diff options
| author | Li Wang <liwang@nudt.edu.cn> | 2012-01-19 09:44:36 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-02-13 11:28:49 -0800 |
| commit | e065d6f4f4453db007d4fb22ebb937e38922cb4b (patch) | |
| tree | ecab58e6a91bde84bdfc874a8838868f33d0ec71 | |
| parent | 23145ac5c650072d73beab2fee839d6129a22e72 (diff) | |
eCryptfs: Infinite loop due to overflow in ecryptfs_write()
commit 684a3ff7e69acc7c678d1a1394fe9e757993fd34 upstream.
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>
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -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 6b7854681c61..0404659755a3 100644 --- a/fs/ecryptfs/read_write.c +++ b/fs/ecryptfs/read_write.c @@ -134,7 +134,7 @@ int ecryptfs_write(struct file *ecryptfs_file, 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 (fatal_signal_pending(current)) { rc = -EINTR; @@ -145,7 +145,7 @@ int ecryptfs_write(struct file *ecryptfs_file, char *data, loff_t offset, 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; |