btrfs: tree_search, copy_to_sk: return needed size on EOVERFLOW

If an item in tree_search is too large to be stored in the given buffer, return
the needed size (including the header).

Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
This commit is contained in:
Gerhard Heift 2014-01-30 16:24:00 +01:00 коммит произвёл Chris Mason
Родитель 8f5f6178f3
Коммит 9b6e817d02
1 изменённых файлов: 15 добавлений и 9 удалений

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@ -1957,7 +1957,7 @@ static noinline int copy_to_sk(struct btrfs_root *root,
struct btrfs_path *path,
struct btrfs_key *key,
struct btrfs_ioctl_search_key *sk,
size_t buf_size,
size_t *buf_size,
char *buf,
unsigned long *sk_offset,
int *num_found)
@ -1990,7 +1990,7 @@ static noinline int copy_to_sk(struct btrfs_root *root,
if (!key_in_sk(key, sk))
continue;
if (sizeof(sh) + item_len > buf_size) {
if (sizeof(sh) + item_len > *buf_size) {
if (*num_found) {
ret = 1;
goto out;
@ -2001,11 +2001,12 @@ static noinline int copy_to_sk(struct btrfs_root *root,
* handle -EOVERFLOW
*/
*buf_size = sizeof(sh) + item_len;
item_len = 0;
ret = -EOVERFLOW;
}
if (sizeof(sh) + item_len + *sk_offset > buf_size) {
if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
ret = 1;
goto out;
}
@ -2056,7 +2057,7 @@ out:
static noinline int search_ioctl(struct inode *inode,
struct btrfs_ioctl_search_key *sk,
size_t buf_size,
size_t *buf_size,
char *buf)
{
struct btrfs_root *root;
@ -2067,8 +2068,10 @@ static noinline int search_ioctl(struct inode *inode,
int num_found = 0;
unsigned long sk_offset = 0;
if (buf_size < sizeof(struct btrfs_ioctl_search_header))
if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
*buf_size = sizeof(struct btrfs_ioctl_search_header);
return -EOVERFLOW;
}
path = btrfs_alloc_path();
if (!path)
@ -2121,9 +2124,10 @@ err:
static noinline int btrfs_ioctl_tree_search(struct file *file,
void __user *argp)
{
struct btrfs_ioctl_search_args *args;
struct inode *inode;
int ret;
struct btrfs_ioctl_search_args *args;
struct inode *inode;
int ret;
size_t buf_size;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
@ -2132,8 +2136,10 @@ static noinline int btrfs_ioctl_tree_search(struct file *file,
if (IS_ERR(args))
return PTR_ERR(args);
buf_size = sizeof(args->buf);
inode = file_inode(file);
ret = search_ioctl(inode, &args->key, sizeof(args->buf), args->buf);
ret = search_ioctl(inode, &args->key, &buf_size, args->buf);
/*
* In the origin implementation an overflow is handled by returning a