diff options
| author | Li Wang <liwang@nudt.edu.cn> | 2012-01-19 09:44:36 +0800 |
|---|---|---|
| committer | Tyler Hicks <tyhicks@canonical.com> | 2012-01-25 14:43:40 -0600 |
| commit | 684a3ff7e69acc7c678d1a1394fe9e757993fd34 (patch) | |
| tree | 733157a7c6ad606799fd2692f882da14aae2fd0b /fs | |
| parent | 48399c0b0e6172888a2e2e36df1595ab1e049ba8 (diff) | |
eCryptfs: Infinite loop due to overflow in ecryptfs_write()
ecryptfs_write() can enter an infinite loop when truncating a file to a
size larger than 4G. This only happens on architectures where size_t is
represented by 32 bits.
This was caused by a size_t overflow due to it incorrectly being used to
store the result of a calculation which uses potentially large values of
type loff_t.
[tyhicks@canonical.com: rewrite subject and commit message]
Signed-off-by: Li Wang <liwang@nudt.edu.cn>
Signed-off-by: Yunchuan Wen <wenyunchuan@kylinos.com.cn>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ecryptfs/read_write.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/ecryptfs/read_write.c b/fs/ecryptfs/read_write.c index 3745f7c2b9c..ec3d9368dc5 100644 --- a/fs/ecryptfs/read_write.c +++ b/fs/ecryptfs/read_write.c @@ -130,13 +130,13 @@ int ecryptfs_write(struct inode *ecryptfs_inode, char *data, loff_t offset, pgoff_t ecryptfs_page_idx = (pos >> PAGE_CACHE_SHIFT); size_t start_offset_in_page = (pos & ~PAGE_CACHE_MASK); size_t num_bytes = (PAGE_CACHE_SIZE - start_offset_in_page); - size_t total_remaining_bytes = ((offset + size) - pos); + loff_t total_remaining_bytes = ((offset + size) - pos); if (num_bytes > total_remaining_bytes) num_bytes = total_remaining_bytes; if (pos < offset) { /* remaining zeros to write, up to destination offset */ - size_t total_remaining_zeros = (offset - pos); + loff_t total_remaining_zeros = (offset - pos); if (num_bytes > total_remaining_zeros) num_bytes = total_remaining_zeros; |