From: Huang Shijie sjhuang@iluvatar.ai
[ 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 --- lib/genalloc.c | 25 +++++++++++++------------ 1 file changed, 13 insertions(+), 12 deletions(-)
diff --git a/lib/genalloc.c b/lib/genalloc.c index e3a475b14e260..b8ac0450a2a68 100644 --- a/lib/genalloc.c +++ b/lib/genalloc.c @@ -83,14 +83,14 @@ 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; @@ -118,14 +118,15 @@ 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; @@ -184,8 +185,8 @@ int gen_pool_add_virt(struct gen_pool *pool, unsigned long virt, phys_addr_t phy size_t size, int nid) { 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); @@ -274,7 +275,7 @@ unsigned long gen_pool_alloc(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()); @@ -357,7 +358,7 @@ void gen_pool_free(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()); @@ -553,7 +554,7 @@ 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;