Commit ca9ce8f2 authored by Paul Eggert's avatar Paul Eggert

Integer and memory overflow fixes for display code.

* dispextern.h (struct glyph_pool.nglyphs): Now ptrdiff_t, not int.
* dispnew.c (adjust_glyph_matrix, realloc_glyph_pool, scrolling_window):
Check for overflow in size calculations.
(line_draw_cost, realloc_glyph_pool, add_row_entry):
Don't assume glyph table len fits in int.
(struct row_entry.bucket, row_entry_pool_size, row_entry_idx)
(row_table_size): Now ptrdiff_t, not int.
(scrolling_window): Avoid overflow in size calculations.
Don't update size until allocation succeeds.
* fns.c (concat): Check for overflow in size calculations.
(next_almost_prime): Verify NEXT_ALMOST_PRIME_LIMIT.
* lisp.h (RANGED_INTEGERP, TYPE_RANGED_INTEGERP): New macros.
(NEXT_ALMOST_PRIME_LIMIT): New constant.
parent 7bd42522
2011-07-28 Paul Eggert <eggert@cs.ucla.edu>
Integer and memory overflow fixes for display code.
* dispextern.h (struct glyph_pool.nglyphs): Now ptrdiff_t, not int.
* dispnew.c (adjust_glyph_matrix, realloc_glyph_pool, scrolling_window):
Check for overflow in size calculations.
(line_draw_cost, realloc_glyph_pool, add_row_entry):
Don't assume glyph table len fits in int.
(struct row_entry.bucket, row_entry_pool_size, row_entry_idx)
(row_table_size): Now ptrdiff_t, not int.
(scrolling_window): Avoid overflow in size calculations.
Don't update size until allocation succeeds.
* fns.c (concat): Check for overflow in size calculations.
(next_almost_prime): Verify NEXT_ALMOST_PRIME_LIMIT.
* lisp.h (RANGED_INTEGERP, TYPE_RANGED_INTEGERP): New macros.
(NEXT_ALMOST_PRIME_LIMIT): New constant.
* composite.c: Integer overflow fixes.
(get_composition_id): Check for overflow in glyph length calculations.
......
......@@ -575,7 +575,7 @@ struct glyph_pool
struct glyph *glyphs;
/* Allocated size of `glyphs'. */
int nglyphs;
ptrdiff_t nglyphs;
/* Number of rows and columns in a matrix. */
int nrows, ncolumns;
......
......@@ -499,7 +499,10 @@ adjust_glyph_matrix (struct window *w, struct glyph_matrix *matrix, int x, int y
/* Enlarge MATRIX->rows if necessary. New rows are cleared. */
if (matrix->rows_allocated < dim.height)
{
ptrdiff_t size = dim.height * sizeof (struct glyph_row);
ptrdiff_t size;
if (min (PTRDIFF_MAX, SIZE_MAX) / sizeof (struct glyph_row) < dim.height)
memory_full (SIZE_MAX);
size = dim.height * sizeof (struct glyph_row);
new_rows = dim.height - matrix->rows_allocated;
matrix->rows = (struct glyph_row *) xrealloc (matrix->rows, size);
memset (matrix->rows + matrix->rows_allocated, 0,
......@@ -573,6 +576,9 @@ adjust_glyph_matrix (struct window *w, struct glyph_matrix *matrix, int x, int y
struct glyph_row *row = matrix->rows;
struct glyph_row *end = row + matrix->rows_allocated;
if (min (PTRDIFF_MAX, SIZE_MAX) / sizeof (struct glyph) < dim.width)
memory_full (SIZE_MAX);
while (row < end)
{
row->glyphs[LEFT_MARGIN_AREA]
......@@ -1217,7 +1223,7 @@ line_draw_cost (struct glyph_matrix *matrix, int vpos)
struct glyph *end = beg + row->used[TEXT_AREA];
int len;
Lisp_Object *glyph_table_base = GLYPH_TABLE_BASE;
int glyph_table_len = GLYPH_TABLE_LENGTH;
ptrdiff_t glyph_table_len = GLYPH_TABLE_LENGTH;
/* Ignore trailing and leading spaces if we can. */
if (!FRAME_MUST_WRITE_SPACES (SELECTED_FRAME ())) /* XXX Is SELECTED_FRAME OK here? */
......@@ -1391,31 +1397,26 @@ free_glyph_pool (struct glyph_pool *pool)
static int
realloc_glyph_pool (struct glyph_pool *pool, struct dim matrix_dim)
{
int needed;
ptrdiff_t needed;
int changed_p;
changed_p = (pool->glyphs == 0
|| matrix_dim.height != pool->nrows
|| matrix_dim.width != pool->ncolumns);
if (min (PTRDIFF_MAX, SIZE_MAX) / sizeof (struct glyph) / matrix_dim.width
< matrix_dim.height)
memory_full (SIZE_MAX);
/* Enlarge the glyph pool. */
needed = matrix_dim.width * matrix_dim.height;
needed = matrix_dim.width;
needed *= matrix_dim.height;
if (needed > pool->nglyphs)
{
ptrdiff_t size = needed * sizeof (struct glyph);
if (pool->glyphs)
{
pool->glyphs = (struct glyph *) xrealloc (pool->glyphs, size);
memset (pool->glyphs + pool->nglyphs, 0,
size - pool->nglyphs * sizeof (struct glyph));
}
else
{
pool->glyphs = (struct glyph *) xmalloc (size);
memset (pool->glyphs, 0, size);
}
pool->glyphs = (struct glyph *) xrealloc (pool->glyphs, size);
memset (pool->glyphs + pool->nglyphs, 0,
size - pool->nglyphs * sizeof (struct glyph));
pool->nglyphs = needed;
}
......@@ -4166,7 +4167,7 @@ struct row_entry
int new_line_number;
/* Bucket index of this row_entry in the hash table row_table. */
int bucket;
ptrdiff_t bucket;
/* The row described by this entry. */
struct glyph_row *row;
......@@ -4180,18 +4181,18 @@ struct row_entry
that we need a larger one. */
static struct row_entry *row_entry_pool;
static int row_entry_pool_size;
static ptrdiff_t row_entry_pool_size;
/* Index of next free entry in row_entry_pool. */
static int row_entry_idx;
static ptrdiff_t row_entry_idx;
/* The hash table used during scrolling, and the table's size. This
table is used to quickly identify equal rows in the desired and
current matrix. */
static struct row_entry **row_table;
static int row_table_size;
static ptrdiff_t row_table_size;
/* Vectors of pointers to row_entry structures belonging to the
current and desired matrix, and the size of the vectors. */
......@@ -4214,7 +4215,7 @@ static inline struct row_entry *
add_row_entry (struct glyph_row *row)
{
struct row_entry *entry;
int i = row->hash % row_table_size;
ptrdiff_t i = row->hash % row_table_size;
entry = row_table[i];
while (entry && !row_equal_p (entry->row, row, 1))
......@@ -4267,9 +4268,10 @@ scrolling_window (struct window *w, int header_line_p)
struct glyph_matrix *desired_matrix = w->desired_matrix;
struct glyph_matrix *current_matrix = w->current_matrix;
int yb = window_text_bottom_y (w);
int i, j, first_old, first_new, last_old, last_new;
int nruns, n, run_idx;
ptrdiff_t nbytes;
ptrdiff_t i;
int j, first_old, first_new, last_old, last_new;
int nruns, run_idx;
ptrdiff_t n, nbytes;
struct row_entry *entry;
struct redisplay_interface *rif = FRAME_RIF (XFRAME (WINDOW_FRAME (w)));
......@@ -4354,45 +4356,77 @@ scrolling_window (struct window *w, int header_line_p)
if (last_new == first_new)
return 0;
/* Check for integer overflow in xrealloc size calculation.
If next_almost_prime checks (N) for divisibility by 2..10, then
it can return at most N + 10, e.g., next_almost_prime (1) == 11.
So, set next_almost_prime_increment_max to 10.
It's just a coincidence that next_almost_prime_increment_max ==
NEXT_ALMOST_PRIME_LIMIT - 1. If NEXT_ALMOST_PRIME_LIMIT were
13, then next_almost_prime_increment_max would be 14, e.g.,
because next_almost_prime (113) would be 127. */
{
verify (NEXT_ALMOST_PRIME_LIMIT == 11);
enum { next_almost_prime_increment_max = 10 };
ptrdiff_t alloc_max = min (PTRDIFF_MAX, SIZE_MAX);
ptrdiff_t row_table_max =
((alloc_max - next_almost_prime_increment_max)
/ (3 * sizeof *row_table));
ptrdiff_t row_entry_pool_max = alloc_max / sizeof *row_entry_pool;
int n_max = min (INT_MAX, min (row_table_max, row_entry_pool_max));
ptrdiff_t old_lines_max = alloc_max / sizeof *old_lines;
int current_nrows_max = min (n_max - desired_matrix->nrows, old_lines_max);
int desired_nrows_max =
min (INT_MAX,
alloc_max / max (sizeof *new_lines,
max (sizeof *runs, sizeof *run_pool)));
if (current_nrows_max < current_matrix->nrows
|| desired_nrows_max < desired_matrix->nrows)
memory_full (SIZE_MAX);
}
/* Reallocate vectors, tables etc. if necessary. */
if (current_matrix->nrows > old_lines_size)
{
old_lines_size = current_matrix->nrows;
nbytes = old_lines_size * sizeof *old_lines;
nbytes = current_matrix->nrows * sizeof *old_lines;
old_lines = (struct row_entry **) xrealloc (old_lines, nbytes);
old_lines_size = current_matrix->nrows;
}
if (desired_matrix->nrows > new_lines_size)
{
new_lines_size = desired_matrix->nrows;
nbytes = new_lines_size * sizeof *new_lines;
nbytes = desired_matrix->nrows * sizeof *new_lines;
new_lines = (struct row_entry **) xrealloc (new_lines, nbytes);
new_lines_size = desired_matrix->nrows;
}
n = desired_matrix->nrows + current_matrix->nrows;
if (3 * n > row_table_size)
n = desired_matrix->nrows;
n += current_matrix->nrows;
if (row_table_size / 3 < n)
{
row_table_size = next_almost_prime (3 * n);
nbytes = row_table_size * sizeof *row_table;
ptrdiff_t size = next_almost_prime (3 * n);
nbytes = size * sizeof *row_table;
row_table = (struct row_entry **) xrealloc (row_table, nbytes);
row_table_size = size;
memset (row_table, 0, nbytes);
}
if (n > row_entry_pool_size)
{
row_entry_pool_size = n;
nbytes = row_entry_pool_size * sizeof *row_entry_pool;
nbytes = n * sizeof *row_entry_pool;
row_entry_pool = (struct row_entry *) xrealloc (row_entry_pool, nbytes);
row_entry_pool_size = n;
}
if (desired_matrix->nrows > runs_size)
{
runs_size = desired_matrix->nrows;
nbytes = runs_size * sizeof *runs;
nbytes = desired_matrix->nrows * sizeof *runs;
runs = (struct run **) xrealloc (runs, nbytes);
nbytes = runs_size * sizeof *run_pool;
nbytes = desired_matrix->nrows * sizeof *run_pool;
run_pool = (struct run *) xrealloc (run_pool, nbytes);
runs_size = desired_matrix->nrows;
}
nruns = run_idx = 0;
......
......@@ -602,7 +602,12 @@ concat (ptrdiff_t nargs, Lisp_Object *args,
prev = Qnil;
if (STRINGP (val))
SAFE_ALLOCA (textprops, struct textprop_rec *, sizeof (struct textprop_rec) * nargs);
{
if (min (PTRDIFF_MAX, SIZE_MAX) / sizeof *textprops < nargs)
memory_full (SIZE_MAX);
SAFE_ALLOCA (textprops, struct textprop_rec *,
sizeof *textprops * nargs);
}
for (argnum = 0; argnum < nargs; argnum++)
{
......@@ -3395,11 +3400,13 @@ check_hash_table (Lisp_Object obj)
/* Value is the next integer I >= N, N >= 0 which is "almost" a prime
number. */
number. A number is "almost" a prime number if it is not divisible
by any integer in the range 2 .. (NEXT_ALMOST_PRIME_LIMIT - 1). */
EMACS_INT
next_almost_prime (EMACS_INT n)
{
verify (NEXT_ALMOST_PRIME_LIMIT == 11);
for (n |= 1; ; n += 2)
if (n % 3 != 0 && n % 5 != 0 && n % 7 != 0)
return n;
......
......@@ -1704,6 +1704,11 @@ typedef struct {
#define NUMBERP(x) (INTEGERP (x) || FLOATP (x))
#define NATNUMP(x) (INTEGERP (x) && XINT (x) >= 0)
#define RANGED_INTEGERP(lo, x, hi) \
(INTEGERP (x) && (lo) <= XINT (x) && XINT (x) <= (hi))
#define TYPE_RANGED_INTEGERP(type, x) \
RANGED_INTEGERP (TYPE_MINIMUM (type), x, TYPE_MAXIMUM (type))
#define INTEGERP(x) (LISP_INT_TAG_P (XTYPE ((x))))
#define SYMBOLP(x) (XTYPE ((x)) == Lisp_Symbol)
#define MISCP(x) (XTYPE ((x)) == Lisp_Misc)
......@@ -2551,6 +2556,7 @@ extern void syms_of_syntax (void);
/* Defined in fns.c */
extern Lisp_Object QCrehash_size, QCrehash_threshold;
enum { NEXT_ALMOST_PRIME_LIMIT = 11 };
extern EMACS_INT next_almost_prime (EMACS_INT);
extern Lisp_Object larger_vector (Lisp_Object, EMACS_INT, Lisp_Object);
extern void sweep_weak_hash_tables (void);
......
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