diff options
Diffstat (limited to 'drivers/tty/vt/selection.c')
| -rw-r--r-- | drivers/tty/vt/selection.c | 76 |
1 files changed, 49 insertions, 27 deletions
diff --git a/drivers/tty/vt/selection.c b/drivers/tty/vt/selection.c index ebae344ce91..ea27804d87a 100644 --- a/drivers/tty/vt/selection.c +++ b/drivers/tty/vt/selection.c @@ -1,6 +1,4 @@ /* - * linux/drivers/char/selection.c - * * This module exports the functions: * * 'int set_selection(struct tiocl_selection __user *, struct tty_struct *)' @@ -26,13 +24,14 @@ #include <linux/selection.h> #include <linux/tiocl.h> #include <linux/console.h> -#include <linux/smp_lock.h> +#include <linux/tty_flip.h> /* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */ #define isspace(c) ((c) == ' ') extern void poke_blanked_console(void); +/* FIXME: all this needs locking */ /* Variables for selection control. */ /* Use a dynamic buffer, instead of static (Dec 1994) */ struct vc_data *sel_cons; /* must not be deallocated */ @@ -64,10 +63,14 @@ sel_pos(int n) use_unicode); } -/* remove the current selection highlight, if any, - from the console holding the selection. */ -void -clear_selection(void) { +/** + * clear_selection - remove current selection + * + * Remove the current selection highlight, if any from the console + * holding the selection. The caller must hold the console lock. + */ +void clear_selection(void) +{ highlight_pointer(-1); /* hide the pointer */ if (sel_start != -1) { highlight(sel_start, sel_end); @@ -77,7 +80,7 @@ clear_selection(void) { /* * User settable table: what characters are to be considered alphabetic? - * 256 bits + * 256 bits. Locked by the console lock. */ static u32 inwordLut[8]={ 0x00000000, /* control chars */ @@ -94,10 +97,20 @@ static inline int inword(const u16 c) { return c > 0xff || (( inwordLut[c>>5] >> (c & 0x1F) ) & 1); } -/* set inwordLut contents. Invoked by ioctl(). */ +/** + * set loadlut - load the LUT table + * @p: user table + * + * Load the LUT table from user space. The caller must hold the console + * lock. Make a temporary copy so a partial update doesn't make a mess. + */ int sel_loadlut(char __user *p) { - return copy_from_user(inwordLut, (u32 __user *)(p+4), 32) ? -EFAULT : 0; + u32 tmplut[8]; + if (copy_from_user(tmplut, (u32 __user *)(p+4), 32)) + return -EFAULT; + memcpy(inwordLut, tmplut, 32); + return 0; } /* does screen address p correspond to character at LH/RH edge of screen? */ @@ -133,7 +146,16 @@ static int store_utf8(u16 c, char *p) } } -/* set the current selection. Invoked by ioctl() or by kernel code. */ +/** + * set_selection - set the current selection. + * @sel: user selection info + * @tty: the console tty + * + * Invoked by the ioctl handle for the vt layer. + * + * The entire selection process is managed under the console_lock. It's + * a lot under the lock but its hardly a performance path + */ int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *tty) { struct vc_data *vc = vc_cons[fg_console].d; @@ -141,7 +163,7 @@ int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *t char *bp, *obp; int i, ps, pe, multiplier; u16 c; - struct kbd_struct *kbd = kbd_table + fg_console; + int mode; poke_blanked_console(); @@ -185,7 +207,11 @@ int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *t clear_selection(); sel_cons = vc_cons[fg_console].d; } - use_unicode = kbd && kbd->kbdmode == VC_UNICODE; + mode = vt_do_kdgkbmode(fg_console); + if (mode == K_UNICODE) + use_unicode = 1; + else + use_unicode = 0; switch (sel_mode) { @@ -304,6 +330,9 @@ int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *t /* Insert the contents of the selection buffer into the * queue of the tty associated with the current console. * Invoked by ioctl(). + * + * Locking: called without locks. Calls the ldisc wrongly with + * unsafe methods, */ int paste_selection(struct tty_struct *tty) { @@ -313,19 +342,12 @@ int paste_selection(struct tty_struct *tty) struct tty_ldisc *ld; DECLARE_WAITQUEUE(wait, current); - /* always called with BTM from vt_ioctl */ - WARN_ON(!tty_locked()); - - acquire_console_sem(); + console_lock(); poke_blanked_console(); - release_console_sem(); + console_unlock(); - ld = tty_ldisc_ref(tty); - if (!ld) { - tty_unlock(); - ld = tty_ldisc_ref_wait(tty); - tty_lock(); - } + ld = tty_ldisc_ref_wait(tty); + tty_buffer_lock_exclusive(&vc->port); add_wait_queue(&vc->paste_wait, &wait); while (sel_buffer && sel_buffer_lth > pasted) { @@ -335,14 +357,14 @@ int paste_selection(struct tty_struct *tty) continue; } count = sel_buffer_lth - pasted; - count = min(count, tty->receive_room); - tty->ldisc->ops->receive_buf(tty, sel_buffer + pasted, - NULL, count); + count = tty_ldisc_receive_buf(ld, sel_buffer + pasted, NULL, + count); pasted += count; } remove_wait_queue(&vc->paste_wait, &wait); __set_current_state(TASK_RUNNING); + tty_buffer_unlock_exclusive(&vc->port); tty_ldisc_deref(ld); return 0; } |