summaryrefslogtreecommitdiff
path: root/fs/btrfs/xattr.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/btrfs/xattr.c')
-rw-r--r--fs/btrfs/xattr.c299
1 files changed, 183 insertions, 116 deletions
diff --git a/fs/btrfs/xattr.c b/fs/btrfs/xattr.c
index f141b45ce349..ab55d10bd71f 100644
--- a/fs/btrfs/xattr.c
+++ b/fs/btrfs/xattr.c
@@ -13,21 +13,24 @@
#include <linux/iversion.h>
#include <linux/sched/mm.h>
#include "ctree.h"
+#include "fs.h"
+#include "messages.h"
#include "btrfs_inode.h"
#include "transaction.h"
#include "xattr.h"
#include "disk-io.h"
#include "props.h"
#include "locking.h"
+#include "accessors.h"
+#include "dir-item.h"
-int btrfs_getxattr(struct inode *inode, const char *name,
+int btrfs_getxattr(const struct inode *inode, const char *name,
void *buffer, size_t size)
{
struct btrfs_dir_item *di;
struct btrfs_root *root = BTRFS_I(inode)->root;
- struct btrfs_path *path;
+ BTRFS_PATH_AUTO_FREE(path);
struct extent_buffer *leaf;
- int ret = 0;
unsigned long data_ptr;
path = btrfs_alloc_path();
@@ -37,26 +40,19 @@ int btrfs_getxattr(struct inode *inode, const char *name,
/* lookup the xattr by name */
di = btrfs_lookup_xattr(NULL, root, path, btrfs_ino(BTRFS_I(inode)),
name, strlen(name), 0);
- if (!di) {
- ret = -ENODATA;
- goto out;
- } else if (IS_ERR(di)) {
- ret = PTR_ERR(di);
- goto out;
- }
+ if (!di)
+ return -ENODATA;
+ if (IS_ERR(di))
+ return PTR_ERR(di);
leaf = path->nodes[0];
/* if size is 0, that means we want the size of the attr */
- if (!size) {
- ret = btrfs_dir_data_len(leaf, di);
- goto out;
- }
+ if (!size)
+ return btrfs_dir_data_len(leaf, di);
/* now get the data out of our dir_item */
- if (btrfs_dir_data_len(leaf, di) > size) {
- ret = -ERANGE;
- goto out;
- }
+ if (btrfs_dir_data_len(leaf, di) > size)
+ return -ERANGE;
/*
* The way things are packed into the leaf is like this
@@ -69,31 +65,27 @@ int btrfs_getxattr(struct inode *inode, const char *name,
btrfs_dir_name_len(leaf, di));
read_extent_buffer(leaf, buffer, data_ptr,
btrfs_dir_data_len(leaf, di));
- ret = btrfs_dir_data_len(leaf, di);
-
-out:
- btrfs_free_path(path);
- return ret;
+ return btrfs_dir_data_len(leaf, di);
}
-static int do_setxattr(struct btrfs_trans_handle *trans,
- struct inode *inode, const char *name,
- const void *value, size_t size, int flags)
+int btrfs_setxattr(struct btrfs_trans_handle *trans, struct inode *inode,
+ const char *name, const void *value, size_t size, int flags)
{
struct btrfs_dir_item *di = NULL;
struct btrfs_root *root = BTRFS_I(inode)->root;
- struct btrfs_fs_info *fs_info = root->fs_info;
- struct btrfs_path *path;
+ BTRFS_PATH_AUTO_FREE(path);
size_t name_len = strlen(name);
int ret = 0;
+ ASSERT(trans);
+
if (name_len + size > BTRFS_MAX_XATTR_SIZE(root->fs_info))
return -ENOSPC;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
- path->skip_release_on_error = 1;
+ path->skip_release_on_error = true;
if (!value) {
di = btrfs_lookup_xattr(trans, root, path,
@@ -115,7 +107,7 @@ static int do_setxattr(struct btrfs_trans_handle *trans,
* locks the inode's i_mutex before calling setxattr or removexattr.
*/
if (flags & XATTR_REPLACE) {
- ASSERT(inode_is_locked(inode));
+ btrfs_assert_inode_locked(BTRFS_I(inode));
di = btrfs_lookup_xattr(NULL, root, path,
btrfs_ino(BTRFS_I(inode)), name, name_len, 0);
if (!di)
@@ -137,15 +129,15 @@ static int do_setxattr(struct btrfs_trans_handle *trans,
* matches our target xattr, so lets check.
*/
ret = 0;
- btrfs_assert_tree_locked(path->nodes[0]);
- di = btrfs_match_dir_item_name(fs_info, path, name, name_len);
+ btrfs_assert_tree_write_locked(path->nodes[0]);
+ di = btrfs_match_dir_item_name(path, name, name_len);
if (!di && !(flags & XATTR_REPLACE)) {
ret = -ENOSPC;
goto out;
}
} else if (ret == -EEXIST) {
ret = 0;
- di = btrfs_match_dir_item_name(fs_info, path, name, name_len);
+ di = btrfs_match_dir_item_name(path, name, name_len);
ASSERT(di); /* logic error */
} else if (ret) {
goto out;
@@ -167,14 +159,13 @@ static int do_setxattr(struct btrfs_trans_handle *trans,
const int slot = path->slots[0];
struct extent_buffer *leaf = path->nodes[0];
const u16 old_data_len = btrfs_dir_data_len(leaf, di);
- const u32 item_size = btrfs_item_size_nr(leaf, slot);
+ const u32 item_size = btrfs_item_size(leaf, slot);
const u32 data_size = sizeof(*di) + name_len + size;
- struct btrfs_item *item;
unsigned long data_ptr;
char *ptr;
if (size > old_data_len) {
- if (btrfs_leaf_free_space(fs_info, leaf) <
+ if (btrfs_leaf_free_space(leaf) <
(size - old_data_len)) {
ret = -ENOSPC;
goto out;
@@ -184,27 +175,23 @@ static int do_setxattr(struct btrfs_trans_handle *trans,
if (old_data_len + name_len + sizeof(*di) == item_size) {
/* No other xattrs packed in the same leaf item. */
if (size > old_data_len)
- btrfs_extend_item(fs_info, path,
- size - old_data_len);
+ btrfs_extend_item(trans, path, size - old_data_len);
else if (size < old_data_len)
- btrfs_truncate_item(fs_info, path,
- data_size, 1);
+ btrfs_truncate_item(trans, path, data_size, 1);
} else {
/* There are other xattrs packed in the same item. */
ret = btrfs_delete_one_dir_name(trans, root, path, di);
if (ret)
goto out;
- btrfs_extend_item(fs_info, path, data_size);
+ btrfs_extend_item(trans, path, data_size);
}
- item = btrfs_item_nr(slot);
ptr = btrfs_item_ptr(leaf, slot, char);
- ptr += btrfs_item_size(leaf, item) - data_size;
+ ptr += btrfs_item_size(leaf, slot) - data_size;
di = (struct btrfs_dir_item *)ptr;
btrfs_set_dir_data_len(leaf, di, size);
data_ptr = ((unsigned long)(di + 1)) + name_len;
write_extent_buffer(leaf, value, data_ptr, size);
- btrfs_mark_buffer_dirty(leaf);
} else {
/*
* Insert, and we had space for the xattr, so path->slots[0] is
@@ -213,50 +200,73 @@ static int do_setxattr(struct btrfs_trans_handle *trans,
*/
}
out:
- btrfs_free_path(path);
+ if (!ret) {
+ set_bit(BTRFS_INODE_COPY_EVERYTHING,
+ &BTRFS_I(inode)->runtime_flags);
+ clear_bit(BTRFS_INODE_NO_XATTRS, &BTRFS_I(inode)->runtime_flags);
+ }
return ret;
}
/*
* @value: "" makes the attribute to empty, NULL removes it
*/
-int btrfs_setxattr(struct btrfs_trans_handle *trans,
- struct inode *inode, const char *name,
- const void *value, size_t size, int flags)
+int btrfs_setxattr_trans(struct inode *inode, const char *name,
+ const void *value, size_t size, int flags)
{
struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_trans_handle *trans;
+ const bool start_trans = (current->journal_info == NULL);
int ret;
- if (btrfs_root_readonly(root))
- return -EROFS;
-
- if (trans)
- return do_setxattr(trans, inode, name, value, size, flags);
-
- trans = btrfs_start_transaction(root, 2);
- if (IS_ERR(trans))
- return PTR_ERR(trans);
+ if (start_trans) {
+ /*
+ * 1 unit for inserting/updating/deleting the xattr
+ * 1 unit for the inode item update
+ */
+ trans = btrfs_start_transaction(root, 2);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+ } else {
+ /*
+ * This can happen when smack is enabled and a directory is being
+ * created. It happens through d_instantiate_new(), which calls
+ * smack_d_instantiate(), which in turn calls __vfs_setxattr() to
+ * set the transmute xattr (XATTR_NAME_SMACKTRANSMUTE) on the
+ * inode. We have already reserved space for the xattr and inode
+ * update at btrfs_mkdir(), so just use the transaction handle.
+ * We don't join or start a transaction, as that will reset the
+ * block_rsv of the handle and trigger a warning for the start
+ * case.
+ */
+ ASSERT(strncmp(name, XATTR_SECURITY_PREFIX,
+ XATTR_SECURITY_PREFIX_LEN) == 0);
+ trans = current->journal_info;
+ }
- ret = do_setxattr(trans, inode, name, value, size, flags);
+ ret = btrfs_setxattr(trans, inode, name, value, size, flags);
if (ret)
goto out;
inode_inc_iversion(inode);
- inode->i_ctime = current_time(inode);
- set_bit(BTRFS_INODE_COPY_EVERYTHING, &BTRFS_I(inode)->runtime_flags);
- ret = btrfs_update_inode(trans, root, inode);
- BUG_ON(ret);
+ inode_set_ctime_current(inode);
+ ret = btrfs_update_inode(trans, BTRFS_I(inode));
+ if (ret)
+ btrfs_abort_transaction(trans, ret);
out:
- btrfs_end_transaction(trans);
+ if (start_trans)
+ btrfs_end_transaction(trans);
return ret;
}
ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
{
+ struct btrfs_key found_key;
struct btrfs_key key;
struct inode *inode = d_inode(dentry);
struct btrfs_root *root = BTRFS_I(inode)->root;
- struct btrfs_path *path;
+ BTRFS_PATH_AUTO_FREE(path);
+ int iter_ret = 0;
int ret = 0;
size_t total_size = 0, size_left = size;
@@ -275,47 +285,26 @@ ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
path->reada = READA_FORWARD;
/* search for our xattrs */
- ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
- if (ret < 0)
- goto err;
-
- while (1) {
+ btrfs_for_each_slot(root, &key, &found_key, path, iter_ret) {
struct extent_buffer *leaf;
int slot;
struct btrfs_dir_item *di;
- struct btrfs_key found_key;
u32 item_size;
u32 cur;
leaf = path->nodes[0];
slot = path->slots[0];
- /* this is where we start walking through the path */
- if (slot >= btrfs_header_nritems(leaf)) {
- /*
- * if we've reached the last slot in this leaf we need
- * to go to the next leaf and reset everything
- */
- ret = btrfs_next_leaf(root, path);
- if (ret < 0)
- goto err;
- else if (ret > 0)
- break;
- continue;
- }
-
- btrfs_item_key_to_cpu(leaf, &found_key, slot);
-
/* check to make sure this item is what we want */
if (found_key.objectid != key.objectid)
break;
if (found_key.type > BTRFS_XATTR_ITEM_KEY)
break;
if (found_key.type < BTRFS_XATTR_ITEM_KEY)
- goto next_item;
+ continue;
di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
- item_size = btrfs_item_size_nr(leaf, slot);
+ item_size = btrfs_item_size(leaf, slot);
cur = 0;
while (cur < item_size) {
u16 name_len = btrfs_dir_name_len(leaf, di);
@@ -332,8 +321,8 @@ ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
goto next;
if (!buffer || (name_len + 1) > size_left) {
- ret = -ERANGE;
- goto err;
+ iter_ret = -ERANGE;
+ break;
}
read_extent_buffer(leaf, buffer, name_ptr, name_len);
@@ -345,13 +334,12 @@ next:
cur += this_len;
di = (struct btrfs_dir_item *)((char *)di + this_len);
}
-next_item:
- path->slots[0]++;
}
- ret = total_size;
-err:
- btrfs_free_path(path);
+ if (iter_ret < 0)
+ ret = iter_ret;
+ else
+ ret = total_size;
return ret;
}
@@ -365,27 +353,105 @@ static int btrfs_xattr_handler_get(const struct xattr_handler *handler,
}
static int btrfs_xattr_handler_set(const struct xattr_handler *handler,
+ struct mnt_idmap *idmap,
struct dentry *unused, struct inode *inode,
const char *name, const void *buffer,
size_t size, int flags)
{
+ if (btrfs_root_readonly(BTRFS_I(inode)->root))
+ return -EROFS;
+
name = xattr_full_name(handler, name);
- return btrfs_setxattr(NULL, inode, name, buffer, size, flags);
+ return btrfs_setxattr_trans(inode, name, buffer, size, flags);
+}
+
+static int btrfs_xattr_handler_get_security(const struct xattr_handler *handler,
+ struct dentry *unused,
+ struct inode *inode,
+ const char *name, void *buffer,
+ size_t size)
+{
+ int ret;
+ bool is_cap = false;
+
+ name = xattr_full_name(handler, name);
+
+ /*
+ * security.capability doesn't cache the results, so calls into us
+ * constantly to see if there's a capability xattr. Cache the result
+ * here in order to avoid wasting time doing lookups for xattrs we know
+ * don't exist.
+ */
+ if (strcmp(name, XATTR_NAME_CAPS) == 0) {
+ is_cap = true;
+ if (test_bit(BTRFS_INODE_NO_CAP_XATTR, &BTRFS_I(inode)->runtime_flags))
+ return -ENODATA;
+ }
+
+ ret = btrfs_getxattr(inode, name, buffer, size);
+ if (ret == -ENODATA && is_cap)
+ set_bit(BTRFS_INODE_NO_CAP_XATTR, &BTRFS_I(inode)->runtime_flags);
+ return ret;
+}
+
+static int btrfs_xattr_handler_set_security(const struct xattr_handler *handler,
+ struct mnt_idmap *idmap,
+ struct dentry *unused,
+ struct inode *inode,
+ const char *name,
+ const void *buffer,
+ size_t size, int flags)
+{
+ if (btrfs_root_readonly(BTRFS_I(inode)->root))
+ return -EROFS;
+
+ name = xattr_full_name(handler, name);
+ if (strcmp(name, XATTR_NAME_CAPS) == 0)
+ clear_bit(BTRFS_INODE_NO_CAP_XATTR, &BTRFS_I(inode)->runtime_flags);
+
+ return btrfs_setxattr_trans(inode, name, buffer, size, flags);
}
static int btrfs_xattr_handler_set_prop(const struct xattr_handler *handler,
+ struct mnt_idmap *idmap,
struct dentry *unused, struct inode *inode,
const char *name, const void *value,
size_t size, int flags)
{
+ int ret;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+
name = xattr_full_name(handler, name);
- return btrfs_set_prop(inode, name, value, size, flags);
+ ret = btrfs_validate_prop(BTRFS_I(inode), name, value, size);
+ if (ret)
+ return ret;
+
+ if (btrfs_ignore_prop(BTRFS_I(inode), name))
+ return 0;
+
+ trans = btrfs_start_transaction(root, 2);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+
+ ret = btrfs_set_prop(trans, BTRFS_I(inode), name, value, size, flags);
+ if (!ret) {
+ inode_inc_iversion(inode);
+ inode_set_ctime_current(inode);
+ ret = btrfs_update_inode(trans, BTRFS_I(inode));
+ if (ret)
+ btrfs_abort_transaction(trans, ret);
+ }
+
+ btrfs_end_transaction(trans);
+
+ return ret;
}
static const struct xattr_handler btrfs_security_xattr_handler = {
.prefix = XATTR_SECURITY_PREFIX,
- .get = btrfs_xattr_handler_get,
- .set = btrfs_xattr_handler_set,
+ .get = btrfs_xattr_handler_get_security,
+ .set = btrfs_xattr_handler_set_security,
};
static const struct xattr_handler btrfs_trusted_xattr_handler = {
@@ -406,12 +472,8 @@ static const struct xattr_handler btrfs_btrfs_xattr_handler = {
.set = btrfs_xattr_handler_set_prop,
};
-const struct xattr_handler *btrfs_xattr_handlers[] = {
+const struct xattr_handler * const btrfs_xattr_handlers[] = {
&btrfs_security_xattr_handler,
-#ifdef CONFIG_BTRFS_FS_POSIX_ACL
- &posix_acl_access_xattr_handler,
- &posix_acl_default_xattr_handler,
-#endif
&btrfs_trusted_xattr_handler,
&btrfs_user_xattr_handler,
&btrfs_btrfs_xattr_handler,
@@ -419,13 +481,13 @@ const struct xattr_handler *btrfs_xattr_handlers[] = {
};
static int btrfs_initxattrs(struct inode *inode,
- const struct xattr *xattr_array, void *fs_info)
+ const struct xattr *xattr_array, void *fs_private)
{
+ struct btrfs_trans_handle *trans = fs_private;
const struct xattr *xattr;
- struct btrfs_trans_handle *trans = fs_info;
unsigned int nofs_flag;
char *name;
- int err = 0;
+ int ret = 0;
/*
* We're holding a transaction handle, so use a NOFS memory allocation
@@ -433,22 +495,27 @@ static int btrfs_initxattrs(struct inode *inode,
*/
nofs_flag = memalloc_nofs_save();
for (xattr = xattr_array; xattr->name != NULL; xattr++) {
- name = kmalloc(XATTR_SECURITY_PREFIX_LEN +
- strlen(xattr->name) + 1, GFP_KERNEL);
+ const size_t name_len = XATTR_SECURITY_PREFIX_LEN +
+ strlen(xattr->name) + 1;
+
+ name = kmalloc(name_len, GFP_KERNEL);
if (!name) {
- err = -ENOMEM;
+ ret = -ENOMEM;
break;
}
- strcpy(name, XATTR_SECURITY_PREFIX);
- strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name);
- err = btrfs_setxattr(trans, inode, name, xattr->value,
- xattr->value_len, 0);
+ scnprintf(name, name_len, "%s%s", XATTR_SECURITY_PREFIX, xattr->name);
+
+ if (strcmp(name, XATTR_NAME_CAPS) == 0)
+ clear_bit(BTRFS_INODE_NO_CAP_XATTR, &BTRFS_I(inode)->runtime_flags);
+
+ ret = btrfs_setxattr(trans, inode, name, xattr->value,
+ xattr->value_len, 0);
kfree(name);
- if (err < 0)
+ if (ret < 0)
break;
}
memalloc_nofs_restore(nofs_flag);
- return err;
+ return ret;
}
int btrfs_xattr_security_init(struct btrfs_trans_handle *trans,
generated by cgit (git 2.34.1) at 2025-12-24 19:58:59 +0000