--- fs/fuse/file.c
+++ fs/fuse/file.c
@@ -13,6 +13,7 @@
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/module.h>
+#include <linux/compat.h>
static const struct file_operations fuse_direct_io_file_operations;
@@ -85,18 +86,52 @@ struct fuse_file *fuse_file_get(struct f
return ff;
}
+static void fuse_release_async(struct work_struct *work)
+{
+ struct fuse_req *req;
+ struct fuse_conn *fc;
+ struct path path;
+
+ req = container_of(work, struct fuse_req, misc.release.work);
+ path = req->misc.release.path;
+ fc = get_fuse_conn(path.dentry->d_inode);
+
+ fuse_put_request(fc, req);
+ path_put(&path);
+}
+
static void fuse_release_end(struct fuse_conn *fc, struct fuse_req *req)
{
- path_put(&req->misc.release.path);
+ if (fc->destroy_req) {
+ /*
+ * If this is a fuseblk mount, then it's possible that
+ * releasing the path will result in releasing the
+ * super block and sending the DESTROY request. If
+ * the server is single threaded, this would hang.
+ * For this reason do the path_put() in a separate
+ * thread.
+ */
+ atomic_inc(&req->count);
+ INIT_WORK(&req->misc.release.work, fuse_release_async);
+ schedule_work(&req->misc.release.work);
+ } else {
+ path_put(&req->misc.release.path);
+ }
}
-static void fuse_file_put(struct fuse_file *ff)
+static void fuse_file_put(struct fuse_file *ff, bool sync)
{
if (atomic_dec_and_test(&ff->count)) {
struct fuse_req *req = ff->reserved_req;
- req->end = fuse_release_end;
- fuse_request_send_background(ff->fc, req);
+ if (sync) {
+ fuse_request_send(ff->fc, req);
+ path_put(&req->misc.release.path);
+ fuse_put_request(ff->fc, req);
+ } else {
+ req->end = fuse_release_end;
+ fuse_request_send_background(ff->fc, req);
+ }
kfree(ff);
}
}
@@ -134,6 +169,7 @@ EXPORT_SYMBOL_GPL(fuse_do_open);
void fuse_finish_open(struct inode *inode, struct file *file)
{
struct fuse_file *ff = file->private_data;
+ struct fuse_conn *fc = get_fuse_conn(inode);
if (ff->open_flags & FOPEN_DIRECT_IO)
file->f_op = &fuse_direct_io_file_operations;
@@ -141,6 +177,15 @@ void fuse_finish_open(struct inode *inod
invalidate_inode_pages2(inode->i_mapping);
if (ff->open_flags & FOPEN_NONSEEKABLE)
nonseekable_open(inode, file);
+ if (fc->atomic_o_trunc && (file->f_flags & O_TRUNC)) {
+ struct fuse_inode *fi = get_fuse_inode(inode);
+
+ spin_lock(&fc->lock);
+ fi->attr_version = ++fc->attr_version;
+ i_size_write(inode, 0);
+ spin_unlock(&fc->lock);
+ fuse_invalidate_attr(inode);
+ }
}
int fuse_open_common(struct inode *inode, struct file *file, bool isdir)
@@ -208,8 +253,12 @@ void fuse_release_common(struct file *fi
* Normally this will send the RELEASE request, however if
* some asynchronous READ or WRITE requests are outstanding,
* the sending will be delayed.
+ *
+ * Make the release synchronous if this is a fuseblk mount,
+ * synchronous RELEASE is allowed (and desirable) in this case
+ * because the server can be trusted not to screw up.
*/
- fuse_file_put(ff);
+ fuse_file_put(ff, ff->fc->destroy_req != NULL);
}
static int fuse_open(struct inode *inode, struct file *file)
@@ -538,7 +587,7 @@ static void fuse_readpages_end(struct fu
unlock_page(page);
}
if (req->ff)
- fuse_file_put(req->ff);
+ fuse_file_put(req->ff, false);
}
static void fuse_send_readpages(struct fuse_req *req, struct file *file)
@@ -1118,7 +1167,7 @@ static ssize_t fuse_direct_write(struct
static void fuse_writepage_free(struct fuse_conn *fc, struct fuse_req *req)
{
__free_page(req->pages[0]);
- fuse_file_put(req->ff);
+ fuse_file_put(req->ff, false);
}
static void fuse_writepage_finish(struct fuse_conn *fc, struct fuse_req *req)
@@ -1609,6 +1658,58 @@ static int fuse_ioctl_copy_user(struct p
return 0;
}
+/* Make sure iov_length() won't overflow */
+static int fuse_verify_ioctl_iov(struct iovec *iov, size_t count)
+{
+ size_t n;
+ u32 max = FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT;
+
+ for (n = 0; n < count; n++) {
+ if (iov->iov_len > (size_t) max)
+ return -ENOMEM;
+ max -= iov->iov_len;
+ }
+ return 0;
+}
+
+/*
+ * 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(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;
+}
+
/*
* For ioctls, there is no generic way to determine how much memory
* needs to be read and/or written. Furthermore, ioctls are allowed
@@ -1790,18 +1891,25 @@ long fuse_do_ioctl(struct file *file, un
in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV)
goto out;
- err = -EIO;
- if ((in_iovs + out_iovs) * sizeof(struct iovec) != transferred)
- goto out;
-
- /* okay, copy in iovs and retry */
vaddr = kmap_atomic(pages[0], KM_USER0);
- memcpy(page_address(iov_page), vaddr, transferred);
+ err = fuse_copy_ioctl_iovec(page_address(iov_page), vaddr,
+ transferred, in_iovs + out_iovs,
+ (flags & FUSE_IOCTL_COMPAT) != 0);
kunmap_atomic(vaddr, KM_USER0);
+ if (err)
+ goto out;
in_iov = page_address(iov_page);
out_iov = in_iov + in_iovs;
+ err = fuse_verify_ioctl_iov(in_iov, in_iovs);
+ if (err)
+ goto out;
+
+ err = fuse_verify_ioctl_iov(out_iov, out_iovs);
+ if (err)
+ goto out;
+
goto retry;
}
projects / ziggy471-frankenstein-kernel.git / blobdiff