lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Message-Id: <72c954371ed9b1d050901b2d498a979017de8a3c.1604306433.git.yepeilin.cs@gmail.com> Date: Mon, 2 Nov 2020 04:37:55 -0500 From: Peilin Ye <yepeilin.cs@...il.com> To: Daniel Vetter <daniel.vetter@...ll.ch>, Greg Kroah-Hartman <gregkh@...uxfoundation.org>, Jiri Slaby <jirislaby@...nel.org>, Thomas Winischhofer <thomas@...ischhofer.net> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>, Nicolas Pitre <nico@...xnic.net>, "Gustavo A . R . Silva" <gustavoars@...nel.org>, Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>, George Kennedy <george.kennedy@...cle.com>, Nathan Chancellor <natechancellor@...il.com>, Peter Rosin <peda@...ntia.se>, linux-kernel@...r.kernel.org, linux-usb@...r.kernel.org, dri-devel@...ts.freedesktop.org, linux-fbdev@...r.kernel.org, Peilin Ye <yepeilin.cs@...il.com> Subject: [PATCH v2 2/2] tty/vt: Avoid passing struct console_font_op to con_font_copy() con_font_op() is passing an entire `struct console_font_op *` to con_font_copy(), but con_font_copy() only uses `op->height`. Additionally, con_font_copy() is silently assigning the unsigned `op->height` to the signed `con`, then pass it to fbcon_copy_font(). Let con_font_copy() and fbcon_copy_font() pass an unsigned int directly. Also, add a comment in con_font_op() for less confusion, since ideally `op->height` should not be used as a console index, as the field name suggests. This patch depends on patch "console: Remove dummy con_font_op() callback implementations". Suggested-by: Daniel Vetter <daniel@...ll.ch> Signed-off-by: Peilin Ye <yepeilin.cs@...il.com> --- con_font_set(), con_font_get() and con_font_default() also pass an entire `console_font_op`. con_font_get() and con_font_default() actually update the structure (later copied to userspace), so let them be. con_font_set() does not update the structure, but it uses all fields of it except `op`. Avoiding passing `console_font_op` to con_font_set() will thus make its signature pretty long (6 parameters). Changes in v2: - Remove redundant `con < 0` check in con_font_copy() (kernel test robot <lkp@...el.com>) - Remove unnecessary range check in fbcon_copy_font(). con_font_copy() calls vc_cons_allocated(), which does the check - Do not Cc: stable - Rewrite the title and commit message accordingly drivers/tty/vt/vt.c | 8 ++++---- drivers/video/fbdev/core/fbcon.c | 2 +- include/linux/console.h | 2 +- 3 files changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index 9506a76f3ab6..27821ef97b13 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -4704,9 +4704,8 @@ static int con_font_default(struct vc_data *vc, struct console_font_op *op) return rc; } -static int con_font_copy(struct vc_data *vc, struct console_font_op *op) +static int con_font_copy(struct vc_data *vc, unsigned int con) { - int con = op->height; int rc; @@ -4715,7 +4714,7 @@ static int con_font_copy(struct vc_data *vc, struct console_font_op *op) rc = -EINVAL; else if (!vc->vc_sw->con_font_copy) rc = -ENOSYS; - else if (con < 0 || !vc_cons_allocated(con)) + else if (!vc_cons_allocated(con)) rc = -ENOTTY; else if (con == vc->vc_num) /* nothing to do */ rc = 0; @@ -4735,7 +4734,8 @@ int con_font_op(struct vc_data *vc, struct console_font_op *op) case KD_FONT_OP_SET_DEFAULT: return con_font_default(vc, op); case KD_FONT_OP_COPY: - return con_font_copy(vc, op); + /* uses op->height as a console index */ + return con_font_copy(vc, op->height); } return -ENOSYS; } diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c index cef437817b0d..cb5b5705ea71 100644 --- a/drivers/video/fbdev/core/fbcon.c +++ b/drivers/video/fbdev/core/fbcon.c @@ -2451,7 +2451,7 @@ static int fbcon_do_set_font(struct vc_data *vc, int w, int h, return 0; } -static int fbcon_copy_font(struct vc_data *vc, int con) +static int fbcon_copy_font(struct vc_data *vc, unsigned int con) { struct fbcon_display *od = &fb_display[con]; struct console_font *f = &vc->vc_font; diff --git a/include/linux/console.h b/include/linux/console.h index 4b1e26c4cb42..34855d3f2afd 100644 --- a/include/linux/console.h +++ b/include/linux/console.h @@ -62,7 +62,7 @@ struct consw { int (*con_font_get)(struct vc_data *vc, struct console_font *font); int (*con_font_default)(struct vc_data *vc, struct console_font *font, char *name); - int (*con_font_copy)(struct vc_data *vc, int con); + int (*con_font_copy)(struct vc_data *vc, unsigned int con); int (*con_resize)(struct vc_data *vc, unsigned int width, unsigned int height, unsigned int user); void (*con_set_palette)(struct vc_data *vc, -- 2.25.1
Powered by blists - more mailing lists