Revision 89a8640279f8bb78aaf778d1fc5c4a6778f18064 authored by David Howells on 30 October 2009, 13:13:26 UTC, committed by Linus Torvalds on 31 October 2009, 19:11:37 UTC
Don't pass NULL pointers to fput() in the error handling paths of the NOMMU do_mmap_pgoff() as it can't handle it. The following can be used as a test program: int main() { static long long a[1024 * 1024 * 20] = { 0 }; return a;} Without the patch, the code oopses in atomic_long_dec_and_test() as called by fput() after the kernel complains that it can't allocate that big a chunk of memory. With the patch, the kernel just complains about the allocation size and then the program segfaults during execve() as execve() can't complete the allocation of all the new ELF program segments. Reported-by: Robin Getz <rgetz@blackfin.uclinux.org> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Robin Getz <rgetz@blackfin.uclinux.org> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 2e2ec95
selection.c
/*
* linux/drivers/char/selection.c
*
* This module exports the functions:
*
* 'int set_selection(struct tiocl_selection __user *, struct tty_struct *)'
* 'void clear_selection(void)'
* 'int paste_selection(struct tty_struct *)'
* 'int sel_loadlut(char __user *)'
*
* Now that /dev/vcs exists, most of this can disappear again.
*/
#include <linux/module.h>
#include <linux/tty.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <asm/uaccess.h>
#include <linux/kbd_kern.h>
#include <linux/vt_kern.h>
#include <linux/consolemap.h>
#include <linux/selection.h>
#include <linux/tiocl.h>
#include <linux/console.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);
/* Variables for selection control. */
/* Use a dynamic buffer, instead of static (Dec 1994) */
struct vc_data *sel_cons; /* must not be deallocated */
static int use_unicode;
static volatile int sel_start = -1; /* cleared by clear_selection */
static int sel_end;
static int sel_buffer_lth;
static char *sel_buffer;
/* clear_selection, highlight and highlight_pointer can be called
from interrupt (via scrollback/front) */
/* 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);
}
/* use complementary color to show the pointer */
static inline void highlight_pointer(const int where)
{
complement_pos(sel_cons, where);
}
static u16
sel_pos(int n)
{
return inverse_translate(sel_cons, screen_glyph(sel_cons, n),
use_unicode);
}
/* remove the current selection highlight, if any,
from the console holding the selection. */
void
clear_selection(void) {
highlight_pointer(-1); /* hide the pointer */
if (sel_start != -1) {
highlight(sel_start, sel_end);
sel_start = -1;
}
}
/*
* User settable table: what characters are to be considered alphabetic?
* 256 bits
*/
static u32 inwordLut[8]={
0x00000000, /* control chars */
0x03FF0000, /* digits */
0x87FFFFFE, /* uppercase and '_' */
0x07FFFFFE, /* lowercase */
0x00000000,
0x00000000,
0xFF7FFFFF, /* latin-1 accented letters, not multiplication sign */
0xFF7FFFFF /* latin-1 accented letters, not division sign */
};
static inline int inword(const u16 c) {
return c > 0xff || (( inwordLut[c>>5] >> (c & 0x1F) ) & 1);
}
/* set inwordLut contents. Invoked by ioctl(). */
int sel_loadlut(char __user *p)
{
return copy_from_user(inwordLut, (u32 __user *)(p+4), 32) ? -EFAULT : 0;
}
/* does screen address p correspond to character at LH/RH edge of screen? */
static inline int atedge(const int p, int size_row)
{
return (!(p % size_row) || !((p + 2) % size_row));
}
/* constrain v such that v <= u */
static inline unsigned short limit(const unsigned short v, const unsigned short u)
{
return (v > u) ? u : v;
}
/* stores the char in UTF8 and returns the number of bytes used (1-3) */
static int store_utf8(u16 c, char *p)
{
if (c < 0x80) {
/* 0******* */
p[0] = c;
return 1;
} else if (c < 0x800) {
/* 110***** 10****** */
p[0] = 0xc0 | (c >> 6);
p[1] = 0x80 | (c & 0x3f);
return 2;
} else {
/* 1110**** 10****** 10****** */
p[0] = 0xe0 | (c >> 12);
p[1] = 0x80 | ((c >> 6) & 0x3f);
p[2] = 0x80 | (c & 0x3f);
return 3;
}
}
/* set the current selection. Invoked by ioctl() or by kernel code. */
int set_selection(const struct tiocl_selection __user *sel, struct tty_struct *tty)
{
struct vc_data *vc = vc_cons[fg_console].d;
int sel_mode, new_sel_start, new_sel_end, spc;
char *bp, *obp;
int i, ps, pe, multiplier;
u16 c;
struct kbd_struct *kbd = kbd_table + fg_console;
poke_blanked_console();
{ unsigned short xs, ys, xe, ye;
if (!access_ok(VERIFY_READ, sel, sizeof(*sel)))
return -EFAULT;
__get_user(xs, &sel->xs);
__get_user(ys, &sel->ys);
__get_user(xe, &sel->xe);
__get_user(ye, &sel->ye);
__get_user(sel_mode, &sel->sel_mode);
xs--; ys--; xe--; ye--;
xs = limit(xs, vc->vc_cols - 1);
ys = limit(ys, vc->vc_rows - 1);
xe = limit(xe, vc->vc_cols - 1);
ye = limit(ye, vc->vc_rows - 1);
ps = ys * vc->vc_size_row + (xs << 1);
pe = ye * vc->vc_size_row + (xe << 1);
if (sel_mode == TIOCL_SELCLEAR) {
/* useful for screendump without selection highlights */
clear_selection();
return 0;
}
if (mouse_reporting() && (sel_mode & TIOCL_SELMOUSEREPORT)) {
mouse_report(tty, sel_mode & TIOCL_SELBUTTONMASK, xs, ys);
return 0;
}
}
if (ps > pe) /* make sel_start <= sel_end */
{
int tmp = ps;
ps = pe;
pe = tmp;
}
if (sel_cons != vc_cons[fg_console].d) {
clear_selection();
sel_cons = vc_cons[fg_console].d;
}
use_unicode = kbd && kbd->kbdmode == VC_UNICODE;
switch (sel_mode)
{
case TIOCL_SELCHAR: /* character-by-character selection */
new_sel_start = ps;
new_sel_end = pe;
break;
case TIOCL_SELWORD: /* word-by-word selection */
spc = isspace(sel_pos(ps));
for (new_sel_start = ps; ; ps -= 2)
{
if ((spc && !isspace(sel_pos(ps))) ||
(!spc && !inword(sel_pos(ps))))
break;
new_sel_start = ps;
if (!(ps % vc->vc_size_row))
break;
}
spc = isspace(sel_pos(pe));
for (new_sel_end = pe; ; pe += 2)
{
if ((spc && !isspace(sel_pos(pe))) ||
(!spc && !inword(sel_pos(pe))))
break;
new_sel_end = pe;
if (!((pe + 2) % vc->vc_size_row))
break;
}
break;
case TIOCL_SELLINE: /* line-by-line selection */
new_sel_start = ps - ps % vc->vc_size_row;
new_sel_end = pe + vc->vc_size_row
- pe % vc->vc_size_row - 2;
break;
case TIOCL_SELPOINTER:
highlight_pointer(pe);
return 0;
default:
return -EINVAL;
}
/* remove the pointer */
highlight_pointer(-1);
/* select to end of line if on trailing space */
if (new_sel_end > new_sel_start &&
!atedge(new_sel_end, vc->vc_size_row) &&
isspace(sel_pos(new_sel_end))) {
for (pe = new_sel_end + 2; ; pe += 2)
if (!isspace(sel_pos(pe)) ||
atedge(pe, vc->vc_size_row))
break;
if (isspace(sel_pos(pe)))
new_sel_end = pe;
}
if (sel_start == -1) /* no current selection */
highlight(new_sel_start, new_sel_end);
else if (new_sel_start == sel_start)
{
if (new_sel_end == sel_end) /* no action required */
return 0;
else if (new_sel_end > sel_end) /* extend to right */
highlight(sel_end + 2, new_sel_end);
else /* contract from right */
highlight(new_sel_end + 2, sel_end);
}
else if (new_sel_end == sel_end)
{
if (new_sel_start < sel_start) /* extend to left */
highlight(new_sel_start, sel_start - 2);
else /* contract from left */
highlight(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;
/* Allocate a new buffer before freeing the old one ... */
multiplier = use_unicode ? 3 : 1; /* chars can take up to 3 bytes */
bp = kmalloc(((sel_end-sel_start)/2+1)*multiplier, GFP_KERNEL);
if (!bp) {
printk(KERN_WARNING "selection: kmalloc() failed\n");
clear_selection();
return -ENOMEM;
}
kfree(sel_buffer);
sel_buffer = bp;
obp = bp;
for (i = sel_start; i <= sel_end; i += 2) {
c = sel_pos(i);
if (use_unicode)
bp += store_utf8(c, bp);
else
*bp++ = c;
if (!isspace(c))
obp = bp;
if (! ((i + 2) % vc->vc_size_row)) {
/* strip trailing blanks from line and add newline,
unless non-space at end of line. */
if (obp != bp) {
bp = obp;
*bp++ = '\r';
}
obp = bp;
}
}
sel_buffer_lth = bp - sel_buffer;
return 0;
}
/* Insert the contents of the selection buffer into the
* queue of the tty associated with the current console.
* Invoked by ioctl().
*/
int paste_selection(struct tty_struct *tty)
{
struct vc_data *vc = tty->driver_data;
int pasted = 0;
unsigned int count;
struct tty_ldisc *ld;
DECLARE_WAITQUEUE(wait, current);
acquire_console_sem();
poke_blanked_console();
release_console_sem();
ld = tty_ldisc_ref_wait(tty);
add_wait_queue(&vc->paste_wait, &wait);
while (sel_buffer && sel_buffer_lth > pasted) {
set_current_state(TASK_INTERRUPTIBLE);
if (test_bit(TTY_THROTTLED, &tty->flags)) {
schedule();
continue;
}
count = sel_buffer_lth - pasted;
count = min(count, tty->receive_room);
tty->ldisc->ops->receive_buf(tty, sel_buffer + pasted,
NULL, count);
pasted += count;
}
remove_wait_queue(&vc->paste_wait, &wait);
__set_current_state(TASK_RUNNING);
tty_ldisc_deref(ld);
return 0;
}
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...