linux-stable/fs/orangefs/namei.c
Martin Brandenburg c62da5853d orangefs: Avoid symlink upcall if target is too long.
Previously the client-core detected this condition by sheer luck!

Since we used strncpy, no NUL byte would be included on the name. The
client-core would call strlen, which would read past the end of its
buffer, but return a number large enough that the client-core would
return ENAMETOOLONG.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
2016-03-09 13:26:39 -05:00

462 lines
12 KiB
C

/*
* (C) 2001 Clemson University and The University of Chicago
*
* See COPYING in top-level directory.
*/
/*
* Linux VFS namei operations.
*/
#include "protocol.h"
#include "orangefs-kernel.h"
/*
* Get a newly allocated inode to go with a negative dentry.
*/
static int orangefs_create(struct inode *dir,
struct dentry *dentry,
umode_t mode,
bool exclusive)
{
struct orangefs_inode_s *parent = ORANGEFS_I(dir);
struct orangefs_kernel_op_s *new_op;
struct inode *inode;
int ret;
gossip_debug(GOSSIP_NAME_DEBUG, "%s: %s\n",
__func__,
dentry->d_name.name);
new_op = op_alloc(ORANGEFS_VFS_OP_CREATE);
if (!new_op)
return -ENOMEM;
new_op->upcall.req.create.parent_refn = parent->refn;
fill_default_sys_attrs(new_op->upcall.req.create.attributes,
ORANGEFS_TYPE_METAFILE, mode);
strncpy(new_op->upcall.req.create.d_name,
dentry->d_name.name, ORANGEFS_NAME_MAX);
ret = service_operation(new_op, __func__, get_interruptible_flag(dir));
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: %s: handle:%pU: fsid:%d: new_op:%p: ret:%d:\n",
__func__,
dentry->d_name.name,
&new_op->downcall.resp.create.refn.khandle,
new_op->downcall.resp.create.refn.fs_id,
new_op,
ret);
if (ret < 0)
goto out;
inode = orangefs_new_inode(dir->i_sb, dir, S_IFREG | mode, 0,
&new_op->downcall.resp.create.refn);
if (IS_ERR(inode)) {
gossip_err("%s: Failed to allocate inode for file :%s:\n",
__func__,
dentry->d_name.name);
ret = PTR_ERR(inode);
goto out;
}
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: Assigned inode :%pU: for file :%s:\n",
__func__,
get_khandle_from_ino(inode),
dentry->d_name.name);
d_instantiate(dentry, inode);
unlock_new_inode(inode);
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: dentry instantiated for %s\n",
__func__,
dentry->d_name.name);
SetMtimeFlag(parent);
dir->i_mtime = dir->i_ctime = current_fs_time(dir->i_sb);
mark_inode_dirty_sync(dir);
ret = 0;
out:
op_release(new_op);
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: %s: returning %d\n",
__func__,
dentry->d_name.name,
ret);
return ret;
}
/*
* Attempt to resolve an object name (dentry->d_name), parent handle, and
* fsid into a handle for the object.
*/
static struct dentry *orangefs_lookup(struct inode *dir, struct dentry *dentry,
unsigned int flags)
{
struct orangefs_inode_s *parent = ORANGEFS_I(dir);
struct orangefs_kernel_op_s *new_op;
struct inode *inode;
struct dentry *res;
int ret = -EINVAL;
/*
* in theory we could skip a lookup here (if the intent is to
* create) in order to avoid a potentially failed lookup, but
* leaving it in can skip a valid lookup and try to create a file
* that already exists (e.g. the vfs already handles checking for
* -EEXIST on O_EXCL opens, which is broken if we skip this lookup
* in the create path)
*/
gossip_debug(GOSSIP_NAME_DEBUG, "%s called on %s\n",
__func__, dentry->d_name.name);
if (dentry->d_name.len > (ORANGEFS_NAME_MAX - 1))
return ERR_PTR(-ENAMETOOLONG);
new_op = op_alloc(ORANGEFS_VFS_OP_LOOKUP);
if (!new_op)
return ERR_PTR(-ENOMEM);
new_op->upcall.req.lookup.sym_follow = ORANGEFS_LOOKUP_LINK_NO_FOLLOW;
gossip_debug(GOSSIP_NAME_DEBUG, "%s:%s:%d using parent %pU\n",
__FILE__,
__func__,
__LINE__,
&parent->refn.khandle);
new_op->upcall.req.lookup.parent_refn = parent->refn;
strncpy(new_op->upcall.req.lookup.d_name, dentry->d_name.name,
ORANGEFS_NAME_MAX);
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: doing lookup on %s under %pU,%d\n",
__func__,
new_op->upcall.req.lookup.d_name,
&new_op->upcall.req.lookup.parent_refn.khandle,
new_op->upcall.req.lookup.parent_refn.fs_id);
ret = service_operation(new_op, __func__, get_interruptible_flag(dir));
gossip_debug(GOSSIP_NAME_DEBUG,
"Lookup Got %pU, fsid %d (ret=%d)\n",
&new_op->downcall.resp.lookup.refn.khandle,
new_op->downcall.resp.lookup.refn.fs_id,
ret);
if (ret < 0) {
if (ret == -ENOENT) {
/*
* if no inode was found, add a negative dentry to
* dcache anyway; if we don't, we don't hold expected
* lookup semantics and we most noticeably break
* during directory renames.
*
* however, if the operation failed or exited, do not
* add the dentry (e.g. in the case that a touch is
* issued on a file that already exists that was
* interrupted during this lookup -- no need to add
* another negative dentry for an existing file)
*/
gossip_debug(GOSSIP_NAME_DEBUG,
"orangefs_lookup: Adding *negative* dentry "
"%p for %s\n",
dentry,
dentry->d_name.name);
d_add(dentry, NULL);
res = NULL;
goto out;
}
/* must be a non-recoverable error */
res = ERR_PTR(ret);
goto out;
}
inode = orangefs_iget(dir->i_sb, &new_op->downcall.resp.lookup.refn);
if (IS_ERR(inode)) {
gossip_debug(GOSSIP_NAME_DEBUG,
"error %ld from iget\n", PTR_ERR(inode));
res = ERR_CAST(inode);
goto out;
}
gossip_debug(GOSSIP_NAME_DEBUG,
"%s:%s:%d "
"Found good inode [%lu] with count [%d]\n",
__FILE__,
__func__,
__LINE__,
inode->i_ino,
(int)atomic_read(&inode->i_count));
/* update dentry/inode pair into dcache */
res = d_splice_alias(inode, dentry);
gossip_debug(GOSSIP_NAME_DEBUG,
"Lookup success (inode ct = %d)\n",
(int)atomic_read(&inode->i_count));
out:
op_release(new_op);
return res;
}
/* return 0 on success; non-zero otherwise */
static int orangefs_unlink(struct inode *dir, struct dentry *dentry)
{
struct inode *inode = dentry->d_inode;
struct orangefs_inode_s *parent = ORANGEFS_I(dir);
struct orangefs_kernel_op_s *new_op;
int ret;
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: called on %s\n"
" (inode %pU): Parent is %pU | fs_id %d\n",
__func__,
dentry->d_name.name,
get_khandle_from_ino(inode),
&parent->refn.khandle,
parent->refn.fs_id);
new_op = op_alloc(ORANGEFS_VFS_OP_REMOVE);
if (!new_op)
return -ENOMEM;
new_op->upcall.req.remove.parent_refn = parent->refn;
strncpy(new_op->upcall.req.remove.d_name, dentry->d_name.name,
ORANGEFS_NAME_MAX);
ret = service_operation(new_op, "orangefs_unlink",
get_interruptible_flag(inode));
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: service_operation returned:%d:\n",
__func__,
ret);
op_release(new_op);
if (!ret) {
drop_nlink(inode);
SetMtimeFlag(parent);
dir->i_mtime = dir->i_ctime = current_fs_time(dir->i_sb);
mark_inode_dirty_sync(dir);
}
return ret;
}
static int orangefs_symlink(struct inode *dir,
struct dentry *dentry,
const char *symname)
{
struct orangefs_inode_s *parent = ORANGEFS_I(dir);
struct orangefs_kernel_op_s *new_op;
struct inode *inode;
int mode = 755;
int ret;
gossip_debug(GOSSIP_NAME_DEBUG, "%s: called\n", __func__);
if (!symname)
return -EINVAL;
if (strlen(symname)+1 > ORANGEFS_NAME_MAX)
return -ENAMETOOLONG;
new_op = op_alloc(ORANGEFS_VFS_OP_SYMLINK);
if (!new_op)
return -ENOMEM;
new_op->upcall.req.sym.parent_refn = parent->refn;
fill_default_sys_attrs(new_op->upcall.req.sym.attributes,
ORANGEFS_TYPE_SYMLINK,
mode);
strncpy(new_op->upcall.req.sym.entry_name,
dentry->d_name.name,
ORANGEFS_NAME_MAX);
strncpy(new_op->upcall.req.sym.target, symname, ORANGEFS_NAME_MAX);
ret = service_operation(new_op, __func__, get_interruptible_flag(dir));
gossip_debug(GOSSIP_NAME_DEBUG,
"Symlink Got ORANGEFS handle %pU on fsid %d (ret=%d)\n",
&new_op->downcall.resp.sym.refn.khandle,
new_op->downcall.resp.sym.refn.fs_id, ret);
if (ret < 0) {
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: failed with error code %d\n",
__func__, ret);
goto out;
}
inode = orangefs_new_inode(dir->i_sb, dir, S_IFLNK | mode, 0,
&new_op->downcall.resp.sym.refn);
if (IS_ERR(inode)) {
gossip_err
("*** Failed to allocate orangefs symlink inode\n");
ret = PTR_ERR(inode);
goto out;
}
gossip_debug(GOSSIP_NAME_DEBUG,
"Assigned symlink inode new number of %pU\n",
get_khandle_from_ino(inode));
d_instantiate(dentry, inode);
unlock_new_inode(inode);
gossip_debug(GOSSIP_NAME_DEBUG,
"Inode (Symlink) %pU -> %s\n",
get_khandle_from_ino(inode),
dentry->d_name.name);
SetMtimeFlag(parent);
dir->i_mtime = dir->i_ctime = current_fs_time(dir->i_sb);
mark_inode_dirty_sync(dir);
ret = 0;
out:
op_release(new_op);
return ret;
}
static int orangefs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
struct orangefs_inode_s *parent = ORANGEFS_I(dir);
struct orangefs_kernel_op_s *new_op;
struct inode *inode;
int ret;
new_op = op_alloc(ORANGEFS_VFS_OP_MKDIR);
if (!new_op)
return -ENOMEM;
new_op->upcall.req.mkdir.parent_refn = parent->refn;
fill_default_sys_attrs(new_op->upcall.req.mkdir.attributes,
ORANGEFS_TYPE_DIRECTORY, mode);
strncpy(new_op->upcall.req.mkdir.d_name,
dentry->d_name.name, ORANGEFS_NAME_MAX);
ret = service_operation(new_op, __func__, get_interruptible_flag(dir));
gossip_debug(GOSSIP_NAME_DEBUG,
"Mkdir Got ORANGEFS handle %pU on fsid %d\n",
&new_op->downcall.resp.mkdir.refn.khandle,
new_op->downcall.resp.mkdir.refn.fs_id);
if (ret < 0) {
gossip_debug(GOSSIP_NAME_DEBUG,
"%s: failed with error code %d\n",
__func__, ret);
goto out;
}
inode = orangefs_new_inode(dir->i_sb, dir, S_IFDIR | mode, 0,
&new_op->downcall.resp.mkdir.refn);
if (IS_ERR(inode)) {
gossip_err("*** Failed to allocate orangefs dir inode\n");
ret = PTR_ERR(inode);
goto out;
}
gossip_debug(GOSSIP_NAME_DEBUG,
"Assigned dir inode new number of %pU\n",
get_khandle_from_ino(inode));
d_instantiate(dentry, inode);
unlock_new_inode(inode);
gossip_debug(GOSSIP_NAME_DEBUG,
"Inode (Directory) %pU -> %s\n",
get_khandle_from_ino(inode),
dentry->d_name.name);
/*
* NOTE: we have no good way to keep nlink consistent for directories
* across clients; keep constant at 1.
*/
SetMtimeFlag(parent);
dir->i_mtime = dir->i_ctime = current_fs_time(dir->i_sb);
mark_inode_dirty_sync(dir);
out:
op_release(new_op);
return ret;
}
static int orangefs_rename(struct inode *old_dir,
struct dentry *old_dentry,
struct inode *new_dir,
struct dentry *new_dentry)
{
struct orangefs_kernel_op_s *new_op;
int ret;
gossip_debug(GOSSIP_NAME_DEBUG,
"orangefs_rename: called (%s/%s => %s/%s) ct=%d\n",
old_dentry->d_parent->d_name.name,
old_dentry->d_name.name,
new_dentry->d_parent->d_name.name,
new_dentry->d_name.name,
d_count(new_dentry));
new_op = op_alloc(ORANGEFS_VFS_OP_RENAME);
if (!new_op)
return -EINVAL;
new_op->upcall.req.rename.old_parent_refn = ORANGEFS_I(old_dir)->refn;
new_op->upcall.req.rename.new_parent_refn = ORANGEFS_I(new_dir)->refn;
strncpy(new_op->upcall.req.rename.d_old_name,
old_dentry->d_name.name,
ORANGEFS_NAME_MAX);
strncpy(new_op->upcall.req.rename.d_new_name,
new_dentry->d_name.name,
ORANGEFS_NAME_MAX);
ret = service_operation(new_op,
"orangefs_rename",
get_interruptible_flag(old_dentry->d_inode));
gossip_debug(GOSSIP_NAME_DEBUG,
"orangefs_rename: got downcall status %d\n",
ret);
if (new_dentry->d_inode)
new_dentry->d_inode->i_ctime = CURRENT_TIME;
op_release(new_op);
return ret;
}
/* ORANGEFS implementation of VFS inode operations for directories */
struct inode_operations orangefs_dir_inode_operations = {
.lookup = orangefs_lookup,
.get_acl = orangefs_get_acl,
.set_acl = orangefs_set_acl,
.create = orangefs_create,
.unlink = orangefs_unlink,
.symlink = orangefs_symlink,
.mkdir = orangefs_mkdir,
.rmdir = orangefs_unlink,
.rename = orangefs_rename,
.setattr = orangefs_setattr,
.getattr = orangefs_getattr,
.setxattr = generic_setxattr,
.getxattr = generic_getxattr,
.removexattr = generic_removexattr,
.listxattr = orangefs_listxattr,
.permission = orangefs_permission,
};