMMY, - .con_save_screen = DUMMY + .con_set_origin = newport_set_origin, + .con_save_screen = newport_save_screen };
static int newport_probe(struct gio_device *dev, diff --git a/drivers/video/console/vgacon.c b/drivers/video/console/vgacon.c index a17ba1465815..f09e17b60e45 100644 --- a/drivers/video/console/vgacon.c +++ b/drivers/video/console/vgacon.c @@ -1272,7 +1272,8 @@ static int vgacon_adjust_height(struct vc_data *vc, unsigned fontheight) return 0; }
-static int vgacon_font_set(struct vc_data *c, struct console_font *font, unsigned flags) +static int vgacon_font_set(struct vc_data *c, struct console_font *font, + unsigned int flags) { unsigned charcount = font->charcount; int rc; @@ -1407,21 +1408,20 @@ static bool vgacon_scroll(struct vc_data *c, unsigned int t, unsigned int b, * The console `switch' structure for the VGA based console */
-static int vgacon_dummy(struct vc_data *c) -{ - return 0; -} - -#define DUMMY (void *) vgacon_dummy +static void vgacon_clear(struct vc_data *vc, int sy, int sx, int height, + int width) { } +static void vgacon_putc(struct vc_data *vc, int c, int ypos, int xpos) { } +static void vgacon_putcs(struct vc_data *vc, const unsigned short *s, + int count, int ypos, int xpos) { }
const struct consw vga_con = { .owner = THIS_MODULE, .con_startup = vgacon_startup, .con_init = vgacon_init, .con_deinit = vgacon_deinit, - .con_clear = DUMMY, - .con_putc = DUMMY, - .con_putcs = DUMMY, + .con_clear = vgacon_clear, + .con_putc = vgacon_putc, + .con_putcs = vgacon_putcs, .con_cursor = vgacon_cursor, .con_scroll = vgacon_scroll, .con_switch = vgacon_switch, diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c index 5baf7bc054e1..3e330e0f56ed 100644 --- a/drivers/video/fbdev/core/fbcon.c +++ b/drivers/video/fbdev/core/fbcon.c @@ -2595,7 +2595,8 @@ static int fbcon_copy_font(struct vc_data *vc, int con) * is ever implemented. */
-static int fbcon_set_font(struct vc_data *vc, struct console_font *font, unsigned flags) +static int fbcon_set_font(struct vc_data *vc, struct console_font *font, + unsigned int flags) { struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; unsigned charcount = font->charcount;