lib/genalloc: fix the overflow when size is too big
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>
parent
aa8c7db4