diff options
Diffstat (limited to 'drivers/char')
-rw-r--r-- | drivers/char/mem.c | 2 | ||||
-rw-r--r-- | drivers/char/random.c | 26 |
2 files changed, 26 insertions, 2 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 0975d23031ea..2898d19fadf5 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -346,7 +346,7 @@ static int mmap_mem(struct file *file, struct vm_area_struct *vma) phys_addr_t offset = (phys_addr_t)vma->vm_pgoff << PAGE_SHIFT; /* It's illegal to wrap around the end of the physical address space. */ - if (offset + (phys_addr_t)size < offset) + if (offset + (phys_addr_t)size - 1 < offset) return -EINVAL; if (!valid_mmap_phys_addr_range(vma->vm_pgoff, size)) diff --git a/drivers/char/random.c b/drivers/char/random.c index 491a4dce13fe..1822472dffab 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -1798,13 +1798,15 @@ int random_int_secret_init(void) return 0; } +static DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash) + __aligned(sizeof(unsigned long)); + /* * Get a random word for internal kernel use only. Similar to urandom but * with the goal of minimal entropy pool depletion. As a result, the random * value is not cryptographically secure but for several uses the cost of * depleting entropy is too high */ -static DEFINE_PER_CPU(__u32 [MD5_DIGEST_WORDS], get_random_int_hash); unsigned int get_random_int(void) { __u32 *hash; @@ -1825,6 +1827,28 @@ unsigned int get_random_int(void) EXPORT_SYMBOL(get_random_int); /* + * Same as get_random_int(), but returns unsigned long. + */ +unsigned long get_random_long(void) +{ + __u32 *hash; + unsigned long ret; + + if (arch_get_random_long(&ret)) + return ret; + + hash = get_cpu_var(get_random_int_hash); + + hash[0] += current->pid + jiffies + random_get_entropy(); + md5_transform(hash, random_int_secret); + ret = *(unsigned long *)hash; + put_cpu_var(get_random_int_hash); + + return ret; +} +EXPORT_SYMBOL(get_random_long); + +/* * randomize_range() returns a start address such that * * [...... <range> .....] |