1 files changed, 31 insertions, 10 deletions

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index c03034e8c152..8cccecb55fb8 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -42,6 +42,12 @@ static int fuse_send_open(struct fuse_mount *fm, u64 nodeid, struct file *file,
 	inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY);
 	if (!fm->fc->atomic_o_trunc)
 		inarg.flags &= ~O_TRUNC;
+
+	if (fm->fc->handle_killpriv_v2 &&
+	    (inarg.flags & O_TRUNC) && !capable(CAP_FSETID)) {
+		inarg.open_flags |= FUSE_OPEN_KILL_SUIDGID;
+	}
+
 	args.opcode = opcode;
 	args.nodeid = nodeid;
 	args.in_numargs = 1;
@@ -226,6 +232,9 @@ int fuse_open_common(struct inode *inode, struct file *file, bool isdir)
 	bool dax_truncate = (file->f_flags & O_TRUNC) &&
 			  fc->atomic_o_trunc && FUSE_IS_DAX(inode);
 
+	if (fuse_is_bad(inode))
+		return -EIO;
+
 	err = generic_file_open(inode, file);
 	if (err)
 		return err;
@@ -463,7 +472,7 @@ static int fuse_flush(struct file *file, fl_owner_t id)
 	FUSE_ARGS(args);
 	int err;
 
-	if (is_bad_inode(inode))
+	if (fuse_is_bad(inode))
 		return -EIO;
 
 	err = write_inode_now(inode, 1);
@@ -535,7 +544,7 @@ static int fuse_fsync(struct file *file, loff_t start, loff_t end,
 	struct fuse_conn *fc = get_fuse_conn(inode);
 	int err;
 
-	if (is_bad_inode(inode))
+	if (fuse_is_bad(inode))
 		return -EIO;
 
 	inode_lock(inode);
@@ -859,7 +868,7 @@ static int fuse_readpage(struct file *file, struct page *page)
 	int err;
 
 	err = -EIO;
-	if (is_bad_inode(inode))
+	if (fuse_is_bad(inode))
 		goto out;
 
 	err = fuse_do_readpage(file, page);
@@ -952,7 +961,7 @@ static void fuse_readahead(struct readahead_control *rac)
 	struct fuse_conn *fc = get_fuse_conn(inode);
 	unsigned int i, max_pages, nr_pages = 0;
 
-	if (is_bad_inode(inode))
+	if (fuse_is_bad(inode))
 		return;
 
 	max_pages = min_t(unsigned int, fc->max_pages,
@@ -1097,6 +1106,8 @@ static ssize_t fuse_send_write_pages(struct fuse_io_args *ia,
 
 	fuse_write_args_fill(ia, ff, pos, count);
 	ia->write.in.flags = fuse_write_flags(iocb);
+	if (fm->fc->handle_killpriv_v2 && !capable(CAP_FSETID))
+		ia->write.in.write_flags |= FUSE_WRITE_KILL_SUIDGID;
 
 	err = fuse_simple_request(fm, &ap->args);
 	if (!err && ia->write.out.size > count)
@@ -1260,17 +1271,24 @@ static ssize_t fuse_cache_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	ssize_t written_buffered = 0;
 	struct inode *inode = mapping->host;
 	ssize_t err;
+	struct fuse_conn *fc = get_fuse_conn(inode);
 	loff_t endbyte = 0;
 
-	if (get_fuse_conn(inode)->writeback_cache) {
+	if (fc->writeback_cache) {
 		/* Update size (EOF optimization) and mode (SUID clearing) */
 		err = fuse_update_attributes(mapping->host, file);
 		if (err)
 			return err;
 
+		if (fc->handle_killpriv_v2 &&
+		    should_remove_suid(file_dentry(file))) {
+			goto writethrough;
+		}
+
 		return generic_file_write_iter(iocb, from);
 	}
 
+writethrough:
 	inode_lock(inode);
 
 	/* We can write back this queue in page reclaim */
@@ -1451,7 +1469,7 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
 
 		if (write) {
 			if (!capable(CAP_FSETID))
-				ia->write.in.write_flags |= FUSE_WRITE_KILL_PRIV;
+				ia->write.in.write_flags |= FUSE_WRITE_KILL_SUIDGID;
 
 			nres = fuse_send_write(ia, pos, nbytes, owner);
 		} else {
@@ -1555,7 +1573,7 @@ static ssize_t fuse_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
 	struct fuse_file *ff = file->private_data;
 	struct inode *inode = file_inode(file);
 
-	if (is_bad_inode(inode))
+	if (fuse_is_bad(inode))
 		return -EIO;
 
 	if (FUSE_IS_DAX(inode))
@@ -1573,7 +1591,7 @@ static ssize_t fuse_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	struct fuse_file *ff = file->private_data;
 	struct inode *inode = file_inode(file);
 
-	if (is_bad_inode(inode))
+	if (fuse_is_bad(inode))
 		return -EIO;
 
 	if (FUSE_IS_DAX(inode))
@@ -2172,7 +2190,7 @@ static int fuse_writepages(struct address_space *mapping,
 	int err;
 
 	err = -EIO;
-	if (is_bad_inode(inode))
+	if (fuse_is_bad(inode))
 		goto out;
 
 	data.inode = inode;
@@ -2281,6 +2299,9 @@ static int fuse_launder_page(struct page *page)
 	int err = 0;
 	if (clear_page_dirty_for_io(page)) {
 		struct inode *inode = page->mapping->host;
+
+		/* Serialize with pending writeback for the same page */
+		fuse_wait_on_page_writeback(inode, page->index);
 		err = fuse_writepage_locked(page);
 		if (!err)
 			fuse_wait_on_page_writeback(inode, page->index);
@@ -2954,7 +2975,7 @@ long fuse_ioctl_common(struct file *file, unsigned int cmd,
 	if (!fuse_allow_current_process(fc))
 		return -EACCES;
 
-	if (is_bad_inode(inode))
+	if (fuse_is_bad(inode))
 		return -EIO;
 
 	return fuse_do_ioctl(file, cmd, arg, flags);