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Diffstat (limited to 'fs/ecryptfs/mmap.c')
-rw-r--r--fs/ecryptfs/mmap.c137
1 files changed, 71 insertions, 66 deletions
diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c
index df4ce99d059..564a1fa34b9 100644
--- a/fs/ecryptfs/mmap.c
+++ b/fs/ecryptfs/mmap.c
@@ -32,6 +32,7 @@
#include <linux/file.h>
#include <linux/crypto.h>
#include <linux/scatterlist.h>
+#include <linux/slab.h>
#include <asm/unaligned.h>
#include "ecryptfs_kernel.h"
@@ -43,17 +44,9 @@
* Returns locked and up-to-date page (if ok), with increased
* refcnt.
*/
-struct page *ecryptfs_get_locked_page(struct file *file, loff_t index)
+struct page *ecryptfs_get_locked_page(struct inode *inode, loff_t index)
{
- struct dentry *dentry;
- struct inode *inode;
- struct address_space *mapping;
- struct page *page;
-
- dentry = file->f_path.dentry;
- inode = dentry->d_inode;
- mapping = inode->i_mapping;
- page = read_mapping_page(mapping, index, (void *)file);
+ struct page *page = read_mapping_page(inode->i_mapping, index, NULL);
if (!IS_ERR(page))
lock_page(page);
return page;
@@ -64,6 +57,10 @@ struct page *ecryptfs_get_locked_page(struct file *file, loff_t index)
* @page: Page that is locked before this call is made
*
* Returns zero on success; non-zero otherwise
+ *
+ * This is where we encrypt the data and pass the encrypted data to
+ * the lower filesystem. In OpenPGP-compatible mode, we operate on
+ * entire underlying packets.
*/
static int ecryptfs_writepage(struct page *page, struct writeback_control *wbc)
{
@@ -72,16 +69,29 @@ static int ecryptfs_writepage(struct page *page, struct writeback_control *wbc)
rc = ecryptfs_encrypt_page(page);
if (rc) {
ecryptfs_printk(KERN_WARNING, "Error encrypting "
- "page (upper index [0x%.16x])\n", page->index);
+ "page (upper index [0x%.16lx])\n", page->index);
ClearPageUptodate(page);
goto out;
}
SetPageUptodate(page);
- unlock_page(page);
out:
+ unlock_page(page);
return rc;
}
+static void strip_xattr_flag(char *page_virt,
+ struct ecryptfs_crypt_stat *crypt_stat)
+{
+ if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) {
+ size_t written;
+
+ crypt_stat->flags &= ~ECRYPTFS_METADATA_IN_XATTR;
+ ecryptfs_write_crypt_stat_flags(page_virt, crypt_stat,
+ &written);
+ crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
+ }
+}
+
/**
* Header Extent:
* Octets 0-7: Unencrypted file size (big-endian)
@@ -97,19 +107,6 @@ out:
* (big-endian)
* Octet 26: Begin RFC 2440 authentication token packet set
*/
-static void set_header_info(char *page_virt,
- struct ecryptfs_crypt_stat *crypt_stat)
-{
- size_t written;
- size_t save_num_header_bytes_at_front =
- crypt_stat->num_header_bytes_at_front;
-
- crypt_stat->num_header_bytes_at_front =
- ECRYPTFS_MINIMUM_HEADER_EXTENT_SIZE;
- ecryptfs_write_header_metadata(page_virt + 20, crypt_stat, &written);
- crypt_stat->num_header_bytes_at_front =
- save_num_header_bytes_at_front;
-}
/**
* ecryptfs_copy_up_encrypted_with_header
@@ -135,22 +132,26 @@ ecryptfs_copy_up_encrypted_with_header(struct page *page,
* num_extents_per_page)
+ extent_num_in_page);
size_t num_header_extents_at_front =
- (crypt_stat->num_header_bytes_at_front
- / crypt_stat->extent_size);
+ (crypt_stat->metadata_size / crypt_stat->extent_size);
if (view_extent_num < num_header_extents_at_front) {
/* This is a header extent */
char *page_virt;
- page_virt = kmap_atomic(page, KM_USER0);
+ page_virt = kmap_atomic(page);
memset(page_virt, 0, PAGE_CACHE_SIZE);
/* TODO: Support more than one header extent */
if (view_extent_num == 0) {
+ size_t written;
+
rc = ecryptfs_read_xattr_region(
page_virt, page->mapping->host);
- set_header_info(page_virt, crypt_stat);
+ strip_xattr_flag(page_virt + 16, crypt_stat);
+ ecryptfs_write_header_metadata(page_virt + 20,
+ crypt_stat,
+ &written);
}
- kunmap_atomic(page_virt, KM_USER0);
+ kunmap_atomic(page_virt);
flush_dcache_page(page);
if (rc) {
printk(KERN_ERR "%s: Error reading xattr "
@@ -161,7 +162,7 @@ ecryptfs_copy_up_encrypted_with_header(struct page *page,
/* This is an encrypted data extent */
loff_t lower_offset =
((view_extent_num * crypt_stat->extent_size)
- - crypt_stat->num_header_bytes_at_front);
+ - crypt_stat->metadata_size);
rc = ecryptfs_read_lower_page_segment(
page, (lower_offset >> PAGE_CACHE_SHIFT),
@@ -193,14 +194,10 @@ out:
static int ecryptfs_readpage(struct file *file, struct page *page)
{
struct ecryptfs_crypt_stat *crypt_stat =
- &ecryptfs_inode_to_private(file->f_path.dentry->d_inode)->crypt_stat;
+ &ecryptfs_inode_to_private(page->mapping->host)->crypt_stat;
int rc = 0;
- if (!crypt_stat
- || !(crypt_stat->flags & ECRYPTFS_ENCRYPTED)
- || (crypt_stat->flags & ECRYPTFS_NEW_FILE)) {
- ecryptfs_printk(KERN_DEBUG,
- "Passing through unencrypted page\n");
+ if (!crypt_stat || !(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
rc = ecryptfs_read_lower_page_segment(page, page->index, 0,
PAGE_CACHE_SIZE,
page->mapping->host);
@@ -240,7 +237,7 @@ out:
ClearPageUptodate(page);
else
SetPageUptodate(page);
- ecryptfs_printk(KERN_DEBUG, "Unlocking page with index = [0x%.16x]\n",
+ ecryptfs_printk(KERN_DEBUG, "Unlocking page with index = [0x%.16lx]\n",
page->index);
unlock_page(page);
return rc;
@@ -293,13 +290,12 @@ static int ecryptfs_write_begin(struct file *file,
return -ENOMEM;
*pagep = page;
+ prev_page_end_size = ((loff_t)index << PAGE_CACHE_SHIFT);
if (!PageUptodate(page)) {
struct ecryptfs_crypt_stat *crypt_stat =
- &ecryptfs_inode_to_private(
- file->f_path.dentry->d_inode)->crypt_stat;
+ &ecryptfs_inode_to_private(mapping->host)->crypt_stat;
- if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)
- || (crypt_stat->flags & ECRYPTFS_NEW_FILE)) {
+ if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
rc = ecryptfs_read_lower_page_segment(
page, index, 0, PAGE_CACHE_SIZE, mapping->host);
if (rc) {
@@ -339,18 +335,24 @@ static int ecryptfs_write_begin(struct file *file,
SetPageUptodate(page);
}
} else {
- rc = ecryptfs_decrypt_page(page);
- if (rc) {
- printk(KERN_ERR "%s: Error decrypting page "
- "at index [%ld]; rc = [%d]\n",
- __func__, page->index, rc);
- ClearPageUptodate(page);
- goto out;
+ if (prev_page_end_size
+ >= i_size_read(page->mapping->host)) {
+ zero_user(page, 0, PAGE_CACHE_SIZE);
+ SetPageUptodate(page);
+ } else if (len < PAGE_CACHE_SIZE) {
+ rc = ecryptfs_decrypt_page(page);
+ if (rc) {
+ printk(KERN_ERR "%s: Error decrypting "
+ "page at index [%ld]; "
+ "rc = [%d]\n",
+ __func__, page->index, rc);
+ ClearPageUptodate(page);
+ goto out;
+ }
+ SetPageUptodate(page);
}
- SetPageUptodate(page);
}
}
- prev_page_end_size = ((loff_t)index << PAGE_CACHE_SHIFT);
/* If creating a page or more of holes, zero them out via truncate.
* Note, this will increase i_size. */
if (index != 0) {
@@ -372,6 +374,11 @@ static int ecryptfs_write_begin(struct file *file,
&& (pos != 0))
zero_user(page, 0, PAGE_CACHE_SIZE);
out:
+ if (unlikely(rc)) {
+ unlock_page(page);
+ page_cache_release(page);
+ *pagep = NULL;
+ }
return rc;
}
@@ -467,10 +474,6 @@ int ecryptfs_write_inode_size_to_metadata(struct inode *ecryptfs_inode)
* @copied: The amount of data copied
* @page: The eCryptfs page
* @fsdata: The fsdata (unused)
- *
- * This is where we encrypt the data and pass the encrypted data to
- * the lower filesystem. In OpenPGP-compatible mode, we operate on
- * entire underlying packets.
*/
static int ecryptfs_write_end(struct file *file,
struct address_space *mapping,
@@ -482,17 +485,11 @@ static int ecryptfs_write_end(struct file *file,
unsigned to = from + copied;
struct inode *ecryptfs_inode = mapping->host;
struct ecryptfs_crypt_stat *crypt_stat =
- &ecryptfs_inode_to_private(file->f_path.dentry->d_inode)->crypt_stat;
+ &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
int rc;
- if (crypt_stat->flags & ECRYPTFS_NEW_FILE) {
- ecryptfs_printk(KERN_DEBUG, "ECRYPTFS_NEW_FILE flag set in "
- "crypt_stat at memory location [%p]\n", crypt_stat);
- crypt_stat->flags &= ~(ECRYPTFS_NEW_FILE);
- } else
- ecryptfs_printk(KERN_DEBUG, "Not a new file\n");
ecryptfs_printk(KERN_DEBUG, "Calling fill_zeros_to_end_of_page"
- "(page w/ index = [0x%.16x], to = [%d])\n", index, to);
+ "(page w/ index = [0x%.16lx], to = [%d])\n", index, to);
if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
rc = ecryptfs_write_lower_page_segment(ecryptfs_inode, page, 0,
to);
@@ -503,23 +500,31 @@ static int ecryptfs_write_end(struct file *file,
}
goto out;
}
+ if (!PageUptodate(page)) {
+ if (copied < PAGE_CACHE_SIZE) {
+ rc = 0;
+ goto out;
+ }
+ SetPageUptodate(page);
+ }
/* Fills in zeros if 'to' goes beyond inode size */
rc = fill_zeros_to_end_of_page(page, to);
if (rc) {
ecryptfs_printk(KERN_WARNING, "Error attempting to fill "
- "zeros in page with index = [0x%.16x]\n", index);
+ "zeros in page with index = [0x%.16lx]\n", index);
goto out;
}
rc = ecryptfs_encrypt_page(page);
if (rc) {
ecryptfs_printk(KERN_WARNING, "Error encrypting page (upper "
- "index [0x%.16x])\n", index);
+ "index [0x%.16lx])\n", index);
goto out;
}
if (pos + copied > i_size_read(ecryptfs_inode)) {
i_size_write(ecryptfs_inode, pos + copied);
ecryptfs_printk(KERN_DEBUG, "Expanded file size to "
- "[0x%.16x]\n", i_size_read(ecryptfs_inode));
+ "[0x%.16llx]\n",
+ (unsigned long long)i_size_read(ecryptfs_inode));
}
rc = ecryptfs_write_inode_size_to_metadata(ecryptfs_inode);
if (rc)
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 19:11:33 +0000