From patchwork Tue Apr 5 21:03:21 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Vetter X-Patchwork-Id: 12801957 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4EC14C433FE for ; Tue, 5 Apr 2022 21:04:05 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 7A69C10E2F6; Tue, 5 Apr 2022 21:03:48 +0000 (UTC) Received: from mail-wm1-x332.google.com (mail-wm1-x332.google.com [IPv6:2a00:1450:4864:20::332]) by gabe.freedesktop.org (Postfix) with ESMTPS id 1C79210E36E for ; Tue, 5 Apr 2022 21:03:46 +0000 (UTC) Received: by mail-wm1-x332.google.com with SMTP id k124-20020a1ca182000000b0038c9cf6e2a6so438540wme.0 for ; Tue, 05 Apr 2022 14:03:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=OS2lajXUA0KG0+izVe6d6aMsv88+OgOENkHaPVcoRDk=; b=bIxTPIKjtRB43qDMQCvC4uWgOTAFtpBnR6m/eENHDpS92xvrUpAKWNT/TlasdgVypc F1beZAuuxZJ+ZdlJkOyAj0aBG7Rmqkw4ATMzX4aZy+rprTULFJt3Ek3hI4bBMOgO0G4n 5k/F/3/XRY+d0IOj9FsRc5Ouh+W+snrBfCdls= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=OS2lajXUA0KG0+izVe6d6aMsv88+OgOENkHaPVcoRDk=; b=wJfFfAdmidBB2tgjIJg7YpKbtZ3bP7bWksoEZodnLUIb9/w/hsWR4McDt+oWWWKDu6 nWuPO+XXKwaNG649bIhpWiKb4vS1v8rDoo1kU405qQXlP7nICYuW2hFIcX7Pb5eaJ43N sdeQil77jGLE6J8bGzCL9FDoFJaOKtraMewfYWsJGm0b95TYyEpnCv0lU06Ivh7ed4OE 0ZzJIYH15UzWzCg984+tYOk8lBiSNPK5ZwXiDcNQgJ5HYBQNj+eW2RkW9W92QGF33L8R CVn/PcfVNdSznnv5BCmucpZ1ioNsLMePqZExSb26nPBVy9WNRkoaMDkqW+7haHkXoeIT CiOQ== X-Gm-Message-State: AOAM530g0DXTHPJrIfLY5IPCB6tWZ7eOy/ifzIm4dhS2gULjYhNliiY5 dfauyEKXoc8h+ZY1RkyucJG3ag== X-Google-Smtp-Source: ABdhPJzMkdR8YYCbnATEgbV6+5ShrWFFtX9S39FWSZYzIjaysJwHNbbZrdetAxkNxN1dlXbm0Fq2BQ== X-Received: by 2002:a05:600c:3d0e:b0:38c:9b5e:52c0 with SMTP id bh14-20020a05600c3d0e00b0038c9b5e52c0mr4508462wmb.3.1649192624611; Tue, 05 Apr 2022 14:03:44 -0700 (PDT) Received: from phenom.ffwll.local ([2a02:168:57f4:0:efd0:b9e5:5ae6:c2fa]) by smtp.gmail.com with ESMTPSA id az19-20020a05600c601300b0038cadf3aa69sm4858569wmb.36.2022.04.05.14.03.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 05 Apr 2022 14:03:44 -0700 (PDT) From: Daniel Vetter To: DRI Development Date: Tue, 5 Apr 2022 23:03:21 +0200 Message-Id: <20220405210335.3434130-4-daniel.vetter@ffwll.ch> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220405210335.3434130-1-daniel.vetter@ffwll.ch> References: <20220405210335.3434130-1-daniel.vetter@ffwll.ch> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH v3 03/17] fbcon: Introduce wrapper for console->fb_info lookup X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Du Cheng , Tetsuo Handa , Daniel Vetter , Intel Graphics Development , Thomas Zimmermann , Greg Kroah-Hartman , Daniel Vetter , Sam Ravnborg , Helge Deller Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Half of it is protected by console_lock, but the other half is a lot more awkward: Registration/deregistration of fbdev are serialized, but we don't really clear out anything in con2fb_map and so there's potential for use-after free mixups. First step is to encapsulate the lookup. Acked-by: Thomas Zimmermann Acked-by: Sam Ravnborg Signed-off-by: Daniel Vetter Cc: Helge Deller Cc: Daniel Vetter Cc: Greg Kroah-Hartman Cc: Tetsuo Handa Cc: Du Cheng Cc: Claudio Suarez Cc: Thomas Zimmermann --- drivers/video/fbdev/core/fbcon.c | 76 ++++++++++++++++++-------------- 1 file changed, 44 insertions(+), 32 deletions(-) diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c index e925bb608e25..b75e638cb83d 100644 --- a/drivers/video/fbdev/core/fbcon.c +++ b/drivers/video/fbdev/core/fbcon.c @@ -110,6 +110,18 @@ static struct fbcon_display fb_display[MAX_NR_CONSOLES]; static signed char con2fb_map[MAX_NR_CONSOLES]; static signed char con2fb_map_boot[MAX_NR_CONSOLES]; +static struct fb_info *fbcon_info_from_console(int console) +{ + WARN_CONSOLE_UNLOCKED(); + + /* + * Note that only con2fb_map is protected by the console lock, + * registered_fb is protected by a separate mutex. This lookup can + * therefore race. + */ + return registered_fb[con2fb_map[console]]; +} + static int logo_lines; /* logo_shown is an index to vc_cons when >= 0; otherwise follows FBCON_LOGO enums. */ @@ -199,7 +211,7 @@ static void fbcon_rotate(struct fb_info *info, u32 rotate) if (!ops || ops->currcon == -1) return; - fb_info = registered_fb[con2fb_map[ops->currcon]]; + fb_info = fbcon_info_from_console(ops->currcon); if (info == fb_info) { struct fbcon_display *p = &fb_display[ops->currcon]; @@ -226,7 +238,7 @@ static void fbcon_rotate_all(struct fb_info *info, u32 rotate) for (i = first_fb_vc; i <= last_fb_vc; i++) { vc = vc_cons[i].d; if (!vc || vc->vc_mode != KD_TEXT || - registered_fb[con2fb_map[i]] != info) + fbcon_info_from_console(i) != info) continue; p = &fb_display[vc->vc_num]; @@ -356,7 +368,7 @@ static void fb_flashcursor(struct work_struct *work) vc = vc_cons[ops->currcon].d; if (!vc || !con_is_visible(vc) || - registered_fb[con2fb_map[vc->vc_num]] != info || + fbcon_info_from_console(vc->vc_num) != info || vc->vc_deccm != 1) { console_unlock(); return; @@ -791,7 +803,7 @@ static void con2fb_init_display(struct vc_data *vc, struct fb_info *info, if (show_logo) { struct vc_data *fg_vc = vc_cons[fg_console].d; struct fb_info *fg_info = - registered_fb[con2fb_map[fg_console]]; + fbcon_info_from_console(fg_console); fbcon_prepare_logo(fg_vc, fg_info, fg_vc->vc_cols, fg_vc->vc_rows, fg_vc->vc_cols, @@ -1014,7 +1026,7 @@ static void fbcon_init(struct vc_data *vc, int init) if (con2fb_map[vc->vc_num] == -1) con2fb_map[vc->vc_num] = info_idx; - info = registered_fb[con2fb_map[vc->vc_num]]; + info = fbcon_info_from_console(vc->vc_num); if (logo_shown < 0 && console_loglevel <= CONSOLE_LOGLEVEL_QUIET) logo_shown = FBCON_LOGO_DONTSHOW; @@ -1231,7 +1243,7 @@ static void fbcon_deinit(struct vc_data *vc) static void fbcon_clear(struct vc_data *vc, int sy, int sx, int height, int width) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_ops *ops = info->fbcon_par; struct fbcon_display *p = &fb_display[vc->vc_num]; @@ -1269,7 +1281,7 @@ static void fbcon_clear(struct vc_data *vc, int sy, int sx, int height, static void fbcon_putcs(struct vc_data *vc, const unsigned short *s, int count, int ypos, int xpos) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_display *p = &fb_display[vc->vc_num]; struct fbcon_ops *ops = info->fbcon_par; @@ -1289,7 +1301,7 @@ static void fbcon_putc(struct vc_data *vc, int c, int ypos, int xpos) static void fbcon_clear_margins(struct vc_data *vc, int bottom_only) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_ops *ops = info->fbcon_par; if (!fbcon_is_inactive(vc, info)) @@ -1298,7 +1310,7 @@ static void fbcon_clear_margins(struct vc_data *vc, int bottom_only) static void fbcon_cursor(struct vc_data *vc, int mode) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_ops *ops = info->fbcon_par; int c = scr_readw((u16 *) vc->vc_pos); @@ -1392,7 +1404,7 @@ static void fbcon_set_disp(struct fb_info *info, struct fb_var_screeninfo *var, static __inline__ void ywrap_up(struct vc_data *vc, int count) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_ops *ops = info->fbcon_par; struct fbcon_display *p = &fb_display[vc->vc_num]; @@ -1411,7 +1423,7 @@ static __inline__ void ywrap_up(struct vc_data *vc, int count) static __inline__ void ywrap_down(struct vc_data *vc, int count) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_ops *ops = info->fbcon_par; struct fbcon_display *p = &fb_display[vc->vc_num]; @@ -1430,7 +1442,7 @@ static __inline__ void ywrap_down(struct vc_data *vc, int count) static __inline__ void ypan_up(struct vc_data *vc, int count) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_display *p = &fb_display[vc->vc_num]; struct fbcon_ops *ops = info->fbcon_par; @@ -1454,7 +1466,7 @@ static __inline__ void ypan_up(struct vc_data *vc, int count) static __inline__ void ypan_up_redraw(struct vc_data *vc, int t, int count) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_ops *ops = info->fbcon_par; struct fbcon_display *p = &fb_display[vc->vc_num]; @@ -1478,7 +1490,7 @@ static __inline__ void ypan_up_redraw(struct vc_data *vc, int t, int count) static __inline__ void ypan_down(struct vc_data *vc, int count) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_display *p = &fb_display[vc->vc_num]; struct fbcon_ops *ops = info->fbcon_par; @@ -1502,7 +1514,7 @@ static __inline__ void ypan_down(struct vc_data *vc, int count) static __inline__ void ypan_down_redraw(struct vc_data *vc, int t, int count) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_ops *ops = info->fbcon_par; struct fbcon_display *p = &fb_display[vc->vc_num]; @@ -1666,7 +1678,7 @@ static void fbcon_redraw(struct vc_data *vc, struct fbcon_display *p, static void fbcon_bmove_rec(struct vc_data *vc, struct fbcon_display *p, int sy, int sx, int dy, int dx, int height, int width, u_int y_break) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_ops *ops = info->fbcon_par; u_int b; @@ -1708,7 +1720,7 @@ static void fbcon_bmove_rec(struct vc_data *vc, struct fbcon_display *p, int sy, static void fbcon_bmove(struct vc_data *vc, int sy, int sx, int dy, int dx, int height, int width) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_display *p = &fb_display[vc->vc_num]; if (fbcon_is_inactive(vc, info)) @@ -1731,7 +1743,7 @@ static void fbcon_bmove(struct vc_data *vc, int sy, int sx, int dy, int dx, static bool fbcon_scroll(struct vc_data *vc, unsigned int t, unsigned int b, enum con_scroll dir, unsigned int count) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_display *p = &fb_display[vc->vc_num]; int scroll_partial = info->flags & FBINFO_PARTIAL_PAN_OK; @@ -1996,7 +2008,7 @@ static void updatescrollmode(struct fbcon_display *p, static int fbcon_resize(struct vc_data *vc, unsigned int width, unsigned int height, unsigned int user) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_ops *ops = info->fbcon_par; struct fbcon_display *p = &fb_display[vc->vc_num]; struct fb_var_screeninfo var = info->var; @@ -2065,7 +2077,7 @@ static int fbcon_switch(struct vc_data *vc) struct fb_var_screeninfo var; int i, ret, prev_console; - info = registered_fb[con2fb_map[vc->vc_num]]; + info = fbcon_info_from_console(vc->vc_num); ops = info->fbcon_par; if (logo_shown >= 0) { @@ -2079,7 +2091,7 @@ static int fbcon_switch(struct vc_data *vc) prev_console = ops->currcon; if (prev_console != -1) - old_info = registered_fb[con2fb_map[prev_console]]; + old_info = fbcon_info_from_console(prev_console); /* * FIXME: If we have multiple fbdev's loaded, we need to * update all info->currcon. Perhaps, we can place this @@ -2202,7 +2214,7 @@ static void fbcon_generic_blank(struct vc_data *vc, struct fb_info *info, static int fbcon_blank(struct vc_data *vc, int blank, int mode_switch) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_ops *ops = info->fbcon_par; if (mode_switch) { @@ -2244,7 +2256,7 @@ static int fbcon_blank(struct vc_data *vc, int blank, int mode_switch) static int fbcon_debug_enter(struct vc_data *vc) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_ops *ops = info->fbcon_par; ops->save_graphics = ops->graphics; @@ -2257,7 +2269,7 @@ static int fbcon_debug_enter(struct vc_data *vc) static int fbcon_debug_leave(struct vc_data *vc) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_ops *ops = info->fbcon_par; ops->graphics = ops->save_graphics; @@ -2393,7 +2405,7 @@ static void set_vc_hi_font(struct vc_data *vc, bool set) static int fbcon_do_set_font(struct vc_data *vc, int w, int h, int charcount, const u8 * data, int userfont) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); struct fbcon_ops *ops = info->fbcon_par; struct fbcon_display *p = &fb_display[vc->vc_num]; int resize; @@ -2447,7 +2459,7 @@ static int fbcon_do_set_font(struct vc_data *vc, int w, int h, int charcount, 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]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); unsigned charcount = font->charcount; int w = font->width; int h = font->height; @@ -2511,7 +2523,7 @@ static int fbcon_set_font(struct vc_data *vc, struct console_font *font, static int fbcon_set_def_font(struct vc_data *vc, struct console_font *font, char *name) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); const struct font_desc *f; if (!name) @@ -2535,7 +2547,7 @@ static struct fb_cmap palette_cmap = { static void fbcon_set_palette(struct vc_data *vc, const unsigned char *table) { - struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]]; + struct fb_info *info = fbcon_info_from_console(vc->vc_num); int i, j, k, depth; u8 val; @@ -2651,7 +2663,7 @@ static void fbcon_modechanged(struct fb_info *info) return; vc = vc_cons[ops->currcon].d; if (vc->vc_mode != KD_TEXT || - registered_fb[con2fb_map[ops->currcon]] != info) + fbcon_info_from_console(ops->currcon) != info) return; p = &fb_display[vc->vc_num]; @@ -2691,7 +2703,7 @@ static void fbcon_set_all_vcs(struct fb_info *info) for (i = first_fb_vc; i <= last_fb_vc; i++) { vc = vc_cons[i].d; if (!vc || vc->vc_mode != KD_TEXT || - registered_fb[con2fb_map[i]] != info) + fbcon_info_from_console(i) != info) continue; if (con_is_visible(vc)) { @@ -2954,7 +2966,7 @@ void fbcon_fb_blanked(struct fb_info *info, int blank) vc = vc_cons[ops->currcon].d; if (vc->vc_mode != KD_TEXT || - registered_fb[con2fb_map[ops->currcon]] != info) + fbcon_info_from_console(ops->currcon) != info) return; if (con_is_visible(vc)) { @@ -2974,7 +2986,7 @@ void fbcon_new_modelist(struct fb_info *info) const struct fb_videomode *mode; for (i = first_fb_vc; i <= last_fb_vc; i++) { - if (registered_fb[con2fb_map[i]] != info) + if (fbcon_info_from_console(i) != info) continue; if (!fb_display[i].mode) continue;