Commit fd6de099 authored by Yang Yingliang's avatar Yang Yingliang Committed by Namjae Jeon
Browse files

cifsd: check return value of ksmbd_vfs_getcasexattr() correctly 



If ksmbd_vfs_getcasexattr() returns -ENOMEM, stream_buf is NULL,
it will cause null-ptr-deref when using it to copy memory. So we
need check the return value of ksmbd_vfs_getcasexattr() by comparing
with 0.

Signed-off-by: default avatarYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: default avatarNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
parent 673b9ba7

fs/cifsd/vfs.c

+4 −8
Original line number Diff line number Diff line
@@ -274,7 +274,6 @@ static int ksmbd_vfs_stream_read(struct ksmbd_file *fp, char *buf, loff_t *pos, 
{

	ssize_t v_len;

	char *stream_buf = NULL;

	int err;



	ksmbd_debug(VFS, "read stream data pos : %llu, count : %zd\n",

		    *pos, count);
@@ -283,11 +282,8 @@ static int ksmbd_vfs_stream_read(struct ksmbd_file *fp, char *buf, loff_t *pos, 
				       fp->stream.name,

				       fp->stream.size,

				       &stream_buf);

	if (v_len == -ENOENT) {

		ksmbd_err("not found stream in xattr : %zd\n", v_len);

		err = -ENOENT;

		return err;

	}

	if ((int)v_len <= 0)

		return (int)v_len;



	memcpy(buf, &stream_buf[*pos], count);

	kvfree(stream_buf);
@@ -415,9 +411,9 @@ static int ksmbd_vfs_stream_write(struct ksmbd_file *fp, char *buf, loff_t *pos, 
				       fp->stream.name,

				       fp->stream.size,

				       &stream_buf);

	if (v_len == -ENOENT) {

	if ((int)v_len < 0) {

		ksmbd_err("not found stream in xattr : %zd\n", v_len);

		err = -ENOENT;

		err = (int)v_len;

		goto out;

	}