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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
parent
51db776a43
commit
9ac29fd3f8
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@ -7,7 +7,7 @@ obj-$(CONFIG_FUSE_FS) += fuse.o
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obj-$(CONFIG_CUSE) += cuse.o
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obj-$(CONFIG_VIRTIO_FS) += virtiofs.o
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fuse-y := dev.o dir.o file.o inode.o control.o xattr.o acl.o readdir.o
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fuse-y := dev.o dir.o file.o inode.o control.o xattr.o acl.o readdir.o ioctl.o
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fuse-$(CONFIG_FUSE_DAX) += dax.o
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virtiofs-y := virtio_fs.o
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380
fs/fuse/file.c
380
fs/fuse/file.c
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@ -14,24 +14,11 @@
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#include <linux/sched.h>
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#include <linux/sched/signal.h>
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#include <linux/module.h>
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#include <linux/compat.h>
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#include <linux/swap.h>
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#include <linux/falloc.h>
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#include <linux/uio.h>
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#include <linux/fs.h>
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static struct page **fuse_pages_alloc(unsigned int npages, gfp_t flags,
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struct fuse_page_desc **desc)
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{
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struct page **pages;
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pages = kzalloc(npages * (sizeof(struct page *) +
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sizeof(struct fuse_page_desc)), flags);
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*desc = (void *) (pages + npages);
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return pages;
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}
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static int fuse_send_open(struct fuse_mount *fm, u64 nodeid, struct file *file,
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int opcode, struct fuse_open_out *outargp)
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{
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@ -1346,16 +1333,6 @@ out:
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return written ? written : err;
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}
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static inline void fuse_page_descs_length_init(struct fuse_page_desc *descs,
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unsigned int index,
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unsigned int nr_pages)
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{
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int i;
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for (i = index; i < index + nr_pages; i++)
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descs[i].length = PAGE_SIZE - descs[i].offset;
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}
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static inline unsigned long fuse_get_user_addr(const struct iov_iter *ii)
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{
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return (unsigned long)ii->iov->iov_base + ii->iov_offset;
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@ -2636,363 +2613,6 @@ static loff_t fuse_file_llseek(struct file *file, loff_t offset, int whence)
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return retval;
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}
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/*
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* CUSE servers compiled on 32bit broke on 64bit kernels because the
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* ABI was defined to be 'struct iovec' which is different on 32bit
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* and 64bit. Fortunately we can determine which structure the server
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* used from the size of the reply.
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*/
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static int fuse_copy_ioctl_iovec_old(struct iovec *dst, void *src,
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size_t transferred, unsigned count,
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bool is_compat)
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{
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#ifdef CONFIG_COMPAT
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if (count * sizeof(struct compat_iovec) == transferred) {
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struct compat_iovec *ciov = src;
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unsigned i;
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/*
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* With this interface a 32bit server cannot support
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* non-compat (i.e. ones coming from 64bit apps) ioctl
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* requests
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*/
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if (!is_compat)
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return -EINVAL;
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for (i = 0; i < count; i++) {
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dst[i].iov_base = compat_ptr(ciov[i].iov_base);
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dst[i].iov_len = ciov[i].iov_len;
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}
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return 0;
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}
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#endif
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if (count * sizeof(struct iovec) != transferred)
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return -EIO;
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memcpy(dst, src, transferred);
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return 0;
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}
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/* Make sure iov_length() won't overflow */
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static int fuse_verify_ioctl_iov(struct fuse_conn *fc, struct iovec *iov,
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size_t count)
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{
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size_t n;
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u32 max = fc->max_pages << PAGE_SHIFT;
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for (n = 0; n < count; n++, iov++) {
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if (iov->iov_len > (size_t) max)
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return -ENOMEM;
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max -= iov->iov_len;
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}
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return 0;
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}
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static int fuse_copy_ioctl_iovec(struct fuse_conn *fc, struct iovec *dst,
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void *src, size_t transferred, unsigned count,
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bool is_compat)
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{
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unsigned i;
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struct fuse_ioctl_iovec *fiov = src;
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if (fc->minor < 16) {
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return fuse_copy_ioctl_iovec_old(dst, src, transferred,
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count, is_compat);
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}
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if (count * sizeof(struct fuse_ioctl_iovec) != transferred)
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return -EIO;
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for (i = 0; i < count; i++) {
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/* Did the server supply an inappropriate value? */
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if (fiov[i].base != (unsigned long) fiov[i].base ||
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fiov[i].len != (unsigned long) fiov[i].len)
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return -EIO;
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dst[i].iov_base = (void __user *) (unsigned long) fiov[i].base;
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dst[i].iov_len = (size_t) fiov[i].len;
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#ifdef CONFIG_COMPAT
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if (is_compat &&
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(ptr_to_compat(dst[i].iov_base) != fiov[i].base ||
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(compat_size_t) dst[i].iov_len != fiov[i].len))
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return -EIO;
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#endif
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}
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return 0;
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}
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/*
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* For ioctls, there is no generic way to determine how much memory
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* needs to be read and/or written. Furthermore, ioctls are allowed
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* to dereference the passed pointer, so the parameter requires deep
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* copying but FUSE has no idea whatsoever about what to copy in or
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* out.
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*
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* This is solved by allowing FUSE server to retry ioctl with
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* necessary in/out iovecs. Let's assume the ioctl implementation
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* needs to read in the following structure.
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*
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* struct a {
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* char *buf;
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* size_t buflen;
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* }
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*
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* On the first callout to FUSE server, inarg->in_size and
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* inarg->out_size will be NULL; then, the server completes the ioctl
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* with FUSE_IOCTL_RETRY set in out->flags, out->in_iovs set to 1 and
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* the actual iov array to
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*
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* { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) } }
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*
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* which tells FUSE to copy in the requested area and retry the ioctl.
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* On the second round, the server has access to the structure and
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* from that it can tell what to look for next, so on the invocation,
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* it sets FUSE_IOCTL_RETRY, out->in_iovs to 2 and iov array to
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*
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* { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) },
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* { .iov_base = a.buf, .iov_len = a.buflen } }
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*
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* FUSE will copy both struct a and the pointed buffer from the
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* process doing the ioctl and retry ioctl with both struct a and the
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* buffer.
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*
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* This time, FUSE server has everything it needs and completes ioctl
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* without FUSE_IOCTL_RETRY which finishes the ioctl call.
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*
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* Copying data out works the same way.
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*
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* Note that if FUSE_IOCTL_UNRESTRICTED is clear, the kernel
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* automatically initializes in and out iovs by decoding @cmd with
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* _IOC_* macros and the server is not allowed to request RETRY. This
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* limits ioctl data transfers to well-formed ioctls and is the forced
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* behavior for all FUSE servers.
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*/
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long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg,
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unsigned int flags)
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{
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struct fuse_file *ff = file->private_data;
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struct fuse_mount *fm = ff->fm;
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struct fuse_ioctl_in inarg = {
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.fh = ff->fh,
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.cmd = cmd,
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.arg = arg,
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.flags = flags
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};
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struct fuse_ioctl_out outarg;
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struct iovec *iov_page = NULL;
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struct iovec *in_iov = NULL, *out_iov = NULL;
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unsigned int in_iovs = 0, out_iovs = 0, max_pages;
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size_t in_size, out_size, c;
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ssize_t transferred;
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int err, i;
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struct iov_iter ii;
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struct fuse_args_pages ap = {};
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#if BITS_PER_LONG == 32
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inarg.flags |= FUSE_IOCTL_32BIT;
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#else
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if (flags & FUSE_IOCTL_COMPAT) {
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inarg.flags |= FUSE_IOCTL_32BIT;
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#ifdef CONFIG_X86_X32
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if (in_x32_syscall())
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inarg.flags |= FUSE_IOCTL_COMPAT_X32;
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#endif
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}
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#endif
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/* assume all the iovs returned by client always fits in a page */
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BUILD_BUG_ON(sizeof(struct fuse_ioctl_iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE);
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err = -ENOMEM;
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ap.pages = fuse_pages_alloc(fm->fc->max_pages, GFP_KERNEL, &ap.descs);
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iov_page = (struct iovec *) __get_free_page(GFP_KERNEL);
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if (!ap.pages || !iov_page)
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goto out;
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fuse_page_descs_length_init(ap.descs, 0, fm->fc->max_pages);
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/*
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* If restricted, initialize IO parameters as encoded in @cmd.
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* RETRY from server is not allowed.
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*/
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if (!(flags & FUSE_IOCTL_UNRESTRICTED)) {
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struct iovec *iov = iov_page;
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iov->iov_base = (void __user *)arg;
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switch (cmd) {
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case FS_IOC_GETFLAGS:
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case FS_IOC_SETFLAGS:
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iov->iov_len = sizeof(int);
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break;
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default:
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iov->iov_len = _IOC_SIZE(cmd);
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break;
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}
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if (_IOC_DIR(cmd) & _IOC_WRITE) {
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in_iov = iov;
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in_iovs = 1;
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}
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if (_IOC_DIR(cmd) & _IOC_READ) {
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out_iov = iov;
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out_iovs = 1;
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}
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}
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retry:
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inarg.in_size = in_size = iov_length(in_iov, in_iovs);
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inarg.out_size = out_size = iov_length(out_iov, out_iovs);
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/*
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* Out data can be used either for actual out data or iovs,
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* make sure there always is at least one page.
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*/
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out_size = max_t(size_t, out_size, PAGE_SIZE);
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max_pages = DIV_ROUND_UP(max(in_size, out_size), PAGE_SIZE);
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/* make sure there are enough buffer pages and init request with them */
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err = -ENOMEM;
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if (max_pages > fm->fc->max_pages)
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goto out;
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while (ap.num_pages < max_pages) {
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ap.pages[ap.num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
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if (!ap.pages[ap.num_pages])
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goto out;
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ap.num_pages++;
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}
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/* okay, let's send it to the client */
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ap.args.opcode = FUSE_IOCTL;
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ap.args.nodeid = ff->nodeid;
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ap.args.in_numargs = 1;
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ap.args.in_args[0].size = sizeof(inarg);
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ap.args.in_args[0].value = &inarg;
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if (in_size) {
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ap.args.in_numargs++;
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ap.args.in_args[1].size = in_size;
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ap.args.in_pages = true;
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err = -EFAULT;
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iov_iter_init(&ii, WRITE, in_iov, in_iovs, in_size);
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for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= ap.num_pages); i++) {
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c = copy_page_from_iter(ap.pages[i], 0, PAGE_SIZE, &ii);
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if (c != PAGE_SIZE && iov_iter_count(&ii))
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goto out;
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}
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}
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ap.args.out_numargs = 2;
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ap.args.out_args[0].size = sizeof(outarg);
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ap.args.out_args[0].value = &outarg;
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ap.args.out_args[1].size = out_size;
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ap.args.out_pages = true;
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ap.args.out_argvar = true;
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transferred = fuse_simple_request(fm, &ap.args);
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err = transferred;
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if (transferred < 0)
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goto out;
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/* did it ask for retry? */
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if (outarg.flags & FUSE_IOCTL_RETRY) {
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void *vaddr;
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/* no retry if in restricted mode */
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err = -EIO;
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if (!(flags & FUSE_IOCTL_UNRESTRICTED))
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goto out;
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in_iovs = outarg.in_iovs;
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out_iovs = outarg.out_iovs;
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/*
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* Make sure things are in boundary, separate checks
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* are to protect against overflow.
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*/
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err = -ENOMEM;
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if (in_iovs > FUSE_IOCTL_MAX_IOV ||
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out_iovs > FUSE_IOCTL_MAX_IOV ||
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in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV)
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goto out;
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vaddr = kmap_atomic(ap.pages[0]);
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err = fuse_copy_ioctl_iovec(fm->fc, iov_page, vaddr,
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transferred, in_iovs + out_iovs,
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(flags & FUSE_IOCTL_COMPAT) != 0);
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kunmap_atomic(vaddr);
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if (err)
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goto out;
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in_iov = iov_page;
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out_iov = in_iov + in_iovs;
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err = fuse_verify_ioctl_iov(fm->fc, in_iov, in_iovs);
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if (err)
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goto out;
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err = fuse_verify_ioctl_iov(fm->fc, out_iov, out_iovs);
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if (err)
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goto out;
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goto retry;
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}
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err = -EIO;
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if (transferred > inarg.out_size)
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goto out;
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err = -EFAULT;
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iov_iter_init(&ii, READ, out_iov, out_iovs, transferred);
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for (i = 0; iov_iter_count(&ii) && !WARN_ON(i >= ap.num_pages); i++) {
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c = copy_page_to_iter(ap.pages[i], 0, PAGE_SIZE, &ii);
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if (c != PAGE_SIZE && iov_iter_count(&ii))
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goto out;
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}
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err = 0;
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out:
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free_page((unsigned long) iov_page);
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while (ap.num_pages)
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__free_page(ap.pages[--ap.num_pages]);
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kfree(ap.pages);
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return err ? err : outarg.result;
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}
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EXPORT_SYMBOL_GPL(fuse_do_ioctl);
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long fuse_ioctl_common(struct file *file, unsigned int cmd,
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unsigned long arg, unsigned int flags)
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{
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struct inode *inode = file_inode(file);
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struct fuse_conn *fc = get_fuse_conn(inode);
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if (!fuse_allow_current_process(fc))
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return -EACCES;
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if (fuse_is_bad(inode))
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return -EIO;
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return fuse_do_ioctl(file, cmd, arg, flags);
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}
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static long fuse_file_ioctl(struct file *file, unsigned int cmd,
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unsigned long arg)
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{
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return fuse_ioctl_common(file, cmd, arg, 0);
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}
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static long fuse_file_compat_ioctl(struct file *file, unsigned int cmd,
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unsigned long arg)
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{
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return fuse_ioctl_common(file, cmd, arg, FUSE_IOCTL_COMPAT);
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}
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/*
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* All files which have been polled are linked to RB tree
|
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* fuse_conn->polled_files which is indexed by kh. Walk the tree and
|
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|
|
|
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|
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@ -872,6 +872,28 @@ static inline bool fuse_is_bad(struct inode *inode)
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return unlikely(test_bit(FUSE_I_BAD, &get_fuse_inode(inode)->state));
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}
|
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|
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static inline struct page **fuse_pages_alloc(unsigned int npages, gfp_t flags,
|
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struct fuse_page_desc **desc)
|
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{
|
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struct page **pages;
|
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|
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pages = kzalloc(npages * (sizeof(struct page *) +
|
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sizeof(struct fuse_page_desc)), flags);
|
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*desc = (void *) (pages + npages);
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|
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return pages;
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}
|
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|
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static inline void fuse_page_descs_length_init(struct fuse_page_desc *descs,
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unsigned int index,
|
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unsigned int nr_pages)
|
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{
|
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int i;
|
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|
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for (i = index; i < index + nr_pages; i++)
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descs[i].length = PAGE_SIZE - descs[i].offset;
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}
|
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|
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/** Device operations */
|
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extern const struct file_operations fuse_dev_operations;
|
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|
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|
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@ -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);
|
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void fuse_dax_cancel_work(struct fuse_conn *fc);
|
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|
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/* ioctl.c */
|
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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 */
|
||||
|
|
|
|||
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);
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user