diff options
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/drm/Kconfig | 2 | ||||
| -rw-r--r-- | drivers/char/random.c | 67 |
2 files changed, 39 insertions, 30 deletions
diff --git a/drivers/char/drm/Kconfig b/drivers/char/drm/Kconfig index ef833a1c27eb..0b7ffa5191c6 100644 --- a/drivers/char/drm/Kconfig +++ b/drivers/char/drm/Kconfig @@ -6,7 +6,7 @@ # config DRM tristate "Direct Rendering Manager (XFree86 4.1.0 and higher DRI support)" - depends on (AGP || AGP=n) && PCI + depends on (AGP || AGP=n) && PCI && !EMULATED_CMPXCHG help Kernel-level support for the Direct Rendering Infrastructure (DRI) introduced in XFree86 4.0. If you say Y here, you need to select diff --git a/drivers/char/random.c b/drivers/char/random.c index 46c1b97748b6..0474cac4a84e 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -760,7 +760,7 @@ static size_t account(struct entropy_store *r, size_t nbytes, int min, static void extract_buf(struct entropy_store *r, __u8 *out) { - int i, x; + int i; __u32 data[16], buf[5 + SHA_WORKSPACE_WORDS]; sha_init(buf); @@ -772,9 +772,11 @@ static void extract_buf(struct entropy_store *r, __u8 *out) * attempts to find previous ouputs), unless the hash * function can be inverted. */ - for (i = 0, x = 0; i < r->poolinfo->poolwords; i += 16, x+=2) { - sha_transform(buf, (__u8 *)r->pool+i, buf + 5); - add_entropy_words(r, &buf[x % 5], 1); + for (i = 0; i < r->poolinfo->poolwords; i += 16) { + /* hash blocks of 16 words = 512 bits */ + sha_transform(buf, (__u8 *)(r->pool + i), buf + 5); + /* feed back portion of the resulting hash */ + add_entropy_words(r, &buf[i % 5], 1); } /* @@ -782,7 +784,7 @@ static void extract_buf(struct entropy_store *r, __u8 *out) * portion of the pool while mixing, and hash one * final time. */ - __add_entropy_words(r, &buf[x % 5], 1, data); + __add_entropy_words(r, &buf[i % 5], 1, data); sha_transform(buf, (__u8 *)data, buf + 5); /* @@ -1018,37 +1020,44 @@ random_poll(struct file *file, poll_table * wait) return mask; } -static ssize_t -random_write(struct file * file, const char __user * buffer, - size_t count, loff_t *ppos) +static int +write_pool(struct entropy_store *r, const char __user *buffer, size_t count) { - int ret = 0; size_t bytes; __u32 buf[16]; const char __user *p = buffer; - size_t c = count; - while (c > 0) { - bytes = min(c, sizeof(buf)); + while (count > 0) { + bytes = min(count, sizeof(buf)); + if (copy_from_user(&buf, p, bytes)) + return -EFAULT; - bytes -= copy_from_user(&buf, p, bytes); - if (!bytes) { - ret = -EFAULT; - break; - } - c -= bytes; + count -= bytes; p += bytes; - add_entropy_words(&input_pool, buf, (bytes + 3) / 4); - } - if (p == buffer) { - return (ssize_t)ret; - } else { - struct inode *inode = file->f_path.dentry->d_inode; - inode->i_mtime = current_fs_time(inode->i_sb); - mark_inode_dirty(inode); - return (ssize_t)(p - buffer); + add_entropy_words(r, buf, (bytes + 3) / 4); } + + return 0; +} + +static ssize_t +random_write(struct file * file, const char __user * buffer, + size_t count, loff_t *ppos) +{ + size_t ret; + struct inode *inode = file->f_path.dentry->d_inode; + + ret = write_pool(&blocking_pool, buffer, count); + if (ret) + return ret; + ret = write_pool(&nonblocking_pool, buffer, count); + if (ret) + return ret; + + inode->i_mtime = current_fs_time(inode->i_sb); + mark_inode_dirty(inode); + return (ssize_t)count; } static int @@ -1087,8 +1096,8 @@ random_ioctl(struct inode * inode, struct file * file, return -EINVAL; if (get_user(size, p++)) return -EFAULT; - retval = random_write(file, (const char __user *) p, - size, &file->f_pos); + retval = write_pool(&input_pool, (const char __user *)p, + size); if (retval < 0) return retval; credit_entropy_store(&input_pool, ent_count); |