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lib/genalloc: fix the overflow when size is too big

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[ Upstream commit 36845663843fc59c5d794e3dc0641472e3e572da ]

Some graphic card has very big memory on chip, such as 32G bytes.

In the following case, it will cause overflow:

    pool = gen_pool_create(PAGE_SHIFT, NUMA_NO_NODE);
    ret = gen_pool_add(pool, 0x1000000, SZ_32G, NUMA_NO_NODE);

    va = gen_pool_alloc(pool, SZ_4G);

The overflow occurs in gen_pool_alloc_algo_owner():

		....
		size = nbits << order;
		....

The @nbits is "int" type, so it will overflow.
Then the gen_pool_avail() will return the wrong value.

This patch converts some "int" to "unsigned long", and
changes the compare code in while.

Link: https://lkml.kernel.org/r/20201229060657.3389-1-sjhuang@iluvatar.ai
Signed-off-by: Huang Shijie <sjhuang@iluvatar.ai>
Reported-by: Shi Jiasheng <jiasheng.shi@iluvatar.ai>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Huang Shijie 2020-12-29 15:14:58 -08:00 committed by Greg Kroah-Hartman
parent 19e0cf8fc4
commit 663a0bcb3f
1 changed files with 13 additions and 12 deletions
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25
lib/genalloc.c
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@ -81,14 +81,14 @@ static int clear_bits_ll(unsigned long *addr, unsigned long mask_to_clear)
* users set the same bit, one user will return remain bits, otherwise
* return 0.
*/
static int bitmap_set_ll(unsigned long *map, int start, int nr)
static int bitmap_set_ll(unsigned long *map, unsigned long start, unsigned long nr)
{
unsigned long *p = map + BIT_WORD(start);
const int size = start + nr;
const unsigned long size = start + nr;
int bits_to_set = BITS_PER_LONG - (start % BITS_PER_LONG);
unsigned long mask_to_set = BITMAP_FIRST_WORD_MASK(start);
while (nr - bits_to_set >= 0) {
while (nr >= bits_to_set) {
if (set_bits_ll(p, mask_to_set))
return nr;
nr -= bits_to_set;
@ -116,14 +116,15 @@ static int bitmap_set_ll(unsigned long *map, int start, int nr)
* users clear the same bit, one user will return remain bits,
* otherwise return 0.
*/
static int bitmap_clear_ll(unsigned long *map, int start, int nr)
static unsigned long
bitmap_clear_ll(unsigned long *map, unsigned long start, unsigned long nr)
{
unsigned long *p = map + BIT_WORD(start);
const int size = start + nr;
const unsigned long size = start + nr;
int bits_to_clear = BITS_PER_LONG - (start % BITS_PER_LONG);
unsigned long mask_to_clear = BITMAP_FIRST_WORD_MASK(start);
while (nr - bits_to_clear >= 0) {
while (nr >= bits_to_clear) {
if (clear_bits_ll(p, mask_to_clear))
return nr;
nr -= bits_to_clear;
@ -183,8 +184,8 @@ int gen_pool_add_owner(struct gen_pool *pool, unsigned long virt, phys_addr_t ph
size_t size, int nid, void *owner)
{
struct gen_pool_chunk *chunk;
int nbits = size >> pool->min_alloc_order;
int nbytes = sizeof(struct gen_pool_chunk) +
unsigned long nbits = size >> pool->min_alloc_order;
unsigned long nbytes = sizeof(struct gen_pool_chunk) +
BITS_TO_LONGS(nbits) * sizeof(long);
chunk = vzalloc_node(nbytes, nid);
@ -242,7 +243,7 @@ void gen_pool_destroy(struct gen_pool *pool)
struct list_head *_chunk, *_next_chunk;
struct gen_pool_chunk *chunk;
int order = pool->min_alloc_order;
int bit, end_bit;
unsigned long bit, end_bit;
list_for_each_safe(_chunk, _next_chunk, &pool->chunks) {
chunk = list_entry(_chunk, struct gen_pool_chunk, next_chunk);
@ -278,7 +279,7 @@ unsigned long gen_pool_alloc_algo_owner(struct gen_pool *pool, size_t size,
struct gen_pool_chunk *chunk;
unsigned long addr = 0;
int order = pool->min_alloc_order;
int nbits, start_bit, end_bit, remain;
unsigned long nbits, start_bit, end_bit, remain;
#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG
BUG_ON(in_nmi());
@ -487,7 +488,7 @@ void gen_pool_free_owner(struct gen_pool *pool, unsigned long addr, size_t size,
{
struct gen_pool_chunk *chunk;
int order = pool->min_alloc_order;
int start_bit, nbits, remain;
unsigned long start_bit, nbits, remain;
#ifndef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG
BUG_ON(in_nmi());
@ -754,7 +755,7 @@ unsigned long gen_pool_best_fit(unsigned long *map, unsigned long size,
index = bitmap_find_next_zero_area(map, size, start, nr, 0);
while (index < size) {
int next_bit = find_next_bit(map, size, index + nr);
unsigned long next_bit = find_next_bit(map, size, index + nr);
if ((next_bit - index) < len) {
len = next_bit - index;
start_bit = index;