linux-stable/fs/ceph/xattr.c
Yan, Zheng 315f240880 ceph: fix security xattr deadlock
When security is enabled, security module can call filesystem's
getxattr/setxattr callbacks during d_instantiate(). For cephfs,
d_instantiate() is usually called by MDS' dispatch thread, while
handling MDS reply. If the MDS reply does not include xattrs and
corresponding caps, getxattr/setxattr need to send a new request
to MDS and waits for the reply. This makes MDS' dispatch sleep,
nobody handles later MDS replies.

The fix is make sure lookup/atomic_open reply include xattrs and
corresponding caps. So getxattr can be handled by cached xattrs.
This requires some modification to both MDS and request message.
(Client tells MDS what caps it wants; MDS encodes proper caps in
the reply)

Smack security module may call setxattr during d_instantiate().
Unlike getxattr, we can't force MDS to issue CEPH_CAP_XATTR_EXCL
to us. So just make setxattr return error when called by MDS'
dispatch thread.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2016-03-25 18:51:55 +01:00

1230 lines
31 KiB
C

#include <linux/ceph/ceph_debug.h>
#include <linux/ceph/pagelist.h>
#include "super.h"
#include "mds_client.h"
#include <linux/ceph/decode.h>
#include <linux/xattr.h>
#include <linux/posix_acl_xattr.h>
#include <linux/slab.h>
#define XATTR_CEPH_PREFIX "ceph."
#define XATTR_CEPH_PREFIX_LEN (sizeof (XATTR_CEPH_PREFIX) - 1)
static int __remove_xattr(struct ceph_inode_info *ci,
struct ceph_inode_xattr *xattr);
/*
* List of handlers for synthetic system.* attributes. Other
* attributes are handled directly.
*/
const struct xattr_handler *ceph_xattr_handlers[] = {
#ifdef CONFIG_CEPH_FS_POSIX_ACL
&posix_acl_access_xattr_handler,
&posix_acl_default_xattr_handler,
#endif
NULL,
};
static bool ceph_is_valid_xattr(const char *name)
{
return !strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN) ||
!strncmp(name, XATTR_SECURITY_PREFIX,
XATTR_SECURITY_PREFIX_LEN) ||
!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) ||
!strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) ||
!strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
}
/*
* These define virtual xattrs exposing the recursive directory
* statistics and layout metadata.
*/
struct ceph_vxattr {
char *name;
size_t name_size; /* strlen(name) + 1 (for '\0') */
size_t (*getxattr_cb)(struct ceph_inode_info *ci, char *val,
size_t size);
bool readonly, hidden;
bool (*exists_cb)(struct ceph_inode_info *ci);
};
/* layouts */
static bool ceph_vxattrcb_layout_exists(struct ceph_inode_info *ci)
{
size_t s;
char *p = (char *)&ci->i_layout;
for (s = 0; s < sizeof(ci->i_layout); s++, p++)
if (*p)
return true;
return false;
}
static size_t ceph_vxattrcb_layout(struct ceph_inode_info *ci, char *val,
size_t size)
{
int ret;
struct ceph_fs_client *fsc = ceph_sb_to_client(ci->vfs_inode.i_sb);
struct ceph_osd_client *osdc = &fsc->client->osdc;
s64 pool = ceph_file_layout_pg_pool(ci->i_layout);
const char *pool_name;
char buf[128];
dout("ceph_vxattrcb_layout %p\n", &ci->vfs_inode);
down_read(&osdc->map_sem);
pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, pool);
if (pool_name) {
size_t len = strlen(pool_name);
ret = snprintf(buf, sizeof(buf),
"stripe_unit=%lld stripe_count=%lld object_size=%lld pool=",
(unsigned long long)ceph_file_layout_su(ci->i_layout),
(unsigned long long)ceph_file_layout_stripe_count(ci->i_layout),
(unsigned long long)ceph_file_layout_object_size(ci->i_layout));
if (!size) {
ret += len;
} else if (ret + len > size) {
ret = -ERANGE;
} else {
memcpy(val, buf, ret);
memcpy(val + ret, pool_name, len);
ret += len;
}
} else {
ret = snprintf(buf, sizeof(buf),
"stripe_unit=%lld stripe_count=%lld object_size=%lld pool=%lld",
(unsigned long long)ceph_file_layout_su(ci->i_layout),
(unsigned long long)ceph_file_layout_stripe_count(ci->i_layout),
(unsigned long long)ceph_file_layout_object_size(ci->i_layout),
(unsigned long long)pool);
if (size) {
if (ret <= size)
memcpy(val, buf, ret);
else
ret = -ERANGE;
}
}
up_read(&osdc->map_sem);
return ret;
}
static size_t ceph_vxattrcb_layout_stripe_unit(struct ceph_inode_info *ci,
char *val, size_t size)
{
return snprintf(val, size, "%lld",
(unsigned long long)ceph_file_layout_su(ci->i_layout));
}
static size_t ceph_vxattrcb_layout_stripe_count(struct ceph_inode_info *ci,
char *val, size_t size)
{
return snprintf(val, size, "%lld",
(unsigned long long)ceph_file_layout_stripe_count(ci->i_layout));
}
static size_t ceph_vxattrcb_layout_object_size(struct ceph_inode_info *ci,
char *val, size_t size)
{
return snprintf(val, size, "%lld",
(unsigned long long)ceph_file_layout_object_size(ci->i_layout));
}
static size_t ceph_vxattrcb_layout_pool(struct ceph_inode_info *ci,
char *val, size_t size)
{
int ret;
struct ceph_fs_client *fsc = ceph_sb_to_client(ci->vfs_inode.i_sb);
struct ceph_osd_client *osdc = &fsc->client->osdc;
s64 pool = ceph_file_layout_pg_pool(ci->i_layout);
const char *pool_name;
down_read(&osdc->map_sem);
pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, pool);
if (pool_name)
ret = snprintf(val, size, "%s", pool_name);
else
ret = snprintf(val, size, "%lld", (unsigned long long)pool);
up_read(&osdc->map_sem);
return ret;
}
/* directories */
static size_t ceph_vxattrcb_dir_entries(struct ceph_inode_info *ci, char *val,
size_t size)
{
return snprintf(val, size, "%lld", ci->i_files + ci->i_subdirs);
}
static size_t ceph_vxattrcb_dir_files(struct ceph_inode_info *ci, char *val,
size_t size)
{
return snprintf(val, size, "%lld", ci->i_files);
}
static size_t ceph_vxattrcb_dir_subdirs(struct ceph_inode_info *ci, char *val,
size_t size)
{
return snprintf(val, size, "%lld", ci->i_subdirs);
}
static size_t ceph_vxattrcb_dir_rentries(struct ceph_inode_info *ci, char *val,
size_t size)
{
return snprintf(val, size, "%lld", ci->i_rfiles + ci->i_rsubdirs);
}
static size_t ceph_vxattrcb_dir_rfiles(struct ceph_inode_info *ci, char *val,
size_t size)
{
return snprintf(val, size, "%lld", ci->i_rfiles);
}
static size_t ceph_vxattrcb_dir_rsubdirs(struct ceph_inode_info *ci, char *val,
size_t size)
{
return snprintf(val, size, "%lld", ci->i_rsubdirs);
}
static size_t ceph_vxattrcb_dir_rbytes(struct ceph_inode_info *ci, char *val,
size_t size)
{
return snprintf(val, size, "%lld", ci->i_rbytes);
}
static size_t ceph_vxattrcb_dir_rctime(struct ceph_inode_info *ci, char *val,
size_t size)
{
return snprintf(val, size, "%ld.09%ld", (long)ci->i_rctime.tv_sec,
(long)ci->i_rctime.tv_nsec);
}
#define CEPH_XATTR_NAME(_type, _name) XATTR_CEPH_PREFIX #_type "." #_name
#define CEPH_XATTR_NAME2(_type, _name, _name2) \
XATTR_CEPH_PREFIX #_type "." #_name "." #_name2
#define XATTR_NAME_CEPH(_type, _name) \
{ \
.name = CEPH_XATTR_NAME(_type, _name), \
.name_size = sizeof (CEPH_XATTR_NAME(_type, _name)), \
.getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name, \
.readonly = true, \
.hidden = false, \
.exists_cb = NULL, \
}
#define XATTR_LAYOUT_FIELD(_type, _name, _field) \
{ \
.name = CEPH_XATTR_NAME2(_type, _name, _field), \
.name_size = sizeof (CEPH_XATTR_NAME2(_type, _name, _field)), \
.getxattr_cb = ceph_vxattrcb_ ## _name ## _ ## _field, \
.readonly = false, \
.hidden = true, \
.exists_cb = ceph_vxattrcb_layout_exists, \
}
static struct ceph_vxattr ceph_dir_vxattrs[] = {
{
.name = "ceph.dir.layout",
.name_size = sizeof("ceph.dir.layout"),
.getxattr_cb = ceph_vxattrcb_layout,
.readonly = false,
.hidden = true,
.exists_cb = ceph_vxattrcb_layout_exists,
},
XATTR_LAYOUT_FIELD(dir, layout, stripe_unit),
XATTR_LAYOUT_FIELD(dir, layout, stripe_count),
XATTR_LAYOUT_FIELD(dir, layout, object_size),
XATTR_LAYOUT_FIELD(dir, layout, pool),
XATTR_NAME_CEPH(dir, entries),
XATTR_NAME_CEPH(dir, files),
XATTR_NAME_CEPH(dir, subdirs),
XATTR_NAME_CEPH(dir, rentries),
XATTR_NAME_CEPH(dir, rfiles),
XATTR_NAME_CEPH(dir, rsubdirs),
XATTR_NAME_CEPH(dir, rbytes),
XATTR_NAME_CEPH(dir, rctime),
{ .name = NULL, 0 } /* Required table terminator */
};
static size_t ceph_dir_vxattrs_name_size; /* total size of all names */
/* files */
static struct ceph_vxattr ceph_file_vxattrs[] = {
{
.name = "ceph.file.layout",
.name_size = sizeof("ceph.file.layout"),
.getxattr_cb = ceph_vxattrcb_layout,
.readonly = false,
.hidden = true,
.exists_cb = ceph_vxattrcb_layout_exists,
},
XATTR_LAYOUT_FIELD(file, layout, stripe_unit),
XATTR_LAYOUT_FIELD(file, layout, stripe_count),
XATTR_LAYOUT_FIELD(file, layout, object_size),
XATTR_LAYOUT_FIELD(file, layout, pool),
{ .name = NULL, 0 } /* Required table terminator */
};
static size_t ceph_file_vxattrs_name_size; /* total size of all names */
static struct ceph_vxattr *ceph_inode_vxattrs(struct inode *inode)
{
if (S_ISDIR(inode->i_mode))
return ceph_dir_vxattrs;
else if (S_ISREG(inode->i_mode))
return ceph_file_vxattrs;
return NULL;
}
static size_t ceph_vxattrs_name_size(struct ceph_vxattr *vxattrs)
{
if (vxattrs == ceph_dir_vxattrs)
return ceph_dir_vxattrs_name_size;
if (vxattrs == ceph_file_vxattrs)
return ceph_file_vxattrs_name_size;
BUG_ON(vxattrs);
return 0;
}
/*
* Compute the aggregate size (including terminating '\0') of all
* virtual extended attribute names in the given vxattr table.
*/
static size_t __init vxattrs_name_size(struct ceph_vxattr *vxattrs)
{
struct ceph_vxattr *vxattr;
size_t size = 0;
for (vxattr = vxattrs; vxattr->name; vxattr++)
if (!vxattr->hidden)
size += vxattr->name_size;
return size;
}
/* Routines called at initialization and exit time */
void __init ceph_xattr_init(void)
{
ceph_dir_vxattrs_name_size = vxattrs_name_size(ceph_dir_vxattrs);
ceph_file_vxattrs_name_size = vxattrs_name_size(ceph_file_vxattrs);
}
void ceph_xattr_exit(void)
{
ceph_dir_vxattrs_name_size = 0;
ceph_file_vxattrs_name_size = 0;
}
static struct ceph_vxattr *ceph_match_vxattr(struct inode *inode,
const char *name)
{
struct ceph_vxattr *vxattr = ceph_inode_vxattrs(inode);
if (vxattr) {
while (vxattr->name) {
if (!strcmp(vxattr->name, name))
return vxattr;
vxattr++;
}
}
return NULL;
}
static int __set_xattr(struct ceph_inode_info *ci,
const char *name, int name_len,
const char *val, int val_len,
int flags, int update_xattr,
struct ceph_inode_xattr **newxattr)
{
struct rb_node **p;
struct rb_node *parent = NULL;
struct ceph_inode_xattr *xattr = NULL;
int c;
int new = 0;
p = &ci->i_xattrs.index.rb_node;
while (*p) {
parent = *p;
xattr = rb_entry(parent, struct ceph_inode_xattr, node);
c = strncmp(name, xattr->name, min(name_len, xattr->name_len));
if (c < 0)
p = &(*p)->rb_left;
else if (c > 0)
p = &(*p)->rb_right;
else {
if (name_len == xattr->name_len)
break;
else if (name_len < xattr->name_len)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
}
xattr = NULL;
}
if (update_xattr) {
int err = 0;
if (xattr && (flags & XATTR_CREATE))
err = -EEXIST;
else if (!xattr && (flags & XATTR_REPLACE))
err = -ENODATA;
if (err) {
kfree(name);
kfree(val);
return err;
}
if (update_xattr < 0) {
if (xattr)
__remove_xattr(ci, xattr);
kfree(name);
return 0;
}
}
if (!xattr) {
new = 1;
xattr = *newxattr;
xattr->name = name;
xattr->name_len = name_len;
xattr->should_free_name = update_xattr;
ci->i_xattrs.count++;
dout("__set_xattr count=%d\n", ci->i_xattrs.count);
} else {
kfree(*newxattr);
*newxattr = NULL;
if (xattr->should_free_val)
kfree((void *)xattr->val);
if (update_xattr) {
kfree((void *)name);
name = xattr->name;
}
ci->i_xattrs.names_size -= xattr->name_len;
ci->i_xattrs.vals_size -= xattr->val_len;
}
ci->i_xattrs.names_size += name_len;
ci->i_xattrs.vals_size += val_len;
if (val)
xattr->val = val;
else
xattr->val = "";
xattr->val_len = val_len;
xattr->dirty = update_xattr;
xattr->should_free_val = (val && update_xattr);
if (new) {
rb_link_node(&xattr->node, parent, p);
rb_insert_color(&xattr->node, &ci->i_xattrs.index);
dout("__set_xattr_val p=%p\n", p);
}
dout("__set_xattr_val added %llx.%llx xattr %p %s=%.*s\n",
ceph_vinop(&ci->vfs_inode), xattr, name, val_len, val);
return 0;
}
static struct ceph_inode_xattr *__get_xattr(struct ceph_inode_info *ci,
const char *name)
{
struct rb_node **p;
struct rb_node *parent = NULL;
struct ceph_inode_xattr *xattr = NULL;
int name_len = strlen(name);
int c;
p = &ci->i_xattrs.index.rb_node;
while (*p) {
parent = *p;
xattr = rb_entry(parent, struct ceph_inode_xattr, node);
c = strncmp(name, xattr->name, xattr->name_len);
if (c == 0 && name_len > xattr->name_len)
c = 1;
if (c < 0)
p = &(*p)->rb_left;
else if (c > 0)
p = &(*p)->rb_right;
else {
dout("__get_xattr %s: found %.*s\n", name,
xattr->val_len, xattr->val);
return xattr;
}
}
dout("__get_xattr %s: not found\n", name);
return NULL;
}
static void __free_xattr(struct ceph_inode_xattr *xattr)
{
BUG_ON(!xattr);
if (xattr->should_free_name)
kfree((void *)xattr->name);
if (xattr->should_free_val)
kfree((void *)xattr->val);
kfree(xattr);
}
static int __remove_xattr(struct ceph_inode_info *ci,
struct ceph_inode_xattr *xattr)
{
if (!xattr)
return -ENODATA;
rb_erase(&xattr->node, &ci->i_xattrs.index);
if (xattr->should_free_name)
kfree((void *)xattr->name);
if (xattr->should_free_val)
kfree((void *)xattr->val);
ci->i_xattrs.names_size -= xattr->name_len;
ci->i_xattrs.vals_size -= xattr->val_len;
ci->i_xattrs.count--;
kfree(xattr);
return 0;
}
static int __remove_xattr_by_name(struct ceph_inode_info *ci,
const char *name)
{
struct rb_node **p;
struct ceph_inode_xattr *xattr;
int err;
p = &ci->i_xattrs.index.rb_node;
xattr = __get_xattr(ci, name);
err = __remove_xattr(ci, xattr);
return err;
}
static char *__copy_xattr_names(struct ceph_inode_info *ci,
char *dest)
{
struct rb_node *p;
struct ceph_inode_xattr *xattr = NULL;
p = rb_first(&ci->i_xattrs.index);
dout("__copy_xattr_names count=%d\n", ci->i_xattrs.count);
while (p) {
xattr = rb_entry(p, struct ceph_inode_xattr, node);
memcpy(dest, xattr->name, xattr->name_len);
dest[xattr->name_len] = '\0';
dout("dest=%s %p (%s) (%d/%d)\n", dest, xattr, xattr->name,
xattr->name_len, ci->i_xattrs.names_size);
dest += xattr->name_len + 1;
p = rb_next(p);
}
return dest;
}
void __ceph_destroy_xattrs(struct ceph_inode_info *ci)
{
struct rb_node *p, *tmp;
struct ceph_inode_xattr *xattr = NULL;
p = rb_first(&ci->i_xattrs.index);
dout("__ceph_destroy_xattrs p=%p\n", p);
while (p) {
xattr = rb_entry(p, struct ceph_inode_xattr, node);
tmp = p;
p = rb_next(tmp);
dout("__ceph_destroy_xattrs next p=%p (%.*s)\n", p,
xattr->name_len, xattr->name);
rb_erase(tmp, &ci->i_xattrs.index);
__free_xattr(xattr);
}
ci->i_xattrs.names_size = 0;
ci->i_xattrs.vals_size = 0;
ci->i_xattrs.index_version = 0;
ci->i_xattrs.count = 0;
ci->i_xattrs.index = RB_ROOT;
}
static int __build_xattrs(struct inode *inode)
__releases(ci->i_ceph_lock)
__acquires(ci->i_ceph_lock)
{
u32 namelen;
u32 numattr = 0;
void *p, *end;
u32 len;
const char *name, *val;
struct ceph_inode_info *ci = ceph_inode(inode);
int xattr_version;
struct ceph_inode_xattr **xattrs = NULL;
int err = 0;
int i;
dout("__build_xattrs() len=%d\n",
ci->i_xattrs.blob ? (int)ci->i_xattrs.blob->vec.iov_len : 0);
if (ci->i_xattrs.index_version >= ci->i_xattrs.version)
return 0; /* already built */
__ceph_destroy_xattrs(ci);
start:
/* updated internal xattr rb tree */
if (ci->i_xattrs.blob && ci->i_xattrs.blob->vec.iov_len > 4) {
p = ci->i_xattrs.blob->vec.iov_base;
end = p + ci->i_xattrs.blob->vec.iov_len;
ceph_decode_32_safe(&p, end, numattr, bad);
xattr_version = ci->i_xattrs.version;
spin_unlock(&ci->i_ceph_lock);
xattrs = kcalloc(numattr, sizeof(struct ceph_inode_xattr *),
GFP_NOFS);
err = -ENOMEM;
if (!xattrs)
goto bad_lock;
for (i = 0; i < numattr; i++) {
xattrs[i] = kmalloc(sizeof(struct ceph_inode_xattr),
GFP_NOFS);
if (!xattrs[i])
goto bad_lock;
}
spin_lock(&ci->i_ceph_lock);
if (ci->i_xattrs.version != xattr_version) {
/* lost a race, retry */
for (i = 0; i < numattr; i++)
kfree(xattrs[i]);
kfree(xattrs);
xattrs = NULL;
goto start;
}
err = -EIO;
while (numattr--) {
ceph_decode_32_safe(&p, end, len, bad);
namelen = len;
name = p;
p += len;
ceph_decode_32_safe(&p, end, len, bad);
val = p;
p += len;
err = __set_xattr(ci, name, namelen, val, len,
0, 0, &xattrs[numattr]);
if (err < 0)
goto bad;
}
kfree(xattrs);
}
ci->i_xattrs.index_version = ci->i_xattrs.version;
ci->i_xattrs.dirty = false;
return err;
bad_lock:
spin_lock(&ci->i_ceph_lock);
bad:
if (xattrs) {
for (i = 0; i < numattr; i++)
kfree(xattrs[i]);
kfree(xattrs);
}
ci->i_xattrs.names_size = 0;
return err;
}
static int __get_required_blob_size(struct ceph_inode_info *ci, int name_size,
int val_size)
{
/*
* 4 bytes for the length, and additional 4 bytes per each xattr name,
* 4 bytes per each value
*/
int size = 4 + ci->i_xattrs.count*(4 + 4) +
ci->i_xattrs.names_size +
ci->i_xattrs.vals_size;
dout("__get_required_blob_size c=%d names.size=%d vals.size=%d\n",
ci->i_xattrs.count, ci->i_xattrs.names_size,
ci->i_xattrs.vals_size);
if (name_size)
size += 4 + 4 + name_size + val_size;
return size;
}
/*
* If there are dirty xattrs, reencode xattrs into the prealloc_blob
* and swap into place.
*/
void __ceph_build_xattrs_blob(struct ceph_inode_info *ci)
{
struct rb_node *p;
struct ceph_inode_xattr *xattr = NULL;
void *dest;
dout("__build_xattrs_blob %p\n", &ci->vfs_inode);
if (ci->i_xattrs.dirty) {
int need = __get_required_blob_size(ci, 0, 0);
BUG_ON(need > ci->i_xattrs.prealloc_blob->alloc_len);
p = rb_first(&ci->i_xattrs.index);
dest = ci->i_xattrs.prealloc_blob->vec.iov_base;
ceph_encode_32(&dest, ci->i_xattrs.count);
while (p) {
xattr = rb_entry(p, struct ceph_inode_xattr, node);
ceph_encode_32(&dest, xattr->name_len);
memcpy(dest, xattr->name, xattr->name_len);
dest += xattr->name_len;
ceph_encode_32(&dest, xattr->val_len);
memcpy(dest, xattr->val, xattr->val_len);
dest += xattr->val_len;
p = rb_next(p);
}
/* adjust buffer len; it may be larger than we need */
ci->i_xattrs.prealloc_blob->vec.iov_len =
dest - ci->i_xattrs.prealloc_blob->vec.iov_base;
if (ci->i_xattrs.blob)
ceph_buffer_put(ci->i_xattrs.blob);
ci->i_xattrs.blob = ci->i_xattrs.prealloc_blob;
ci->i_xattrs.prealloc_blob = NULL;
ci->i_xattrs.dirty = false;
ci->i_xattrs.version++;
}
}
static inline int __get_request_mask(struct inode *in) {
struct ceph_mds_request *req = current->journal_info;
int mask = 0;
if (req && req->r_target_inode == in) {
if (req->r_op == CEPH_MDS_OP_LOOKUP ||
req->r_op == CEPH_MDS_OP_LOOKUPINO ||
req->r_op == CEPH_MDS_OP_LOOKUPPARENT ||
req->r_op == CEPH_MDS_OP_GETATTR) {
mask = le32_to_cpu(req->r_args.getattr.mask);
} else if (req->r_op == CEPH_MDS_OP_OPEN ||
req->r_op == CEPH_MDS_OP_CREATE) {
mask = le32_to_cpu(req->r_args.open.mask);
}
}
return mask;
}
ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
size_t size)
{
struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_inode_xattr *xattr;
struct ceph_vxattr *vxattr = NULL;
int req_mask;
int err;
if (!ceph_is_valid_xattr(name))
return -ENODATA;
/* let's see if a virtual xattr was requested */
vxattr = ceph_match_vxattr(inode, name);
if (vxattr) {
err = -ENODATA;
if (!(vxattr->exists_cb && !vxattr->exists_cb(ci)))
err = vxattr->getxattr_cb(ci, value, size);
return err;
}
req_mask = __get_request_mask(inode);
spin_lock(&ci->i_ceph_lock);
dout("getxattr %p ver=%lld index_ver=%lld\n", inode,
ci->i_xattrs.version, ci->i_xattrs.index_version);
if (ci->i_xattrs.version == 0 ||
!((req_mask & CEPH_CAP_XATTR_SHARED) ||
__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1))) {
spin_unlock(&ci->i_ceph_lock);
/* security module gets xattr while filling trace */
if (current->journal_info != NULL) {
pr_warn_ratelimited("sync getxattr %p "
"during filling trace\n", inode);
return -EBUSY;
}
/* get xattrs from mds (if we don't already have them) */
err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
if (err)
return err;
spin_lock(&ci->i_ceph_lock);
}
err = __build_xattrs(inode);
if (err < 0)
goto out;
err = -ENODATA; /* == ENOATTR */
xattr = __get_xattr(ci, name);
if (!xattr)
goto out;
err = -ERANGE;
if (size && size < xattr->val_len)
goto out;
err = xattr->val_len;
if (size == 0)
goto out;
memcpy(value, xattr->val, xattr->val_len);
if (current->journal_info != NULL &&
!strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN))
ci->i_ceph_flags |= CEPH_I_SEC_INITED;
out:
spin_unlock(&ci->i_ceph_lock);
return err;
}
ssize_t ceph_getxattr(struct dentry *dentry, const char *name, void *value,
size_t size)
{
if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
return generic_getxattr(dentry, name, value, size);
return __ceph_getxattr(d_inode(dentry), name, value, size);
}
ssize_t ceph_listxattr(struct dentry *dentry, char *names, size_t size)
{
struct inode *inode = d_inode(dentry);
struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_vxattr *vxattrs = ceph_inode_vxattrs(inode);
u32 vir_namelen = 0;
u32 namelen;
int err;
u32 len;
int i;
spin_lock(&ci->i_ceph_lock);
dout("listxattr %p ver=%lld index_ver=%lld\n", inode,
ci->i_xattrs.version, ci->i_xattrs.index_version);
if (ci->i_xattrs.version == 0 ||
!__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1)) {
spin_unlock(&ci->i_ceph_lock);
err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
if (err)
return err;
spin_lock(&ci->i_ceph_lock);
}
err = __build_xattrs(inode);
if (err < 0)
goto out;
/*
* Start with virtual dir xattr names (if any) (including
* terminating '\0' characters for each).
*/
vir_namelen = ceph_vxattrs_name_size(vxattrs);
/* adding 1 byte per each variable due to the null termination */
namelen = ci->i_xattrs.names_size + ci->i_xattrs.count;
err = -ERANGE;
if (size && vir_namelen + namelen > size)
goto out;
err = namelen + vir_namelen;
if (size == 0)
goto out;
names = __copy_xattr_names(ci, names);
/* virtual xattr names, too */
err = namelen;
if (vxattrs) {
for (i = 0; vxattrs[i].name; i++) {
if (!vxattrs[i].hidden &&
!(vxattrs[i].exists_cb &&
!vxattrs[i].exists_cb(ci))) {
len = sprintf(names, "%s", vxattrs[i].name);
names += len + 1;
err += len + 1;
}
}
}
out:
spin_unlock(&ci->i_ceph_lock);
return err;
}
static int ceph_sync_setxattr(struct dentry *dentry, const char *name,
const char *value, size_t size, int flags)
{
struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
struct inode *inode = d_inode(dentry);
struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_mds_request *req;
struct ceph_mds_client *mdsc = fsc->mdsc;
struct ceph_pagelist *pagelist = NULL;
int err;
if (size > 0) {
/* copy value into pagelist */
pagelist = kmalloc(sizeof(*pagelist), GFP_NOFS);
if (!pagelist)
return -ENOMEM;
ceph_pagelist_init(pagelist);
err = ceph_pagelist_append(pagelist, value, size);
if (err)
goto out;
} else if (!value) {
flags |= CEPH_XATTR_REMOVE;
}
dout("setxattr value=%.*s\n", (int)size, value);
/* do request */
req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETXATTR,
USE_AUTH_MDS);
if (IS_ERR(req)) {
err = PTR_ERR(req);
goto out;
}
req->r_args.setxattr.flags = cpu_to_le32(flags);
req->r_path2 = kstrdup(name, GFP_NOFS);
if (!req->r_path2) {
ceph_mdsc_put_request(req);
err = -ENOMEM;
goto out;
}
req->r_pagelist = pagelist;
pagelist = NULL;
req->r_inode = inode;
ihold(inode);
req->r_num_caps = 1;
req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
dout("xattr.ver (before): %lld\n", ci->i_xattrs.version);
err = ceph_mdsc_do_request(mdsc, NULL, req);
ceph_mdsc_put_request(req);
dout("xattr.ver (after): %lld\n", ci->i_xattrs.version);
out:
if (pagelist)
ceph_pagelist_release(pagelist);
return err;
}
int __ceph_setxattr(struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
struct inode *inode = d_inode(dentry);
struct ceph_vxattr *vxattr;
struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_mds_client *mdsc = ceph_sb_to_client(dentry->d_sb)->mdsc;
struct ceph_cap_flush *prealloc_cf = NULL;
int issued;
int err;
int dirty = 0;
int name_len = strlen(name);
int val_len = size;
char *newname = NULL;
char *newval = NULL;
struct ceph_inode_xattr *xattr = NULL;
int required_blob_size;
bool lock_snap_rwsem = false;
if (!ceph_is_valid_xattr(name))
return -EOPNOTSUPP;
vxattr = ceph_match_vxattr(inode, name);
if (vxattr && vxattr->readonly)
return -EOPNOTSUPP;
/* pass any unhandled ceph.* xattrs through to the MDS */
if (!strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN))
goto do_sync_unlocked;
/* preallocate memory for xattr name, value, index node */
err = -ENOMEM;
newname = kmemdup(name, name_len + 1, GFP_NOFS);
if (!newname)
goto out;
if (val_len) {
newval = kmemdup(value, val_len, GFP_NOFS);
if (!newval)
goto out;
}
xattr = kmalloc(sizeof(struct ceph_inode_xattr), GFP_NOFS);
if (!xattr)
goto out;
prealloc_cf = ceph_alloc_cap_flush();
if (!prealloc_cf)
goto out;
spin_lock(&ci->i_ceph_lock);
retry:
issued = __ceph_caps_issued(ci, NULL);
if (ci->i_xattrs.version == 0 || !(issued & CEPH_CAP_XATTR_EXCL))
goto do_sync;
if (!lock_snap_rwsem && !ci->i_head_snapc) {
lock_snap_rwsem = true;
if (!down_read_trylock(&mdsc->snap_rwsem)) {
spin_unlock(&ci->i_ceph_lock);
down_read(&mdsc->snap_rwsem);
spin_lock(&ci->i_ceph_lock);
goto retry;
}
}
dout("setxattr %p issued %s\n", inode, ceph_cap_string(issued));
__build_xattrs(inode);
required_blob_size = __get_required_blob_size(ci, name_len, val_len);
if (!ci->i_xattrs.prealloc_blob ||
required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
struct ceph_buffer *blob;
spin_unlock(&ci->i_ceph_lock);
dout(" preaallocating new blob size=%d\n", required_blob_size);
blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
if (!blob)
goto do_sync_unlocked;
spin_lock(&ci->i_ceph_lock);
if (ci->i_xattrs.prealloc_blob)
ceph_buffer_put(ci->i_xattrs.prealloc_blob);
ci->i_xattrs.prealloc_blob = blob;
goto retry;
}
err = __set_xattr(ci, newname, name_len, newval, val_len,
flags, value ? 1 : -1, &xattr);
if (!err) {
dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL,
&prealloc_cf);
ci->i_xattrs.dirty = true;
inode->i_ctime = current_fs_time(inode->i_sb);
}
spin_unlock(&ci->i_ceph_lock);
if (lock_snap_rwsem)
up_read(&mdsc->snap_rwsem);
if (dirty)
__mark_inode_dirty(inode, dirty);
ceph_free_cap_flush(prealloc_cf);
return err;
do_sync:
spin_unlock(&ci->i_ceph_lock);
do_sync_unlocked:
if (lock_snap_rwsem)
up_read(&mdsc->snap_rwsem);
/* security module set xattr while filling trace */
if (current->journal_info != NULL) {
pr_warn_ratelimited("sync setxattr %p "
"during filling trace\n", inode);
err = -EBUSY;
} else {
err = ceph_sync_setxattr(dentry, name, value, size, flags);
}
out:
ceph_free_cap_flush(prealloc_cf);
kfree(newname);
kfree(newval);
kfree(xattr);
return err;
}
int ceph_setxattr(struct dentry *dentry, const char *name,
const void *value, size_t size, int flags)
{
if (ceph_snap(d_inode(dentry)) != CEPH_NOSNAP)
return -EROFS;
if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
return generic_setxattr(dentry, name, value, size, flags);
if (size == 0)
value = ""; /* empty EA, do not remove */
return __ceph_setxattr(dentry, name, value, size, flags);
}
static int ceph_send_removexattr(struct dentry *dentry, const char *name)
{
struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
struct ceph_mds_client *mdsc = fsc->mdsc;
struct inode *inode = d_inode(dentry);
struct ceph_mds_request *req;
int err;
req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_RMXATTR,
USE_AUTH_MDS);
if (IS_ERR(req))
return PTR_ERR(req);
req->r_path2 = kstrdup(name, GFP_NOFS);
if (!req->r_path2)
return -ENOMEM;
req->r_inode = inode;
ihold(inode);
req->r_num_caps = 1;
req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
err = ceph_mdsc_do_request(mdsc, NULL, req);
ceph_mdsc_put_request(req);
return err;
}
int __ceph_removexattr(struct dentry *dentry, const char *name)
{
struct inode *inode = d_inode(dentry);
struct ceph_vxattr *vxattr;
struct ceph_inode_info *ci = ceph_inode(inode);
struct ceph_mds_client *mdsc = ceph_sb_to_client(dentry->d_sb)->mdsc;
struct ceph_cap_flush *prealloc_cf = NULL;
int issued;
int err;
int required_blob_size;
int dirty;
bool lock_snap_rwsem = false;
if (!ceph_is_valid_xattr(name))
return -EOPNOTSUPP;
vxattr = ceph_match_vxattr(inode, name);
if (vxattr && vxattr->readonly)
return -EOPNOTSUPP;
/* pass any unhandled ceph.* xattrs through to the MDS */
if (!strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN))
goto do_sync_unlocked;
prealloc_cf = ceph_alloc_cap_flush();
if (!prealloc_cf)
return -ENOMEM;
err = -ENOMEM;
spin_lock(&ci->i_ceph_lock);
retry:
issued = __ceph_caps_issued(ci, NULL);
if (ci->i_xattrs.version == 0 || !(issued & CEPH_CAP_XATTR_EXCL))
goto do_sync;
if (!lock_snap_rwsem && !ci->i_head_snapc) {
lock_snap_rwsem = true;
if (!down_read_trylock(&mdsc->snap_rwsem)) {
spin_unlock(&ci->i_ceph_lock);
down_read(&mdsc->snap_rwsem);
spin_lock(&ci->i_ceph_lock);
goto retry;
}
}
dout("removexattr %p issued %s\n", inode, ceph_cap_string(issued));
__build_xattrs(inode);
required_blob_size = __get_required_blob_size(ci, 0, 0);
if (!ci->i_xattrs.prealloc_blob ||
required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
struct ceph_buffer *blob;
spin_unlock(&ci->i_ceph_lock);
dout(" preaallocating new blob size=%d\n", required_blob_size);
blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
if (!blob)
goto do_sync_unlocked;
spin_lock(&ci->i_ceph_lock);
if (ci->i_xattrs.prealloc_blob)
ceph_buffer_put(ci->i_xattrs.prealloc_blob);
ci->i_xattrs.prealloc_blob = blob;
goto retry;
}
err = __remove_xattr_by_name(ceph_inode(inode), name);
dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL,
&prealloc_cf);
ci->i_xattrs.dirty = true;
inode->i_ctime = current_fs_time(inode->i_sb);
spin_unlock(&ci->i_ceph_lock);
if (lock_snap_rwsem)
up_read(&mdsc->snap_rwsem);
if (dirty)
__mark_inode_dirty(inode, dirty);
ceph_free_cap_flush(prealloc_cf);
return err;
do_sync:
spin_unlock(&ci->i_ceph_lock);
do_sync_unlocked:
if (lock_snap_rwsem)
up_read(&mdsc->snap_rwsem);
ceph_free_cap_flush(prealloc_cf);
err = ceph_send_removexattr(dentry, name);
return err;
}
int ceph_removexattr(struct dentry *dentry, const char *name)
{
if (ceph_snap(d_inode(dentry)) != CEPH_NOSNAP)
return -EROFS;
if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
return generic_removexattr(dentry, name);
return __ceph_removexattr(dentry, name);
}
#ifdef CONFIG_SECURITY
bool ceph_security_xattr_wanted(struct inode *in)
{
return in->i_security != NULL;
}
bool ceph_security_xattr_deadlock(struct inode *in)
{
struct ceph_inode_info *ci;
bool ret;
if (in->i_security == NULL)
return false;
ci = ceph_inode(in);
spin_lock(&ci->i_ceph_lock);
ret = !(ci->i_ceph_flags & CEPH_I_SEC_INITED) &&
!(ci->i_xattrs.version > 0 &&
__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 0));
spin_unlock(&ci->i_ceph_lock);
return ret;
}
#endif