From c396a5bf457fb60159dcedbd4f48d53a62be030a Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Mon, 26 Feb 2018 16:04:20 -0800 Subject: console: Expand dummy functions for CFI 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 Signed-off-by: Sami Tolvanen Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman --- drivers/video/console/dummycon.c | 69 ++++++++++++++++++++++++++++++---------- 1 file changed, 52 insertions(+), 17 deletions(-) (limited to 'drivers/video/console/dummycon.c') 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); -- cgit v1.2.3