eCryptfs lower file handling code has several issues:
- Retval from prepare_write()/commit_writ() was't checked to equality
to AOP_TRUNCATED_PAGE.
- In some places page was't unmapped and unlocked after error.
Signed-off-by: Dmitriy Monakhov <[EMAIL PROTECTED]>
--------------
diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c
index 06843d2..27ac9ef 100644
--- a/fs/ecryptfs/mmap.c
+++ b/fs/ecryptfs/mmap.c
@@ -391,12 +391,14 @@ out:
return rc;
}
-static void ecryptfs_unmap_and_release_lower_page(struct page *lower_page)
+static void ecryptfs_unmap_and_release_lower_page(struct page *lower_page,
+ int page_locked)
{
kunmap(lower_page);
ecryptfs_printk(KERN_DEBUG, "Unlocking lower page with index = "
"[0x%.16x]\n", lower_page->index);
- unlock_page(lower_page);
+ if (page_locked)
+ unlock_page(lower_page);
page_cache_release(lower_page);
}
@@ -417,6 +419,7 @@ ecryptfs_write_inode_size_to_header(struct file *lower_file,
char *header_virt;
const struct address_space_operations *lower_a_ops;
u64 file_size;
+ int pg_locked = 1;
rc = ecryptfs_grab_and_map_lower_page(&header_page, &header_virt,
lower_inode, 0);
@@ -427,6 +430,12 @@ 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)
+ pg_locked = 0;
+ ecryptfs_unmap_and_release_lower_page(header_page, pg_locked);
+ 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);
@@ -435,7 +444,9 @@ ecryptfs_write_inode_size_to_header(struct file *lower_file,
if (rc < 0)
ecryptfs_printk(KERN_ERR, "Error commiting header page "
"write\n");
- ecryptfs_unmap_and_release_lower_page(header_page);
+ if (rc == AOP_TRUNCATED_PAGE)
+ pg_locked = 0;
+ ecryptfs_unmap_and_release_lower_page(header_page, pg_locked);
lower_inode->i_mtime = lower_inode->i_ctime = CURRENT_TIME;
mark_inode_dirty_sync(inode);
out:
@@ -468,7 +479,10 @@ int ecryptfs_get_lower_page(struct page **lower_page,
struct inode *lower_inode,
}
out:
if (rc && (*lower_page)) {
- ecryptfs_unmap_and_release_lower_page(*lower_page);
+ int pg_locked = 1;
+ if (rc == AOP_TRUNCATED_PAGE)
+ pg_locked = 0;
+ ecryptfs_unmap_and_release_lower_page(*lower_page, pg_locked);
(*lower_page) = NULL;
}
return rc;
@@ -484,16 +498,19 @@ ecryptfs_commit_lower_page(struct page *lower_page,
struct inode *lower_inode,
struct file *lower_file, int byte_offset,
int region_size)
{
+ int pg_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)
+ pg_locked = 0;
if (rc < 0) {
ecryptfs_printk(KERN_ERR,
"Error committing write; rc = [%d]\n", rc);
} else
rc = 0;
- ecryptfs_unmap_and_release_lower_page(lower_page);
+ ecryptfs_unmap_and_release_lower_page(lower_page, pg_locked);
return rc;
}
@@ -541,6 +558,7 @@ process_new_file(struct ecryptfs_crypt_stat *crypt_stat,
int current_header_page = 0;
int header_pages;
int more_header_data_to_be_written = 1;
+ int pg_locked = 1;
lower_inode = ecryptfs_inode_to_lower(inode);
lower_file = ecryptfs_file_to_lower(file);
@@ -563,6 +581,10 @@ process_new_file(struct ecryptfs_crypt_stat *crypt_stat,
rc = lower_a_ops->prepare_write(lower_file, header_page, 0,
PAGE_CACHE_SIZE);
if (rc) {
+ if (rc == AOP_TRUNCATED_PAGE)
+ pg_locked = 0;
+ ecryptfs_unmap_and_release_lower_page(header_page,
+ pg_locked);
ecryptfs_printk(KERN_ERR, "Error preparing to write "
"header page out; rc = [%d]\n", rc);
goto out;
@@ -579,7 +601,7 @@ process_new_file(struct ecryptfs_crypt_stat *crypt_stat,
rc = -EIO;
memset(header_virt, 0, PAGE_CACHE_SIZE);
ecryptfs_unmap_and_release_lower_page(
- header_page);
+ header_page, pg_locked);
goto out;
}
if (current_header_page == 0)
@@ -588,7 +610,9 @@ process_new_file(struct ecryptfs_crypt_stat *crypt_stat,
}
rc = lower_a_ops->commit_write(lower_file, header_page, 0,
PAGE_CACHE_SIZE);
- ecryptfs_unmap_and_release_lower_page(header_page);
+ if (rc == AOP_TRUNCATED_PAGE)
+ pg_locked = 0;
+ ecryptfs_unmap_and_release_lower_page(header_page, pg_locked);
if (rc < 0) {
ecryptfs_printk(KERN_ERR,
"Error commiting header page write; "
