| 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
| ||
|
Date: Wed, 19 Feb 2020 08:39:47 +0100
From: Jiri Slaby <jslaby@...e.cz>
To: gregkh@...uxfoundation.org
Cc: linux-serial@...r.kernel.org, linux-kernel@...r.kernel.org,
Jiri Slaby <jslaby@...e.cz>
Subject: [PATCH 5/9] vt: selection, create struct from console selection globals
Move all the selection global variables to a structure vc_selection,
instantiated as vc_sel. This helps to group all the variables together
and see what should be protected by the embedded lock too.
It might be used later also for per-console selection support.
Signed-off-by: Jiri Slaby <jslaby@...e.cz>
---
drivers/tty/vt/selection.c | 94 +++++++++++++++++++-------------------
1 file changed, 48 insertions(+), 46 deletions(-)
diff --git a/drivers/tty/vt/selection.c b/drivers/tty/vt/selection.c
index 33f94293f45e..0cd7072b6a56 100644
--- a/drivers/tty/vt/selection.c
+++ b/drivers/tty/vt/selection.c
@@ -38,14 +38,17 @@
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 */
-static volatile int sel_start = -1; /* cleared by clear_selection */
-static int sel_end;
-static int sel_buffer_lth;
-static char *sel_buffer;
-static DEFINE_MUTEX(sel_lock);
+static struct vc_selection {
+ struct mutex lock;
+ struct vc_data *cons; /* must not be deallocated */
+ char *buffer;
+ unsigned int buf_len;
+ volatile int start; /* cleared by clear_selection */
+ int end;
+} vc_sel = {
+ .lock = __MUTEX_INITIALIZER(vc_sel.lock),
+ .start = -1,
+};
/* clear_selection, highlight and highlight_pointer can be called
from interrupt (via scrollback/front) */
@@ -53,22 +56,21 @@ static DEFINE_MUTEX(sel_lock);
/* set reverse video on characters s-e of console with selection. */
static inline void highlight(const int s, const int e)
{
- invert_screen(sel_cons, s, e-s+2, 1);
+ invert_screen(vc_sel.cons, s, e-s+2, 1);
}
/* use complementary color to show the pointer */
static inline void highlight_pointer(const int where)
{
- complement_pos(sel_cons, where);
+ complement_pos(vc_sel.cons, where);
}
static u32
sel_pos(int n, bool unicode)
{
if (unicode)
- return screen_glyph_unicode(sel_cons, n / 2);
- return inverse_translate(sel_cons, screen_glyph(sel_cons, n),
- 0);
+ return screen_glyph_unicode(vc_sel.cons, n / 2);
+ return inverse_translate(vc_sel.cons, screen_glyph(vc_sel.cons, n), 0);
}
/**
@@ -80,16 +82,16 @@ sel_pos(int n, bool unicode)
void clear_selection(void)
{
highlight_pointer(-1); /* hide the pointer */
- if (sel_start != -1) {
- highlight(sel_start, sel_end);
- sel_start = -1;
+ if (vc_sel.start != -1) {
+ highlight(vc_sel.start, vc_sel.end);
+ vc_sel.start = -1;
}
}
EXPORT_SYMBOL_GPL(clear_selection);
bool vc_is_sel(struct vc_data *vc)
{
- return vc == sel_cons;
+ return vc == vc_sel.cons;
}
/*
@@ -216,13 +218,13 @@ int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
return 0;
}
- if (ps > pe) /* make sel_start <= sel_end */
+ if (ps > pe) /* make vc_sel.start <= vc_sel.end */
swap(ps, pe);
- mutex_lock(&sel_lock);
- if (sel_cons != vc_cons[fg_console].d) {
+ mutex_lock(&vc_sel.lock);
+ if (vc_sel.cons != vc_cons[fg_console].d) {
clear_selection();
- sel_cons = vc_cons[fg_console].d;
+ vc_sel.cons = vc_cons[fg_console].d;
}
unicode = vt_do_kdgkbmode(fg_console) == K_UNICODE;
@@ -281,35 +283,35 @@ int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
if (isspace(sel_pos(pe, unicode)))
new_sel_end = pe;
}
- if (sel_start == -1) /* no current selection */
+ if (vc_sel.start == -1) /* no current selection */
highlight(new_sel_start, new_sel_end);
- else if (new_sel_start == sel_start)
+ else if (new_sel_start == vc_sel.start)
{
- if (new_sel_end == sel_end) /* no action required */
+ if (new_sel_end == vc_sel.end) /* no action required */
goto unlock;
- else if (new_sel_end > sel_end) /* extend to right */
- highlight(sel_end + 2, new_sel_end);
+ else if (new_sel_end > vc_sel.end) /* extend to right */
+ highlight(vc_sel.end + 2, new_sel_end);
else /* contract from right */
- highlight(new_sel_end + 2, sel_end);
+ highlight(new_sel_end + 2, vc_sel.end);
}
- else if (new_sel_end == sel_end)
+ else if (new_sel_end == vc_sel.end)
{
- if (new_sel_start < sel_start) /* extend to left */
- highlight(new_sel_start, sel_start - 2);
+ if (new_sel_start < vc_sel.start) /* extend to left */
+ highlight(new_sel_start, vc_sel.start - 2);
else /* contract from left */
- highlight(sel_start, new_sel_start - 2);
+ highlight(vc_sel.start, new_sel_start - 2);
}
else /* some other case; start selection from scratch */
{
clear_selection();
highlight(new_sel_start, new_sel_end);
}
- sel_start = new_sel_start;
- sel_end = new_sel_end;
+ vc_sel.start = new_sel_start;
+ vc_sel.end = new_sel_end;
/* Allocate a new buffer before freeing the old one ... */
/* chars can take up to 4 bytes with unicode */
- bp = kmalloc_array((sel_end - sel_start) / 2 + 1, unicode ? 4 : 1,
+ bp = kmalloc_array((vc_sel.end - vc_sel.start) / 2 + 1, unicode ? 4 : 1,
GFP_KERNEL);
if (!bp) {
printk(KERN_WARNING "selection: kmalloc() failed\n");
@@ -317,11 +319,11 @@ int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
ret = -ENOMEM;
goto unlock;
}
- kfree(sel_buffer);
- sel_buffer = bp;
+ kfree(vc_sel.buffer);
+ vc_sel.buffer = bp;
obp = bp;
- for (i = sel_start; i <= sel_end; i += 2) {
+ for (i = vc_sel.start; i <= vc_sel.end; i += 2) {
c = sel_pos(i, unicode);
if (unicode)
bp += store_utf8(c, bp);
@@ -339,9 +341,9 @@ int set_selection_kernel(struct tiocl_selection *v, struct tty_struct *tty)
obp = bp;
}
}
- sel_buffer_lth = bp - sel_buffer;
+ vc_sel.buf_len = bp - vc_sel.buffer;
unlock:
- mutex_unlock(&sel_lock);
+ mutex_unlock(&vc_sel.lock);
return ret;
}
EXPORT_SYMBOL_GPL(set_selection_kernel);
@@ -372,26 +374,26 @@ int paste_selection(struct tty_struct *tty)
tty_buffer_lock_exclusive(&vc->port);
add_wait_queue(&vc->paste_wait, &wait);
- mutex_lock(&sel_lock);
- while (sel_buffer && sel_buffer_lth > pasted) {
+ mutex_lock(&vc_sel.lock);
+ while (vc_sel.buffer && vc_sel.buf_len > pasted) {
set_current_state(TASK_INTERRUPTIBLE);
if (signal_pending(current)) {
ret = -EINTR;
break;
}
if (tty_throttled(tty)) {
- mutex_unlock(&sel_lock);
+ mutex_unlock(&vc_sel.lock);
schedule();
- mutex_lock(&sel_lock);
+ mutex_lock(&vc_sel.lock);
continue;
}
__set_current_state(TASK_RUNNING);
- count = sel_buffer_lth - pasted;
- count = tty_ldisc_receive_buf(ld, sel_buffer + pasted, NULL,
+ count = vc_sel.buf_len - pasted;
+ count = tty_ldisc_receive_buf(ld, vc_sel.buffer + pasted, NULL,
count);
pasted += count;
}
- mutex_unlock(&sel_lock);
+ mutex_unlock(&vc_sel.lock);
remove_wait_queue(&vc->paste_wait, &wait);
__set_current_state(TASK_RUNNING);
--
2.25.0
Powered by blists - more mailing lists