Commit 0fdc312f authored by Namjae Jeon's avatar Namjae Jeon Committed by openeuler-sync-bot
Browse files

ksmbd: fix slab-out-of-bounds in smb_strndup_from_utf16() 

mainline inclusion
from mainline-v6.7-rc8
commit d10c77873ba1e9e6b91905018e29e196fd5f863d
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I8YD63
CVE: CVE-2024-22705

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d10c77873ba1e9e6b91905018e29e196fd5f863d



--------------------------------

If ->NameOffset/Length is bigger than ->CreateContextsOffset/Length,
ksmbd_check_message doesn't validate request buffer it correctly.
So slab-out-of-bounds warning from calling smb_strndup_from_utf16()
in smb2_open() could happen. If ->NameLength is non-zero, Set the larger
of the two sums (Name and CreateContext size) as the offset and length of
the data area.

Reported-by: default avatarYang Chaoming <lometsj@live.com>
Cc: stable@vger.kernel.org
Signed-off-by: default avatarNamjae Jeon <linkinjeon@kernel.org>
Signed-off-by: default avatarSteve French <stfrench@microsoft.com>
Signed-off-by: default avatarZhaoLong Wang <wangzhaolong1@huawei.com>
(cherry picked from commit d6339ed9)
parent 660b0ac1

fs/ksmbd/smb2misc.c

+12 −3
Original line number Diff line number Diff line
@@ -107,16 +107,25 @@ static int smb2_get_data_area_len(unsigned int *off, unsigned int *len, 
		break;

	case SMB2_CREATE:

	{

		unsigned short int name_off =

			le16_to_cpu(((struct smb2_create_req *)hdr)->NameOffset);

		unsigned short int name_len =

			le16_to_cpu(((struct smb2_create_req *)hdr)->NameLength);



		if (((struct smb2_create_req *)hdr)->CreateContextsLength) {

			*off = le32_to_cpu(((struct smb2_create_req *)

				hdr)->CreateContextsOffset);

			*len = le32_to_cpu(((struct smb2_create_req *)

				hdr)->CreateContextsLength);

			if (!name_len)

				break;



			if (name_off + name_len < (u64)*off + *len)

				break;

		}



		*off = le16_to_cpu(((struct smb2_create_req *)hdr)->NameOffset);

		*len = le16_to_cpu(((struct smb2_create_req *)hdr)->NameLength);

		*off = name_off;

		*len = name_len;

		break;

	}

	case SMB2_QUERY_INFO: