commit: 684a3ff7e69acc7c678d1a1394fe9e757993fd34 From: Li Wang <[email protected]> Date: Thu, 19 Jan 2012 09:44:36 +0800 Subject: 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. [[email protected]: rewrite subject and commit message] Signed-off-by: Li Wang <[email protected]> Signed-off-by: Yunchuan Wen <[email protected]> Reviewed-by: Cong Wang <[email protected]> Cc: <[email protected]> Signed-off-by: Tyler Hicks <[email protected]> --- 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 3745f7c..ec3d936 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; -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
