diff options
Diffstat (limited to 'drivers/tty/vt/selection.c')
| -rw-r--r-- | drivers/tty/vt/selection.c | 58 |
1 files changed, 43 insertions, 15 deletions
diff --git a/drivers/tty/vt/selection.c b/drivers/tty/vt/selection.c index 7a0a12ae5458..8e9b4be97a2d 100644 --- a/drivers/tty/vt/selection.c +++ b/drivers/tty/vt/selection.c @@ -30,6 +30,7 @@ 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 */ @@ -61,10 +62,14 @@ 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); @@ -74,7 +79,7 @@ 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 */ @@ -91,10 +96,20 @@ 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? */ @@ -130,7 +145,16 @@ 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; @@ -138,7 +162,7 @@ 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(); @@ -182,7 +206,11 @@ 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) { @@ -302,7 +330,8 @@ int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *t * queue of the tty associated with the current console. * Invoked by ioctl(). * - * Locking: always called with BTM from vt_ioctl + * Locking: called without locks. Calls the ldisc wrongly with + * unsafe methods, */ int paste_selection(struct tty_struct *tty) { @@ -317,13 +346,12 @@ int paste_selection(struct tty_struct *tty) poke_blanked_console(); console_unlock(); + /* FIXME: wtf is this supposed to achieve ? */ ld = tty_ldisc_ref(tty); - if (!ld) { - tty_unlock(); + if (!ld) ld = tty_ldisc_ref_wait(tty); - tty_lock(); - } + /* FIXME: this is completely unsafe */ add_wait_queue(&vc->paste_wait, &wait); while (sel_buffer && sel_buffer_lth > pasted) { set_current_state(TASK_INTERRUPTIBLE); |