diff options
author | Li Wang <liwang@nudt.edu.cn> | 2012-01-18 20:44:36 -0500 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-02-13 14:06:09 -0500 |
commit | 1a11d5d7fb7988a92e798dfbed7cdd350c0701cc (patch) | |
tree | 252c858c9b52ba6a819d8d27ce36af0dbbc861b2 /fs | |
parent | dade9ad146b19c22141032d84190d2220623d2ca (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>
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 54eb14caad7..608c1c3fde1 100644 --- a/fs/ecryptfs/read_write.c +++ b/fs/ecryptfs/read_write.c | |||
@@ -130,7 +130,7 @@ int ecryptfs_write(struct inode *ecryptfs_inode, char *data, loff_t offset, | |||
130 | pgoff_t ecryptfs_page_idx = (pos >> PAGE_CACHE_SHIFT); | 130 | pgoff_t ecryptfs_page_idx = (pos >> PAGE_CACHE_SHIFT); |
131 | size_t start_offset_in_page = (pos & ~PAGE_CACHE_MASK); | 131 | size_t start_offset_in_page = (pos & ~PAGE_CACHE_MASK); |
132 | size_t num_bytes = (PAGE_CACHE_SIZE - start_offset_in_page); | 132 | size_t num_bytes = (PAGE_CACHE_SIZE - start_offset_in_page); |
133 | size_t total_remaining_bytes = ((offset + size) - pos); | 133 | loff_t total_remaining_bytes = ((offset + size) - pos); |
134 | 134 | ||
135 | if (fatal_signal_pending(current)) { | 135 | if (fatal_signal_pending(current)) { |
136 | rc = -EINTR; | 136 | rc = -EINTR; |
@@ -141,7 +141,7 @@ int ecryptfs_write(struct inode *ecryptfs_inode, char *data, loff_t offset, | |||
141 | num_bytes = total_remaining_bytes; | 141 | num_bytes = total_remaining_bytes; |
142 | if (pos < offset) { | 142 | if (pos < offset) { |
143 | /* remaining zeros to write, up to destination offset */ | 143 | /* remaining zeros to write, up to destination offset */ |
144 | size_t total_remaining_zeros = (offset - pos); | 144 | loff_t total_remaining_zeros = (offset - pos); |
145 | 145 | ||
146 | if (num_bytes > total_remaining_zeros) | 146 | if (num_bytes > total_remaining_zeros) |
147 | num_bytes = total_remaining_zeros; | 147 | num_bytes = total_remaining_zeros; |