From ae73fc093a8cae4d92e22ab8b635e3590e80785d Mon Sep 17 00:00:00 2001 From: Michael Halcrow Date: Wed, 28 Feb 2007 20:12:16 -0800 Subject: [PATCH] [PATCH] eCryptfs: resolve lower page unlocking problem eCryptfs lower file handling code has several issues: - Retval from prepare_write()/commit_write() wasn't checked to equality to AOP_TRUNCATED_PAGE. - In some places page wasn't unmapped and unlocked after error. Signed-off-by: Michael Halcrow Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/ecryptfs/mmap.c | 28 +++++++++++++++++++++++----- 1 file changed, 23 insertions(+), 5 deletions(-) diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c index 3a6f65c3f14f..82bdbed658d7 100644 --- a/fs/ecryptfs/mmap.c +++ b/fs/ecryptfs/mmap.c @@ -422,9 +422,11 @@ out: return rc; } -static void ecryptfs_release_lower_page(struct page *lower_page) +static +void ecryptfs_release_lower_page(struct page *lower_page, int page_locked) { - unlock_page(lower_page); + if (page_locked) + unlock_page(lower_page); page_cache_release(lower_page); } @@ -454,6 +456,13 @@ static int ecryptfs_write_inode_size_to_header(struct file *lower_file, } lower_a_ops = lower_inode->i_mapping->a_ops; rc = lower_a_ops->prepare_write(lower_file, header_page, 0, 8); + if (rc) { + if (rc == AOP_TRUNCATED_PAGE) + ecryptfs_release_lower_page(header_page, 0); + else + ecryptfs_release_lower_page(header_page, 1); + goto out; + } file_size = (u64)i_size_read(inode); ecryptfs_printk(KERN_DEBUG, "Writing size: [0x%.16x]\n", file_size); file_size = cpu_to_be64(file_size); @@ -465,7 +474,10 @@ static int ecryptfs_write_inode_size_to_header(struct file *lower_file, if (rc < 0) ecryptfs_printk(KERN_ERR, "Error commiting header page " "write\n"); - ecryptfs_release_lower_page(header_page); + if (rc == AOP_TRUNCATED_PAGE) + ecryptfs_release_lower_page(header_page, 0); + else + ecryptfs_release_lower_page(header_page, 1); lower_inode->i_mtime = lower_inode->i_ctime = CURRENT_TIME; mark_inode_dirty_sync(inode); out: @@ -572,7 +584,10 @@ int ecryptfs_get_lower_page(struct page **lower_page, struct inode *lower_inode, } out: if (rc && (*lower_page)) { - ecryptfs_release_lower_page(*lower_page); + if (rc == AOP_TRUNCATED_PAGE) + ecryptfs_release_lower_page(*lower_page, 0); + else + ecryptfs_release_lower_page(*lower_page, 1); (*lower_page) = NULL; } return rc; @@ -588,16 +603,19 @@ ecryptfs_commit_lower_page(struct page *lower_page, struct inode *lower_inode, struct file *lower_file, int byte_offset, int region_size) { + int page_locked = 1; int rc = 0; rc = lower_inode->i_mapping->a_ops->commit_write( lower_file, lower_page, byte_offset, region_size); + if (rc == AOP_TRUNCATED_PAGE) + page_locked = 0; if (rc < 0) { ecryptfs_printk(KERN_ERR, "Error committing write; rc = [%d]\n", rc); } else rc = 0; - ecryptfs_release_lower_page(lower_page); + ecryptfs_release_lower_page(lower_page, page_locked); return rc; } -- 2.20.1