Unverified Commit dff745c1 authored by Amir Goldstein's avatar Amir Goldstein Committed by Christian Brauner
Browse files

fs: move cleanup from init_file() into its callers 



The use of file_free_rcu() in init_file() to free the struct that was
allocated by the caller was hacky and we got what we deserved.

Let init_file() and its callers take care of cleaning up each after
their own allocated resources on error.

Fixes: 62d53c4a ("fs: use backing_file container for internal files with "fake" f_path") # mainline only
Reported-and-tested-by: default avatar <syzbot+ada42aab05cf51b00e98@syzkaller.appspotmail.com>
Signed-off-by: default avatarAmir Goldstein <amir73il@gmail.com>
Message-Id: <20230701171134.239409-1-amir73il@gmail.com>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent 995b406c

fs/file_table.c

+10 −4
Original line number Diff line number Diff line
@@ -160,7 +160,7 @@ static int init_file(struct file *f, int flags, const struct cred *cred) 
	f->f_cred = get_cred(cred);

	error = security_file_alloc(f);

	if (unlikely(error)) {

		file_free_rcu(&f->f_rcuhead);

		put_cred(f->f_cred);

		return error;

	}
@@ -208,8 +208,10 @@ struct file *alloc_empty_file(int flags, const struct cred *cred) 
		return ERR_PTR(-ENOMEM);



	error = init_file(f, flags, cred);

	if (unlikely(error))

	if (unlikely(error)) {

		kmem_cache_free(filp_cachep, f);

		return ERR_PTR(error);

	}



	percpu_counter_inc(&nr_files);
@@ -240,8 +242,10 @@ struct file *alloc_empty_file_noaccount(int flags, const struct cred *cred) 
		return ERR_PTR(-ENOMEM);



	error = init_file(f, flags, cred);

	if (unlikely(error))

	if (unlikely(error)) {

		kmem_cache_free(filp_cachep, f);

		return ERR_PTR(error);

	}



	f->f_mode |= FMODE_NOACCOUNT;
@@ -265,8 +269,10 @@ struct file *alloc_empty_backing_file(int flags, const struct cred *cred) 
		return ERR_PTR(-ENOMEM);



	error = init_file(&ff->file, flags, cred);

	if (unlikely(error))

	if (unlikely(error)) {

		kfree(ff);

		return ERR_PTR(error);

	}



	ff->file.f_mode |= FMODE_BACKING | FMODE_NOACCOUNT;

	return &ff->file;