mirror of
https://github.com/tbsdtv/linux_media.git
synced 2025-07-23 12:43:29 +02:00
fuse: move ioctl to separate source file
Next patch will expand ioctl code and fuse/file.c is large enough as it is. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This commit is contained in:
Miklos Szeredi
@@ -7,7 +7,7 @@ obj-$(CONFIG_FUSE_FS) += fuse.o
|
|||||||
obj-$(CONFIG_CUSE) += cuse.o
|
obj-$(CONFIG_CUSE) += cuse.o
|
||||||
obj-$(CONFIG_VIRTIO_FS) += virtiofs.o
|
obj-$(CONFIG_VIRTIO_FS) += virtiofs.o
|
||||||
|
|
||||||
fuse-y := dev.o dir.o file.o inode.o control.o xattr.o acl.o readdir.o
|
fuse-y := dev.o dir.o file.o inode.o control.o xattr.o acl.o readdir.o ioctl.o
|
||||||
fuse-$(CONFIG_FUSE_DAX) += dax.o
|
fuse-$(CONFIG_FUSE_DAX) += dax.o
|
||||||
|
|
||||||
virtiofs-y := virtio_fs.o
|
virtiofs-y := virtio_fs.o
|
||||||
|
|||||||
380
fs/fuse/file.c
380
fs/fuse/file.c
@@ -14,24 +14,11 @@
|
|||||||
#include <linux/sched.h>
|
#include <linux/sched.h>
|
||||||
#include <linux/sched/signal.h>
|
#include <linux/sched/signal.h>
|
||||||
#include <linux/module.h>
|
#include <linux/module.h>
|
||||||
#include <linux/compat.h>
|
|
||||||
#include <linux/swap.h>
|
#include <linux/swap.h>
|
||||||
#include <linux/falloc.h>
|
#include <linux/falloc.h>
|
||||||
#include <linux/uio.h>
|
#include <linux/uio.h>
|
||||||
#include <linux/fs.h>
|
#include <linux/fs.h>
|
||||||
|
|
||||||
static struct page **fuse_pages_alloc(unsigned int npages, gfp_t flags,
|
|
||||||
struct fuse_page_desc **desc)
|
|
||||||
{
|
|
||||||
struct page **pages;
|
|
||||||
|
|
||||||
pages = kzalloc(npages * (sizeof(struct page *) +
|
|
||||||
sizeof(struct fuse_page_desc)), flags);
|
|
||||||
*desc = (void *) (pages + npages);
|
|
||||||
|
|
||||||
return pages;
|
|
||||||
}
|
|
||||||
|
|
||||||
static int fuse_send_open(struct fuse_mount *fm, u64 nodeid, struct file *file,
|
static int fuse_send_open(struct fuse_mount *fm, u64 nodeid, struct file *file,
|
||||||
int opcode, struct fuse_open_out *outargp)
|
int opcode, struct fuse_open_out *outargp)
|
||||||
{
|
{
|
||||||
@@ -1346,16 +1333,6 @@ out:
|
|||||||
return written ? written : err;
|
return written ? written : err;
|
||||||
}
|
}
|
||||||
|
|
||||||
static inline void fuse_page_descs_length_init(struct fuse_page_desc *descs,
|
|
||||||
unsigned int index,
|
|
||||||
unsigned int nr_pages)
|
|
||||||
{
|
|
||||||
int i;
|
|
||||||
|
|
||||||
for (i = index; i < index + nr_pages; i++)
|
|
||||||
descs[i].length = PAGE_SIZE - descs[i].offset;
|
|
||||||
}
|
|
||||||
|
|
||||||
static inline unsigned long fuse_get_user_addr(const struct iov_iter *ii)
|
static inline unsigned long fuse_get_user_addr(const struct iov_iter *ii)
|
||||||
{
|
{
|
||||||
return (unsigned long)ii->iov->iov_base + ii->iov_offset;
|
return (unsigned long)ii->iov->iov_base + ii->iov_offset;
|
||||||
@@ -2636,363 +2613,6 @@ static loff_t fuse_file_llseek(struct file *file, loff_t offset, int whence)
|
|||||||
return retval;
|
return retval;
|
||||||
}
|
}
|
||||||
|
|
||||||
/*
|
|
||||||
* CUSE servers compiled on 32bit broke on 64bit kernels because the
|
|
||||||
* ABI was defined to be 'struct iovec' which is different on 32bit
|
|
||||||
* and 64bit. Fortunately we can determine which structure the server
|
|
||||||
* used from the size of the reply.
|
|
||||||
*/
|
|
||||||
static int fuse_copy_ioctl_iovec_old(struct iovec *dst, void *src,
|
|
||||||
size_t transferred, unsigned count,
|
|
||||||
bool is_compat)
|
|
||||||
{
|
|
||||||
#ifdef CONFIG_COMPAT
|
|
||||||
if (count * sizeof(struct compat_iovec) == transferred) {
|
|
||||||
struct compat_iovec *ciov = src;
|
|
||||||
unsigned i;
|
|
||||||
|
|
||||||
/*
|
|
||||||
* With this interface a 32bit server cannot support
|
|
||||||
* non-compat (i.e. ones coming from 64bit apps) ioctl
|
|
||||||
* requests
|
|
||||||
*/
|
|
||||||
if (!is_compat)
|
|
||||||
return -EINVAL;
|
|
||||||
|
|
||||||
for (i = 0; i < count; i++) {
|
|
||||||
dst[i].iov_base = compat_ptr(ciov[i].iov_base);
|
|
||||||
dst[i].iov_len = ciov[i].iov_len;
|
|
||||||
}
|
|
||||||
return 0;
|
|
||||||
}
|
|
||||||
#endif
|
|
||||||
|
|
||||||
if (count * sizeof(struct iovec) != transferred)
|
|
||||||
return -EIO;
|
|
||||||
|
|
||||||
memcpy(dst, src, transferred);
|
|
||||||
return 0;
|
|
||||||
}
|
|
||||||
|
|
||||||
/* Make sure iov_length() won't overflow */
|
|
||||||
static int fuse_verify_ioctl_iov(struct fuse_conn *fc, struct iovec *iov,
|
|
||||||
size_t count)
|
|
||||||
{
|
|
||||||
size_t n;
|
|
||||||
u32 max = fc->max_pages << PAGE_SHIFT;
|
|
||||||
|
|
||||||
for (n = 0; n < count; n++, iov++) {
|
|
||||||
if (iov->iov_len > (size_t) max)
|
|
||||||
return -ENOMEM;
|
|
||||||
max -= iov->iov_len;
|
|
||||||
}
|
|
||||||
return 0;
|
|
||||||
}
|
|
||||||
|
|
||||||
static int fuse_copy_ioctl_iovec(struct fuse_conn *fc, struct iovec *dst,
|
|
||||||
void *src, size_t transferred, unsigned count,
|
|
||||||
bool is_compat)
|
|
||||||
{
|
|
||||||
unsigned i;
|
|
||||||
struct fuse_ioctl_iovec *fiov = src;
|
|
||||||
|
|
||||||
if (fc->minor < 16) {
|
|
||||||
return fuse_copy_ioctl_iovec_old(dst, src, transferred,
|
|
||||||
count, is_compat);
|
|
||||||
}
|
|
||||||
|
|
||||||
if (count * sizeof(struct fuse_ioctl_iovec) != transferred)
|
|
||||||
return -EIO;
|
|
||||||
|
|
||||||
for (i = 0; i < count; i++) {
|
|
||||||
/* Did the server supply an inappropriate value? */
|
|
||||||
if (fiov[i].base != (unsigned long) fiov[i].base ||
|
|
||||||
fiov[i].len != (unsigned long) fiov[i].len)
|
|
||||||
return -EIO;
|
|
||||||
|
|
||||||
dst[i].iov_base = (void __user *) (unsigned long) fiov[i].base;
|
|
||||||
dst[i].iov_len = (size_t) fiov[i].len;
|
|
||||||
|
|
||||||
#ifdef CONFIG_COMPAT
|
|
||||||
if (is_compat &&
|
|
||||||
(ptr_to_compat(dst[i].iov_base) != fiov[i].base ||
|
|
||||||
(compat_size_t) dst[i].iov_len != fiov[i].len))
|
|
||||||
return -EIO;
|
|
||||||
#endif
|
|
||||||
}
|
|
||||||
|
|
||||||
return 0;
|
|
||||||
}
|
|
||||||
|
|
||||||
|
|
||||||
/*
|
|
||||||
* For ioctls, there is no generic way to determine how much memory
|
|
||||||
* needs to be read and/or written. Furthermore, ioctls are allowed
|
|
||||||
* to dereference the passed pointer, so the parameter requires deep
|
|
||||||
* copying but FUSE has no idea whatsoever about what to copy in or
|
|
||||||
* out.
|
|
||||||
*
|
|
||||||
* This is solved by allowing FUSE server to retry ioctl with
|
|
||||||
* necessary in/out iovecs. Let's assume the ioctl implementation
|
|
||||||
* needs to read in the following structure.
|
|
||||||
*
|
|
||||||
* struct a {
|
|
||||||
* char *buf;
|
|
||||||
* size_t buflen;
|
|
||||||
* }
|
|
||||||
*
|
|
||||||
* On the first callout to FUSE server, inarg->in_size and
|
|
||||||
* inarg->out_size will be NULL; then, the server completes the ioctl
|
|
||||||
* with FUSE_IOCTL_RETRY set in out->flags, out->in_iovs set to 1 and
|
|
||||||
* the actual iov array to
|
|
||||||
*
|
|
||||||
* { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) } }
|
|
||||||
*
|
|
||||||
* which tells FUSE to copy in the requested area and retry the ioctl.
|
|
||||||
* On the second round, the server has access to the structure and
|
|
||||||
* from that it can tell what to look for next, so on the invocation,
|
|
||||||
* it sets FUSE_IOCTL_RETRY, out->in_iovs to 2 and iov array to
|
|
||||||
*
|
|
||||||
* { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) },
|
|
||||||
* { .iov_base = a.buf, .iov_len = a.buflen } }
|
|
||||||
*
|
|
||||||
* FUSE will copy both struct a and the pointed buffer from the
|
|
||||||
* process doing the ioctl and retry ioctl with both struct a and the
|
|
||||||
* buffer.
|
|
||||||
*
|
|
||||||
* This time, FUSE server has everything it needs and completes ioctl
|
|
||||||
* without FUSE_IOCTL_RETRY which finishes the ioctl call.
|
|
||||||
*
|
|
||||||
* Copying data out works the same way.
|
|
||||||
*
|
|
||||||
* Note that if FUSE_IOCTL_UNRESTRICTED is clear, the kernel
|
|
||||||
* automatically initializes in and out iovs by decoding @cmd with
|
|
||||||
* _IOC_* macros and the server is not allowed to request RETRY. This
|
|
||||||
* limits ioctl data transfers to well-formed ioctls and is the forced
|
|
||||||
* behavior for all FUSE servers.
|
|
||||||
*/
|
|
||||||
long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
|
|
||||||
unsigned int flags)
|
|
||||||
{
|
|
||||||
struct fuse_file *ff = file->private_data;
|
|
||||||
struct fuse_mount *fm = ff->fm;
|
|
||||||
struct fuse_ioctl_in inarg = {
|
|
||||||
.fh = ff->fh,
|
|
||||||
.cmd = cmd,
|
|
||||||
.arg = arg,
|
|
||||||
.flags = flags
|
|
||||||
};
|
|
||||||
struct fuse_ioctl_out outarg;
|
|
||||||
struct iovec *iov_page = NULL;
|
|
||||||
struct iovec *in_iov = NULL, *out_iov = NULL;
|
|
||||||
unsigned int in_iovs = 0, out_iovs = 0, max_pages;
|
|
||||||
size_t in_size, out_size, c;
|
|
||||||
ssize_t transferred;
|
|
||||||
int err, i;
|
|
||||||
struct iov_iter ii;
|
|
||||||
struct fuse_args_pages ap = {};
|
|
||||||
|
|
||||||
#if BITS_PER_LONG == 32
|
|
||||||
inarg.flags |= FUSE_IOCTL_32BIT;
|
|
||||||
#else
|
|
||||||
if (flags & FUSE_IOCTL_COMPAT) {
|
|
||||||
inarg.flags |= FUSE_IOCTL_32BIT;
|
|
||||||
#ifdef CONFIG_X86_X32
|
|
||||||
if (in_x32_syscall())
|
|
||||||
inarg.flags |= FUSE_IOCTL_COMPAT_X32;
|
|
||||||
#endif
|
|
||||||
}
|
|
||||||
#endif
|
|
||||||
|
|
||||||
/* assume all the iovs returned by client always fits in a page */
|
|
||||||
BUILD_BUG_ON(sizeof(struct fuse_ioctl_iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE);
|
|
||||||
|
|
||||||
err = -ENOMEM;
|
|
||||||
ap.pages = fuse_pages_alloc(fm->fc->max_pages, GFP_KERNEL, &ap.descs);
|
|
||||||
iov_page = (struct iovec *) __get_free_page(GFP_KERNEL);
|
|
||||||
if (!ap.pages || !iov_page)
|
|
||||||
goto out;
|
|
||||||
|
|
||||||
fuse_page_descs_length_init(ap.descs, 0, fm->fc->max_pages);
|
|
||||||
|
|
||||||
/*
|
|
||||||
* If restricted, initialize IO parameters as encoded in @cmd.
|
|
||||||
* RETRY from server is not allowed.
|
|
||||||
*/
|
|
||||||
if (!(flags & FUSE_IOCTL_UNRESTRICTED)) {
|
|
||||||
struct iovec *iov = iov_page;
|
|
||||||
|
|
||||||
iov->iov_base = (void __user *)arg;
|
|
||||||
|
|
||||||
switch (cmd) {
|
|
||||||
case FS_IOC_GETFLAGS:
|
|
||||||
case FS_IOC_SETFLAGS:
|
|
||||||
iov->iov_len = sizeof(int);
|
|
||||||
break;
|
|
||||||
default:
|
|
||||||
iov->iov_len = _IOC_SIZE(cmd);
|
|
||||||
break;
|
|
||||||
}
|
|
||||||
|
|
||||||
if (_IOC_DIR(cmd) & _IOC_WRITE) {
|
|
||||||
in_iov = iov;
|
|
||||||
in_iovs = 1;
|
|
||||||
}
|
|
||||||
|
|
||||||
if (_IOC_DIR(cmd) & _IOC_READ) {
|
|
||||||
out_iov = iov;
|
|
||||||
out_iovs = 1;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
retry:
|
|
||||||
inarg.in_size = in_size = iov_length(in_iov, in_iovs);
|
|
||||||
inarg.out_size = out_size = iov_length(out_iov, out_iovs);
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Out data can be used either for actual out data or iovs,
|
|
||||||
* make sure there always is at least one page.
|
|
||||||
*/
|
|
||||||
out_size = max_t(size_t, out_size, PAGE_SIZE);
|
|
||||||
max_pages = DIV_ROUND_UP(max(in_size, out_size), PAGE_SIZE);
|
|
||||||
|
|
||||||
/* make sure there are enough buffer pages and init request with them */
|
|
||||||
err = -ENOMEM;
|
|
||||||
if (max_pages > fm->fc->max_pages)
|
|
||||||
goto out;
|
|
||||||
while (ap.num_pages < max_pages) {
|
|
||||||
ap.pages[ap.num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
|
|
||||||
if (!ap.pages[ap.num_pages])
|
|
||||||
goto out;
|
|
||||||
ap.num_pages++;
|
|
||||||
}
|
|
||||||
|
|
||||||
|
|
||||||
/* okay, let's send it to the client */
|
|
||||||
ap.args.opcode = FUSE_IOCTL;
|
|
||||||
ap.args.nodeid = ff->nodeid;
|
|
||||||
ap.args.in_numargs = 1;
|
|
||||||
ap.args.in_args[0].size = sizeof(inarg);
|
|
||||||
ap.args.in_args[0].value = &inarg;
|
|
||||||
if (in_size) {
|
|
||||||
ap.args.in_numargs++;
|
|
||||||
ap.args.in_args[1].size = in_size;
|
|
||||||
ap.args.in_pages = true;
|
|
||||||
|
|
||||||
err = -EFAULT;
|
|
||||||
iov_iter_init(&ii, WRITE, in_iov, in_iovs, in_size);
|
|
||||||
for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= ap.num_pages); i++) {
|
|
||||||
c = copy_page_from_iter(ap.pages[i], 0, PAGE_SIZE, &ii);
|
|
||||||
if (c != PAGE_SIZE && iov_iter_count(&ii))
|
|
||||||
goto out;
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
ap.args.out_numargs = 2;
|
|
||||||
ap.args.out_args[0].size = sizeof(outarg);
|
|
||||||
ap.args.out_args[0].value = &outarg;
|
|
||||||
ap.args.out_args[1].size = out_size;
|
|
||||||
ap.args.out_pages = true;
|
|
||||||
ap.args.out_argvar = true;
|
|
||||||
|
|
||||||
transferred = fuse_simple_request(fm, &ap.args);
|
|
||||||
err = transferred;
|
|
||||||
if (transferred < 0)
|
|
||||||
goto out;
|
|
||||||
|
|
||||||
/* did it ask for retry? */
|
|
||||||
if (outarg.flags & FUSE_IOCTL_RETRY) {
|
|
||||||
void *vaddr;
|
|
||||||
|
|
||||||
/* no retry if in restricted mode */
|
|
||||||
err = -EIO;
|
|
||||||
if (!(flags & FUSE_IOCTL_UNRESTRICTED))
|
|
||||||
goto out;
|
|
||||||
|
|
||||||
in_iovs = outarg.in_iovs;
|
|
||||||
out_iovs = outarg.out_iovs;
|
|
||||||
|
|
||||||
/*
|
|
||||||
* Make sure things are in boundary, separate checks
|
|
||||||
* are to protect against overflow.
|
|
||||||
*/
|
|
||||||
err = -ENOMEM;
|
|
||||||
if (in_iovs > FUSE_IOCTL_MAX_IOV ||
|
|
||||||
out_iovs > FUSE_IOCTL_MAX_IOV ||
|
|
||||||
in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV)
|
|
||||||
goto out;
|
|
||||||
|
|
||||||
vaddr = kmap_atomic(ap.pages[0]);
|
|
||||||
err = fuse_copy_ioctl_iovec(fm->fc, iov_page, vaddr,
|
|
||||||
transferred, in_iovs + out_iovs,
|
|
||||||
(flags & FUSE_IOCTL_COMPAT) != 0);
|
|
||||||
kunmap_atomic(vaddr);
|
|
||||||
if (err)
|
|
||||||
goto out;
|
|
||||||
|
|
||||||
in_iov = iov_page;
|
|
||||||
out_iov = in_iov + in_iovs;
|
|
||||||
|
|
||||||
err = fuse_verify_ioctl_iov(fm->fc, in_iov, in_iovs);
|
|
||||||
if (err)
|
|
||||||
goto out;
|
|
||||||
|
|
||||||
err = fuse_verify_ioctl_iov(fm->fc, out_iov, out_iovs);
|
|
||||||
if (err)
|
|
||||||
goto out;
|
|
||||||
|
|
||||||
goto retry;
|
|
||||||
}
|
|
||||||
|
|
||||||
err = -EIO;
|
|
||||||
if (transferred > inarg.out_size)
|
|
||||||
goto out;
|
|
||||||
|
|
||||||
err = -EFAULT;
|
|
||||||
iov_iter_init(&ii, READ, out_iov, out_iovs, transferred);
|
|
||||||
for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= ap.num_pages); i++) {
|
|
||||||
c = copy_page_to_iter(ap.pages[i], 0, PAGE_SIZE, &ii);
|
|
||||||
if (c != PAGE_SIZE && iov_iter_count(&ii))
|
|
||||||
goto out;
|
|
||||||
}
|
|
||||||
err = 0;
|
|
||||||
out:
|
|
||||||
free_page((unsigned long) iov_page);
|
|
||||||
while (ap.num_pages)
|
|
||||||
__free_page(ap.pages[--ap.num_pages]);
|
|
||||||
kfree(ap.pages);
|
|
||||||
|
|
||||||
return err ? err : outarg.result;
|
|
||||||
}
|
|
||||||
EXPORT_SYMBOL_GPL(fuse_do_ioctl);
|
|
||||||
|
|
||||||
long fuse_ioctl_common(struct file *file, unsigned int cmd,
|
|
||||||
unsigned long arg, unsigned int flags)
|
|
||||||
{
|
|
||||||
struct inode *inode = file_inode(file);
|
|
||||||
struct fuse_conn *fc = get_fuse_conn(inode);
|
|
||||||
|
|
||||||
if (!fuse_allow_current_process(fc))
|
|
||||||
return -EACCES;
|
|
||||||
|
|
||||||
if (fuse_is_bad(inode))
|
|
||||||
return -EIO;
|
|
||||||
|
|
||||||
return fuse_do_ioctl(file, cmd, arg, flags);
|
|
||||||
}
|
|
||||||
|
|
||||||
static long fuse_file_ioctl(struct file *file, unsigned int cmd,
|
|
||||||
unsigned long arg)
|
|
||||||
{
|
|
||||||
return fuse_ioctl_common(file, cmd, arg, 0);
|
|
||||||
}
|
|
||||||
|
|
||||||
static long fuse_file_compat_ioctl(struct file *file, unsigned int cmd,
|
|
||||||
unsigned long arg)
|
|
||||||
{
|
|
||||||
return fuse_ioctl_common(file, cmd, arg, FUSE_IOCTL_COMPAT);
|
|
||||||
}
|
|
||||||
|
|
||||||
/*
|
/*
|
||||||
* All files which have been polled are linked to RB tree
|
* All files which have been polled are linked to RB tree
|
||||||
* fuse_conn->polled_files which is indexed by kh. Walk the tree and
|
* fuse_conn->polled_files which is indexed by kh. Walk the tree and
|
||||||
|
|||||||
@@ -872,6 +872,28 @@ static inline bool fuse_is_bad(struct inode *inode)
|
|||||||
return unlikely(test_bit(FUSE_I_BAD, &get_fuse_inode(inode)->state));
|
return unlikely(test_bit(FUSE_I_BAD, &get_fuse_inode(inode)->state));
|
||||||
}
|
}
|
||||||
|
|
||||||
|
static inline struct page **fuse_pages_alloc(unsigned int npages, gfp_t flags,
|
||||||
|
struct fuse_page_desc **desc)
|
||||||
|
{
|
||||||
|
struct page **pages;
|
||||||
|
|
||||||
|
pages = kzalloc(npages * (sizeof(struct page *) +
|
||||||
|
sizeof(struct fuse_page_desc)), flags);
|
||||||
|
*desc = (void *) (pages + npages);
|
||||||
|
|
||||||
|
return pages;
|
||||||
|
}
|
||||||
|
|
||||||
|
static inline void fuse_page_descs_length_init(struct fuse_page_desc *descs,
|
||||||
|
unsigned int index,
|
||||||
|
unsigned int nr_pages)
|
||||||
|
{
|
||||||
|
int i;
|
||||||
|
|
||||||
|
for (i = index; i < index + nr_pages; i++)
|
||||||
|
descs[i].length = PAGE_SIZE - descs[i].offset;
|
||||||
|
}
|
||||||
|
|
||||||
/** Device operations */
|
/** Device operations */
|
||||||
extern const struct file_operations fuse_dev_operations;
|
extern const struct file_operations fuse_dev_operations;
|
||||||
|
|
||||||
@@ -1214,4 +1236,9 @@ void fuse_dax_inode_cleanup(struct inode *inode);
|
|||||||
bool fuse_dax_check_alignment(struct fuse_conn *fc, unsigned int map_alignment);
|
bool fuse_dax_check_alignment(struct fuse_conn *fc, unsigned int map_alignment);
|
||||||
void fuse_dax_cancel_work(struct fuse_conn *fc);
|
void fuse_dax_cancel_work(struct fuse_conn *fc);
|
||||||
|
|
||||||
|
/* ioctl.c */
|
||||||
|
long fuse_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
|
||||||
|
long fuse_file_compat_ioctl(struct file *file, unsigned int cmd,
|
||||||
|
unsigned long arg);
|
||||||
|
|
||||||
#endif /* _FS_FUSE_I_H */
|
#endif /* _FS_FUSE_I_H */
|
||||||
|
|||||||
366
fs/fuse/ioctl.c
Normal file
366
fs/fuse/ioctl.c
Normal file
@@ -0,0 +1,366 @@
|
|||||||
|
// SPDX-License-Identifier: GPL-2.0-only
|
||||||
|
/*
|
||||||
|
* Copyright (C) 2017 Red Hat, Inc.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#include "fuse_i.h"
|
||||||
|
|
||||||
|
#include <linux/uio.h>
|
||||||
|
#include <linux/compat.h>
|
||||||
|
#include <linux/fileattr.h>
|
||||||
|
|
||||||
|
/*
|
||||||
|
* CUSE servers compiled on 32bit broke on 64bit kernels because the
|
||||||
|
* ABI was defined to be 'struct iovec' which is different on 32bit
|
||||||
|
* and 64bit. Fortunately we can determine which structure the server
|
||||||
|
* used from the size of the reply.
|
||||||
|
*/
|
||||||
|
static int fuse_copy_ioctl_iovec_old(struct iovec *dst, void *src,
|
||||||
|
size_t transferred, unsigned count,
|
||||||
|
bool is_compat)
|
||||||
|
{
|
||||||
|
#ifdef CONFIG_COMPAT
|
||||||
|
if (count * sizeof(struct compat_iovec) == transferred) {
|
||||||
|
struct compat_iovec *ciov = src;
|
||||||
|
unsigned i;
|
||||||
|
|
||||||
|
/*
|
||||||
|
* With this interface a 32bit server cannot support
|
||||||
|
* non-compat (i.e. ones coming from 64bit apps) ioctl
|
||||||
|
* requests
|
||||||
|
*/
|
||||||
|
if (!is_compat)
|
||||||
|
return -EINVAL;
|
||||||
|
|
||||||
|
for (i = 0; i < count; i++) {
|
||||||
|
dst[i].iov_base = compat_ptr(ciov[i].iov_base);
|
||||||
|
dst[i].iov_len = ciov[i].iov_len;
|
||||||
|
}
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
#endif
|
||||||
|
|
||||||
|
if (count * sizeof(struct iovec) != transferred)
|
||||||
|
return -EIO;
|
||||||
|
|
||||||
|
memcpy(dst, src, transferred);
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Make sure iov_length() won't overflow */
|
||||||
|
static int fuse_verify_ioctl_iov(struct fuse_conn *fc, struct iovec *iov,
|
||||||
|
size_t count)
|
||||||
|
{
|
||||||
|
size_t n;
|
||||||
|
u32 max = fc->max_pages << PAGE_SHIFT;
|
||||||
|
|
||||||
|
for (n = 0; n < count; n++, iov++) {
|
||||||
|
if (iov->iov_len > (size_t) max)
|
||||||
|
return -ENOMEM;
|
||||||
|
max -= iov->iov_len;
|
||||||
|
}
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
static int fuse_copy_ioctl_iovec(struct fuse_conn *fc, struct iovec *dst,
|
||||||
|
void *src, size_t transferred, unsigned count,
|
||||||
|
bool is_compat)
|
||||||
|
{
|
||||||
|
unsigned i;
|
||||||
|
struct fuse_ioctl_iovec *fiov = src;
|
||||||
|
|
||||||
|
if (fc->minor < 16) {
|
||||||
|
return fuse_copy_ioctl_iovec_old(dst, src, transferred,
|
||||||
|
count, is_compat);
|
||||||
|
}
|
||||||
|
|
||||||
|
if (count * sizeof(struct fuse_ioctl_iovec) != transferred)
|
||||||
|
return -EIO;
|
||||||
|
|
||||||
|
for (i = 0; i < count; i++) {
|
||||||
|
/* Did the server supply an inappropriate value? */
|
||||||
|
if (fiov[i].base != (unsigned long) fiov[i].base ||
|
||||||
|
fiov[i].len != (unsigned long) fiov[i].len)
|
||||||
|
return -EIO;
|
||||||
|
|
||||||
|
dst[i].iov_base = (void __user *) (unsigned long) fiov[i].base;
|
||||||
|
dst[i].iov_len = (size_t) fiov[i].len;
|
||||||
|
|
||||||
|
#ifdef CONFIG_COMPAT
|
||||||
|
if (is_compat &&
|
||||||
|
(ptr_to_compat(dst[i].iov_base) != fiov[i].base ||
|
||||||
|
(compat_size_t) dst[i].iov_len != fiov[i].len))
|
||||||
|
return -EIO;
|
||||||
|
#endif
|
||||||
|
}
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
/*
|
||||||
|
* For ioctls, there is no generic way to determine how much memory
|
||||||
|
* needs to be read and/or written. Furthermore, ioctls are allowed
|
||||||
|
* to dereference the passed pointer, so the parameter requires deep
|
||||||
|
* copying but FUSE has no idea whatsoever about what to copy in or
|
||||||
|
* out.
|
||||||
|
*
|
||||||
|
* This is solved by allowing FUSE server to retry ioctl with
|
||||||
|
* necessary in/out iovecs. Let's assume the ioctl implementation
|
||||||
|
* needs to read in the following structure.
|
||||||
|
*
|
||||||
|
* struct a {
|
||||||
|
* char *buf;
|
||||||
|
* size_t buflen;
|
||||||
|
* }
|
||||||
|
*
|
||||||
|
* On the first callout to FUSE server, inarg->in_size and
|
||||||
|
* inarg->out_size will be NULL; then, the server completes the ioctl
|
||||||
|
* with FUSE_IOCTL_RETRY set in out->flags, out->in_iovs set to 1 and
|
||||||
|
* the actual iov array to
|
||||||
|
*
|
||||||
|
* { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) } }
|
||||||
|
*
|
||||||
|
* which tells FUSE to copy in the requested area and retry the ioctl.
|
||||||
|
* On the second round, the server has access to the structure and
|
||||||
|
* from that it can tell what to look for next, so on the invocation,
|
||||||
|
* it sets FUSE_IOCTL_RETRY, out->in_iovs to 2 and iov array to
|
||||||
|
*
|
||||||
|
* { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) },
|
||||||
|
* { .iov_base = a.buf, .iov_len = a.buflen } }
|
||||||
|
*
|
||||||
|
* FUSE will copy both struct a and the pointed buffer from the
|
||||||
|
* process doing the ioctl and retry ioctl with both struct a and the
|
||||||
|
* buffer.
|
||||||
|
*
|
||||||
|
* This time, FUSE server has everything it needs and completes ioctl
|
||||||
|
* without FUSE_IOCTL_RETRY which finishes the ioctl call.
|
||||||
|
*
|
||||||
|
* Copying data out works the same way.
|
||||||
|
*
|
||||||
|
* Note that if FUSE_IOCTL_UNRESTRICTED is clear, the kernel
|
||||||
|
* automatically initializes in and out iovs by decoding @cmd with
|
||||||
|
* _IOC_* macros and the server is not allowed to request RETRY. This
|
||||||
|
* limits ioctl data transfers to well-formed ioctls and is the forced
|
||||||
|
* behavior for all FUSE servers.
|
||||||
|
*/
|
||||||
|
long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
|
||||||
|
unsigned int flags)
|
||||||
|
{
|
||||||
|
struct fuse_file *ff = file->private_data;
|
||||||
|
struct fuse_mount *fm = ff->fm;
|
||||||
|
struct fuse_ioctl_in inarg = {
|
||||||
|
.fh = ff->fh,
|
||||||
|
.cmd = cmd,
|
||||||
|
.arg = arg,
|
||||||
|
.flags = flags
|
||||||
|
};
|
||||||
|
struct fuse_ioctl_out outarg;
|
||||||
|
struct iovec *iov_page = NULL;
|
||||||
|
struct iovec *in_iov = NULL, *out_iov = NULL;
|
||||||
|
unsigned int in_iovs = 0, out_iovs = 0, max_pages;
|
||||||
|
size_t in_size, out_size, c;
|
||||||
|
ssize_t transferred;
|
||||||
|
int err, i;
|
||||||
|
struct iov_iter ii;
|
||||||
|
struct fuse_args_pages ap = {};
|
||||||
|
|
||||||
|
#if BITS_PER_LONG == 32
|
||||||
|
inarg.flags |= FUSE_IOCTL_32BIT;
|
||||||
|
#else
|
||||||
|
if (flags & FUSE_IOCTL_COMPAT) {
|
||||||
|
inarg.flags |= FUSE_IOCTL_32BIT;
|
||||||
|
#ifdef CONFIG_X86_X32
|
||||||
|
if (in_x32_syscall())
|
||||||
|
inarg.flags |= FUSE_IOCTL_COMPAT_X32;
|
||||||
|
#endif
|
||||||
|
}
|
||||||
|
#endif
|
||||||
|
|
||||||
|
/* assume all the iovs returned by client always fits in a page */
|
||||||
|
BUILD_BUG_ON(sizeof(struct fuse_ioctl_iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE);
|
||||||
|
|
||||||
|
err = -ENOMEM;
|
||||||
|
ap.pages = fuse_pages_alloc(fm->fc->max_pages, GFP_KERNEL, &ap.descs);
|
||||||
|
iov_page = (struct iovec *) __get_free_page(GFP_KERNEL);
|
||||||
|
if (!ap.pages || !iov_page)
|
||||||
|
goto out;
|
||||||
|
|
||||||
|
fuse_page_descs_length_init(ap.descs, 0, fm->fc->max_pages);
|
||||||
|
|
||||||
|
/*
|
||||||
|
* If restricted, initialize IO parameters as encoded in @cmd.
|
||||||
|
* RETRY from server is not allowed.
|
||||||
|
*/
|
||||||
|
if (!(flags & FUSE_IOCTL_UNRESTRICTED)) {
|
||||||
|
struct iovec *iov = iov_page;
|
||||||
|
|
||||||
|
iov->iov_base = (void __user *)arg;
|
||||||
|
|
||||||
|
switch (cmd) {
|
||||||
|
case FS_IOC_GETFLAGS:
|
||||||
|
case FS_IOC_SETFLAGS:
|
||||||
|
iov->iov_len = sizeof(int);
|
||||||
|
break;
|
||||||
|
default:
|
||||||
|
iov->iov_len = _IOC_SIZE(cmd);
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
|
||||||
|
if (_IOC_DIR(cmd) & _IOC_WRITE) {
|
||||||
|
in_iov = iov;
|
||||||
|
in_iovs = 1;
|
||||||
|
}
|
||||||
|
|
||||||
|
if (_IOC_DIR(cmd) & _IOC_READ) {
|
||||||
|
out_iov = iov;
|
||||||
|
out_iovs = 1;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
retry:
|
||||||
|
inarg.in_size = in_size = iov_length(in_iov, in_iovs);
|
||||||
|
inarg.out_size = out_size = iov_length(out_iov, out_iovs);
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Out data can be used either for actual out data or iovs,
|
||||||
|
* make sure there always is at least one page.
|
||||||
|
*/
|
||||||
|
out_size = max_t(size_t, out_size, PAGE_SIZE);
|
||||||
|
max_pages = DIV_ROUND_UP(max(in_size, out_size), PAGE_SIZE);
|
||||||
|
|
||||||
|
/* make sure there are enough buffer pages and init request with them */
|
||||||
|
err = -ENOMEM;
|
||||||
|
if (max_pages > fm->fc->max_pages)
|
||||||
|
goto out;
|
||||||
|
while (ap.num_pages < max_pages) {
|
||||||
|
ap.pages[ap.num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
|
||||||
|
if (!ap.pages[ap.num_pages])
|
||||||
|
goto out;
|
||||||
|
ap.num_pages++;
|
||||||
|
}
|
||||||
|
|
||||||
|
|
||||||
|
/* okay, let's send it to the client */
|
||||||
|
ap.args.opcode = FUSE_IOCTL;
|
||||||
|
ap.args.nodeid = ff->nodeid;
|
||||||
|
ap.args.in_numargs = 1;
|
||||||
|
ap.args.in_args[0].size = sizeof(inarg);
|
||||||
|
ap.args.in_args[0].value = &inarg;
|
||||||
|
if (in_size) {
|
||||||
|
ap.args.in_numargs++;
|
||||||
|
ap.args.in_args[1].size = in_size;
|
||||||
|
ap.args.in_pages = true;
|
||||||
|
|
||||||
|
err = -EFAULT;
|
||||||
|
iov_iter_init(&ii, WRITE, in_iov, in_iovs, in_size);
|
||||||
|
for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= ap.num_pages); i++) {
|
||||||
|
c = copy_page_from_iter(ap.pages[i], 0, PAGE_SIZE, &ii);
|
||||||
|
if (c != PAGE_SIZE && iov_iter_count(&ii))
|
||||||
|
goto out;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
ap.args.out_numargs = 2;
|
||||||
|
ap.args.out_args[0].size = sizeof(outarg);
|
||||||
|
ap.args.out_args[0].value = &outarg;
|
||||||
|
ap.args.out_args[1].size = out_size;
|
||||||
|
ap.args.out_pages = true;
|
||||||
|
ap.args.out_argvar = true;
|
||||||
|
|
||||||
|
transferred = fuse_simple_request(fm, &ap.args);
|
||||||
|
err = transferred;
|
||||||
|
if (transferred < 0)
|
||||||
|
goto out;
|
||||||
|
|
||||||
|
/* did it ask for retry? */
|
||||||
|
if (outarg.flags & FUSE_IOCTL_RETRY) {
|
||||||
|
void *vaddr;
|
||||||
|
|
||||||
|
/* no retry if in restricted mode */
|
||||||
|
err = -EIO;
|
||||||
|
if (!(flags & FUSE_IOCTL_UNRESTRICTED))
|
||||||
|
goto out;
|
||||||
|
|
||||||
|
in_iovs = outarg.in_iovs;
|
||||||
|
out_iovs = outarg.out_iovs;
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Make sure things are in boundary, separate checks
|
||||||
|
* are to protect against overflow.
|
||||||
|
*/
|
||||||
|
err = -ENOMEM;
|
||||||
|
if (in_iovs > FUSE_IOCTL_MAX_IOV ||
|
||||||
|
out_iovs > FUSE_IOCTL_MAX_IOV ||
|
||||||
|
in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV)
|
||||||
|
goto out;
|
||||||
|
|
||||||
|
vaddr = kmap_atomic(ap.pages[0]);
|
||||||
|
err = fuse_copy_ioctl_iovec(fm->fc, iov_page, vaddr,
|
||||||
|
transferred, in_iovs + out_iovs,
|
||||||
|
(flags & FUSE_IOCTL_COMPAT) != 0);
|
||||||
|
kunmap_atomic(vaddr);
|
||||||
|
if (err)
|
||||||
|
goto out;
|
||||||
|
|
||||||
|
in_iov = iov_page;
|
||||||
|
out_iov = in_iov + in_iovs;
|
||||||
|
|
||||||
|
err = fuse_verify_ioctl_iov(fm->fc, in_iov, in_iovs);
|
||||||
|
if (err)
|
||||||
|
goto out;
|
||||||
|
|
||||||
|
err = fuse_verify_ioctl_iov(fm->fc, out_iov, out_iovs);
|
||||||
|
if (err)
|
||||||
|
goto out;
|
||||||
|
|
||||||
|
goto retry;
|
||||||
|
}
|
||||||
|
|
||||||
|
err = -EIO;
|
||||||
|
if (transferred > inarg.out_size)
|
||||||
|
goto out;
|
||||||
|
|
||||||
|
err = -EFAULT;
|
||||||
|
iov_iter_init(&ii, READ, out_iov, out_iovs, transferred);
|
||||||
|
for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= ap.num_pages); i++) {
|
||||||
|
c = copy_page_to_iter(ap.pages[i], 0, PAGE_SIZE, &ii);
|
||||||
|
if (c != PAGE_SIZE && iov_iter_count(&ii))
|
||||||
|
goto out;
|
||||||
|
}
|
||||||
|
err = 0;
|
||||||
|
out:
|
||||||
|
free_page((unsigned long) iov_page);
|
||||||
|
while (ap.num_pages)
|
||||||
|
__free_page(ap.pages[--ap.num_pages]);
|
||||||
|
kfree(ap.pages);
|
||||||
|
|
||||||
|
return err ? err : outarg.result;
|
||||||
|
}
|
||||||
|
EXPORT_SYMBOL_GPL(fuse_do_ioctl);
|
||||||
|
|
||||||
|
long fuse_ioctl_common(struct file *file, unsigned int cmd,
|
||||||
|
unsigned long arg, unsigned int flags)
|
||||||
|
{
|
||||||
|
struct inode *inode = file_inode(file);
|
||||||
|
struct fuse_conn *fc = get_fuse_conn(inode);
|
||||||
|
|
||||||
|
if (!fuse_allow_current_process(fc))
|
||||||
|
return -EACCES;
|
||||||
|
|
||||||
|
if (fuse_is_bad(inode))
|
||||||
|
return -EIO;
|
||||||
|
|
||||||
|
return fuse_do_ioctl(file, cmd, arg, flags);
|
||||||
|
}
|
||||||
|
|
||||||
|
long fuse_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
|
||||||
|
{
|
||||||
|
return fuse_ioctl_common(file, cmd, arg, 0);
|
||||||
|
}
|
||||||
|
|
||||||
|
long fuse_file_compat_ioctl(struct file *file, unsigned int cmd,
|
||||||
|
unsigned long arg)
|
||||||
|
{
|
||||||
|
return fuse_ioctl_common(file, cmd, arg, FUSE_IOCTL_COMPAT);
|
||||||
|
}
|
||||||
Reference in New Issue
Block a user