From 2fe16088c3c77cd96e64363927ddc98f66de8e8b Mon Sep 17 00:00:00 2001 From: "Jiri Slaby (SUSE)" Date: Thu, 14 Aug 2025 09:24:54 +0200 Subject: [PATCH] tty/vt: use guard()s in con_font_set/get() and con_{set,get}_unimap() Having all the new guards, use them in the 8250_rsa code. This improves readability, makes error handling easier, and marks locked portions of code explicit. The new __free()-annotated declarations are moved to the allocation points as is preferred: https://lore.kernel.org/all/CAHk-=wjvh_LUpa=864joG2JJXs3+viO-kLzLidR2JLyMr4MNwA@mail.gmail.com/ Except font_data in con_font_get(). The scope in there would not match the expected lifetime. But the declaration is moved closer. Signed-off-by: "Jiri Slaby (SUSE)" Link: https://lore.kernel.org/r/20250814072456.182853-15-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/tty/vt/consolemap.c | 84 ++++++++++++++++------------------ drivers/tty/vt/vt.c | 89 +++++++++++++++++-------------------- 2 files changed, 78 insertions(+), 95 deletions(-) diff --git a/drivers/tty/vt/consolemap.c b/drivers/tty/vt/consolemap.c index bb4bb272ebec5..8eb9d745a8685 100644 --- a/drivers/tty/vt/consolemap.c +++ b/drivers/tty/vt/consolemap.c @@ -637,32 +637,28 @@ static struct uni_pagedict *con_unshare_unimap(struct vc_data *vc, int con_set_unimap(struct vc_data *vc, ushort ct, struct unipair __user *list) { - int err = 0, err1; struct uni_pagedict *dict; - struct unipair *unilist, *plist; + struct unipair *plist; + int err = 0; if (!ct) return 0; - unilist = vmemdup_array_user(list, ct, sizeof(*unilist)); + struct unipair *unilist __free(kvfree) = vmemdup_array_user(list, ct, sizeof(*unilist)); if (IS_ERR(unilist)) return PTR_ERR(unilist); - console_lock(); + guard(console_lock)(); /* Save original vc_unipagdir_loc in case we allocate a new one */ dict = *vc->uni_pagedict_loc; - if (!dict) { - err = -EINVAL; - goto out_unlock; - } + if (!dict) + return -EINVAL; if (dict->refcount > 1) { dict = con_unshare_unimap(vc, dict); - if (IS_ERR(dict)) { - err = PTR_ERR(dict); - goto out_unlock; - } + if (IS_ERR(dict)) + return PTR_ERR(dict); } else if (dict == dflt) { dflt = NULL; } @@ -671,7 +667,7 @@ int con_set_unimap(struct vc_data *vc, ushort ct, struct unipair __user *list) * Insert user specified unicode pairs into new table. */ for (plist = unilist; ct; ct--, plist++) { - err1 = con_insert_unipair(dict, plist->unicode, plist->fontpos); + int err1 = con_insert_unipair(dict, plist->unicode, plist->fontpos); if (err1) err = err1; } @@ -680,15 +676,12 @@ int con_set_unimap(struct vc_data *vc, ushort ct, struct unipair __user *list) * Merge with fontmaps of any other virtual consoles. */ if (con_unify_unimap(vc, dict)) - goto out_unlock; + return err; for (enum translation_map m = FIRST_MAP; m <= LAST_MAP; m++) set_inverse_transl(vc, dict, m); set_inverse_trans_unicode(dict); -out_unlock: - console_unlock(); - kvfree(unilist); return err; } @@ -787,50 +780,49 @@ int con_get_unimap(struct vc_data *vc, ushort ct, ushort __user *uct, { ushort ect; struct uni_pagedict *dict; - struct unipair *unilist; unsigned int d, r, g; - int ret = 0; - unilist = kvmalloc_array(ct, sizeof(*unilist), GFP_KERNEL); + struct unipair *unilist __free(kvfree) = kvmalloc_array(ct, sizeof(*unilist), GFP_KERNEL); if (!unilist) return -ENOMEM; - console_lock(); - - ect = 0; - dict = *vc->uni_pagedict_loc; - if (!dict) - goto unlock; - - for (d = 0; d < UNI_DIRS; d++) { - u16 **dir = dict->uni_pgdir[d]; - if (!dir) - continue; + scoped_guard(console_lock) { + ect = 0; + dict = *vc->uni_pagedict_loc; + if (!dict) + break; - for (r = 0; r < UNI_DIR_ROWS; r++) { - u16 *row = dir[r]; - if (!row) + for (d = 0; d < UNI_DIRS; d++) { + u16 **dir = dict->uni_pgdir[d]; + if (!dir) continue; - for (g = 0; g < UNI_ROW_GLYPHS; g++, row++) { - if (*row >= MAX_GLYPH) + for (r = 0; r < UNI_DIR_ROWS; r++) { + u16 *row = dir[r]; + if (!row) continue; - if (ect < ct) { - unilist[ect].unicode = UNI(d, r, g); - unilist[ect].fontpos = *row; + + for (g = 0; g < UNI_ROW_GLYPHS; g++, row++) { + if (*row >= MAX_GLYPH) + continue; + if (ect < ct) { + unilist[ect].unicode = UNI(d, r, g); + unilist[ect].fontpos = *row; + } + ect++; } - ect++; } } } -unlock: - console_unlock(); + if (copy_to_user(list, unilist, min(ect, ct) * sizeof(*unilist))) - ret = -EFAULT; + return -EFAULT; if (put_user(ect, uct)) - ret = -EFAULT; - kvfree(unilist); - return ret ? ret : (ect <= ct) ? 0 : -ENOMEM; + return -EFAULT; + if (ect > ct) + return -ENOMEM; + + return 0; } /* diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index 62049ceb34de6..100d6cb26887e 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -4801,57 +4801,51 @@ void reset_palette(struct vc_data *vc) static int con_font_get(struct vc_data *vc, struct console_font_op *op) { struct console_font font; - int rc = -EINVAL; int c; unsigned int vpitch = op->op == KD_FONT_OP_GET_TALL ? op->height : 32; if (vpitch > max_font_height) return -EINVAL; + void *font_data __free(kvfree) = NULL; if (op->data) { - font.data = kvzalloc(max_font_size, GFP_KERNEL); + font.data = font_data = kvzalloc(max_font_size, GFP_KERNEL); if (!font.data) return -ENOMEM; } else font.data = NULL; - console_lock(); - if (vc->vc_mode != KD_TEXT) - rc = -EINVAL; - else if (vc->vc_sw->con_font_get) - rc = vc->vc_sw->con_font_get(vc, &font, vpitch); - else - rc = -ENOSYS; - console_unlock(); + scoped_guard(console_lock) { + if (vc->vc_mode != KD_TEXT) + return -EINVAL; + if (!vc->vc_sw->con_font_get) + return -ENOSYS; - if (rc) - goto out; + int ret = vc->vc_sw->con_font_get(vc, &font, vpitch); + if (ret) + return ret; + } c = (font.width+7)/8 * vpitch * font.charcount; if (op->data && font.charcount > op->charcount) - rc = -ENOSPC; + return -ENOSPC; if (font.width > op->width || font.height > op->height) - rc = -ENOSPC; - if (rc) - goto out; + return -ENOSPC; op->height = font.height; op->width = font.width; op->charcount = font.charcount; if (op->data && copy_to_user(op->data, font.data, c)) - rc = -EFAULT; + return -EFAULT; -out: - kvfree(font.data); - return rc; + return 0; } static int con_font_set(struct vc_data *vc, const struct console_font_op *op) { struct console_font font; - int rc = -EINVAL; int size; unsigned int vpitch = op->op == KD_FONT_OP_SET_TALL ? op->height : 32; @@ -4870,7 +4864,7 @@ static int con_font_set(struct vc_data *vc, const struct console_font_op *op) if (size > max_font_size) return -ENOSPC; - font.data = memdup_user(op->data, size); + void *font_data __free(kfree) = font.data = memdup_user(op->data, size); if (IS_ERR(font.data)) return PTR_ERR(font.data); @@ -4878,18 +4872,17 @@ static int con_font_set(struct vc_data *vc, const struct console_font_op *op) font.width = op->width; font.height = op->height; - console_lock(); + guard(console_lock)(); + if (vc->vc_mode != KD_TEXT) - rc = -EINVAL; - else if (vc->vc_sw->con_font_set) { - if (vc_is_sel(vc)) - clear_selection(); - rc = vc->vc_sw->con_font_set(vc, &font, vpitch, op->flags); - } else - rc = -ENOSYS; - console_unlock(); - kfree(font.data); - return rc; + return -EINVAL; + if (!vc->vc_sw->con_font_set) + return -ENOSYS; + + if (vc_is_sel(vc)) + clear_selection(); + + return vc->vc_sw->con_font_set(vc, &font, vpitch, op->flags); } static int con_font_default(struct vc_data *vc, struct console_font_op *op) @@ -4897,8 +4890,6 @@ static int con_font_default(struct vc_data *vc, struct console_font_op *op) struct console_font font = {.width = op->width, .height = op->height}; char name[MAX_FONT_NAME]; char *s = name; - int rc; - if (!op->data) s = NULL; @@ -4907,23 +4898,23 @@ static int con_font_default(struct vc_data *vc, struct console_font_op *op) else name[MAX_FONT_NAME - 1] = 0; - console_lock(); - if (vc->vc_mode != KD_TEXT) { - console_unlock(); - return -EINVAL; - } - if (vc->vc_sw->con_font_default) { + scoped_guard(console_lock) { + if (vc->vc_mode != KD_TEXT) + return -EINVAL; + if (!vc->vc_sw->con_font_default) + return -ENOSYS; + if (vc_is_sel(vc)) clear_selection(); - rc = vc->vc_sw->con_font_default(vc, &font, s); - } else - rc = -ENOSYS; - console_unlock(); - if (!rc) { - op->width = font.width; - op->height = font.height; + int ret = vc->vc_sw->con_font_default(vc, &font, s); + if (ret) + return ret; } - return rc; + + op->width = font.width; + op->height = font.height; + + return 0; } int con_font_op(struct vc_data *vc, struct console_font_op *op) -- 2.47.3